Renal anastomotic hemangioma(AH)is a rare,benign vascular tumor with unique histopathological features,a disease that is clinically rare,and existing clinical cases offer different treatment options.As reported in the...Renal anastomotic hemangioma(AH)is a rare,benign vascular tumor with unique histopathological features,a disease that is clinically rare,and existing clinical cases offer different treatment options.As reported in the text,this is a very unusual case of renal AH with AH secondary to residual renal tissue after renal clear cell carcinoma,describing a rare renal AH and a history of renal clear cell carcinoma,including ultrasound,computed tomography and magnetic re-sonance imaging.However,the available imaging data and the literature do not provide an effective basis for the diagnosis of the disease,raising the lack of un-derstanding and misdiagnosis,where the patient eventually underwent neph-rectomy,but the author is not the most appropriate surgical treatment.The po-stoperative pathological results of the patient are benign lesions,and it is unde-niable that nephrectomy is suspected to be overtreated.By reading the literature,we provide different insights into the treatment of the patient,and we hope that this paper can provide some help for the future clinical diagnosis and treatment.展开更多
BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric SMTs.CASE SUMMARY We describe ...BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric SMTs.CASE SUMMARY We describe two cases of gastric SMT-like protrusions initially misdiagnosed as gastric SMTs by the abdominal contrast-enhanced computed tomography(CT)and endoscopic ultrasound(EUS).Based on the CT and EUS findings,the patients underwent gastroscopy;however,no tumor was identified after incising the gastric wall.Subsequent surgical exploration revealed no gastric lesions in both patients,but a mass was found in the left triangular ligament of the liver.The patients underwent laparoscopic tumor resection,and the postoperative diagnosis was hepatic hemangiomas.CONCLUSION During EUS procedures,scanning across different layers and at varying degrees of gastric cavity distension,coupled with meticulous image analysis,has the potential to mitigate the likelihood of such misdiagnoses.展开更多
Accurate preoperative diagnosis is highly important for the treatment of perivascular epithelioid cell tumors(PEComas)because PEComas are mainly benign tumors and may not require surgical intervention.By analyzing the...Accurate preoperative diagnosis is highly important for the treatment of perivascular epithelioid cell tumors(PEComas)because PEComas are mainly benign tumors and may not require surgical intervention.By analyzing the causes,properties and clinical manifestations of PEComas,we summarize the challenges and solutions in the diagnosis of PEComas.展开更多
BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwa...BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwannomas of pelvic autonomic nerve plexuses,and unlike the conventional malignant peripheral nerve sheath tumor(MPNST),are not associated with neurofibromatosis.The tumor has dis-tinctive morphological,immunohistochemical and molecular features.Addi-tionally,it tends to be more aggressive and have a higher mortality.This is the first case that presents with a synchronous urothelial carcinoma of the bladder and the epithelioid variant of MPNST in the literature.It’s also the second re-ported case of EMPNST originating from the bladder wall.CASE SUMMARY In this case report,we present the detailed clinical course of a 71-year-old patient with EMPNST of the bladder alongside a literature review.CONCLUSION During the management of EMPNST cases,offering aggressive treatment moda-lities to the patient,such as radical cystectomy,is appropriate for the best chance to contain the disease,regardless of the tumor stage and the extent of local disease at initial diagnosis.展开更多
BACKGROUND Perivascular epithelioid cell tumor(PEComa)is a rare mesenchymal neoplasm that predominantly affects the kidney and uterus.The occurrence of this tumor in the liver,particularly with simultaneous involvemen...BACKGROUND Perivascular epithelioid cell tumor(PEComa)is a rare mesenchymal neoplasm that predominantly affects the kidney and uterus.The occurrence of this tumor in the liver,particularly with simultaneous involvement of the liver and kidney,is exceedingly uncommon.Pathological diagnosis is the gold standard.PEComas usually show positive immunohistochemical staining for melanocytic(HMB-45,Melan-A)and myoid(SMA,muscle-specific actin)markers.CASE SUMMARY We presented a noteworthy case of malignant PEComa affecting both the liver and kidney in a 53-year-old man with tuberous sclerosis complex(TSC).FAT2 and TP73 mutations in the kidney were identified and positive expression of diagnostic markers including HMB-45,Melan A,and TFE3 were detected.In addition,we demonstrated that hepatic artery perfusion chemotherapy was ineffective for hepatic PEComa,while surgery remained the most effective approach.Everolimus showed an excellent efficacy in the postoperative treatment of the tumor.CONCLUSION Surgical treatment is preferred for malignant PEComa affecting liver and kidney,especially with TSC;everolimus is effective postoperatively.展开更多
BACKGROUND Epithelioid trophoblastic tumor(ETT)is an extremely rare malignant gestational trophoblastic neoplasm commonly presenting with abnormal vaginal bleeding,abdominal pain,and increased human chorionic gonadotr...BACKGROUND Epithelioid trophoblastic tumor(ETT)is an extremely rare malignant gestational trophoblastic neoplasm commonly presenting with abnormal vaginal bleeding,abdominal pain,and increased human chorionic gonadotropin(hCG).This study reported a case of uterine ETT with the main manifestation being increased hCG.CASE SUMMARY A 39-year-old female was referred to the Ningbo Maternal and Child Hospital of China in December 2022,complaining of increased hCG levels for 1 month.Magnetic resonance imaging revealed gestational trophoblastic tumor,and hysteroscopic electrotomy and curettage of intrauterine hyperplasia were performed.The patient was diagnosed with uterine ETT through postoperative pathological examination and immunohistochemical results.Total laparoscopic hysterectomy and bilateral salpingectomy were performed,and hCG levels returned to normal.The patient was without recurrence during the postoperative 3-month follow-up.CONCLUSION This study reported a case of uterine ETT with the main manifestation being increased hCG,highlighting that ETT should be considered in the presence of abnormal hCG.A total laparoscopic hysterectomy is recommended.展开更多
BACKGROUND Hepatic epithelioid angiomyolipoma(HEA)has a low incidence and both clinical manifestations and imaging lack specificity.Thus,it is easy to misdiagnose HEA as other tumors of the liver,especially in the pre...BACKGROUND Hepatic epithelioid angiomyolipoma(HEA)has a low incidence and both clinical manifestations and imaging lack specificity.Thus,it is easy to misdiagnose HEA as other tumors of the liver,especially in the presence of liver diseases such as hepatitis cirrhosis.This article reviewed the diagnosis and treatment of a patient with HEA and alcoholic cirrhosis,and analyzed the literature,in order to improve the understanding of this disease.CASE SUMMARY A 67-year-old male patient with a history of alcoholic cirrhosis was admitted due to the discovery of a space-occupying lesion in the liver.Based on the patient’s history,laboratory examinations,and imaging examinations,a malignant liver tumor was considered and laparoscopic partial hepatectomy was performed.Postoperative pathology showed HEA.During outpatient follow-up,the patient showed no sign of recurrence.CONCLUSION HEA is difficult to make a definite diagnosis before surgery.HEA has the poten-tial for malignant degeneration.If conditions permit,surgical treatment is recom-mended.展开更多
BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including ...BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including its clinical manifestations,preoperative imaging features,gross specimen and pathological findings.CASE SUMMARY A 33-year-old male patient was admitted to Peking Union Medical College Hospital in December 2023 due to a one-year history of intermittent upper abdominal pain and the discovery of a pancreatic mass.The patient underwent an enhanced computed tomography scan of the abdomen,which revealed a welldefined,round mass with clear borders and calcifications in the pancreatic head.The mass exhibited progressive,uneven mild enhancement,measuring approximately 6.6 cm×6.3 cm.The patient underwent laparoscopic pylorus-preserving pancreaticoduodenectomy.Postoperative pathological examination revealed that the lesion was consistent with a SEF.At the 3-month postoperative follow-up,the patient did not report any short-term complications,and there were no signs of tumor recurrence.CONCLUSION SEFs are rare malignant fibrous soft tissue tumors.SEFs rarely develop in the pancreas,and its preoperative diagnosis depends on imaging findings,with confirmation depending on pathological examination and immunohistochemistry.Currently,only four cases of pancreatic SEF have been reported in studies written in English.This case is the first reported case of a pancreatic SEF by a clinical physician.展开更多
Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical info...Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical information of 23 patients with CHM were retrospectively analyzed.Results:CT examinations were conducted in 7 cases,while MRI was utilized in 23 cases.Additionally,SWI was employed in 5 cases and enhanced imaging techniques were applied in 14 cases.Among the observed lesions,20 cases presented with a singular lesion,whereas 3 cases exhibited multiple lesions.The lesions were located in 8 frontal lobes,6 cerebellums,2 brainstems,6 temporal lobes,1 basal ganglia,3 parieto-occipital lobes,and 2 thalamus regions.The nodules appeared as quasi-circular lesions with clear or well-defined boundaries.They presented as isodense lesions on CT scans,with one lesion showing peritumoral edema.On MRI,T1-weighted imaging(T1WI)demonstrated isointense signals,while T2-weighted imaging(T2WI)showed isointense and hyperintense signals.Additionally,10 lesions exhibited a low signal ring on T2WI.Diffusion-weighted imaging(DWI)revealed nodular or isointense low signals,while susceptibility-weighted imaging(SWI)displayed enlarged areas of low signal.Fourteen lesions underwent contrast-enhanced scanning,with 2 lesions showing no obvious enhancement,1 lesion demonstrating mild to moderate enhancement,and 11 lesions exhibiting significant enhancement.Notably,6 of these enhanced lesions were surrounded by small blood vessels.Conclusion:Cavernous hemangioma malformation is more commonly found in individual cases.CT alone lacks specificity,making it prone to misdiagnosis.A more comprehensive evaluation of cavernous hemangioma malformation can be achieved through a combination of MRI,DWI,SWI,and enhanced examination,providing valuable references for clinical assessment.展开更多
BACKGROUND Renal anastomosing hemangioma(AH)is a rare benign vascular tumor characterized by unique histopathological features.CASE SUMMARY We report a highly unusual case of renal AH.A male patient had undergone part...BACKGROUND Renal anastomosing hemangioma(AH)is a rare benign vascular tumor characterized by unique histopathological features.CASE SUMMARY We report a highly unusual case of renal AH.A male patient had undergone partial nephrectomy for clear cell carcinoma of the kidney four years prior.A follow-up computed tomography scan in the third postoperative year revealed a new mass near the surgical site on the same side of the kidney,raising suspicions of tumor recurrence.However,the characteristics on contrast-enhanced magnetic resonance imaging and ultrasonography were more consistent with those of a benign lesion.The patient strongly insisted on undergoing surgery due to concerns about the possibility of renal cancer recurrence.Postoperative pathology confirmed the diagnosis of renal AH.CONCLUSION This case report presents the imaging features of a patient with rare renal AH and a history of renal clear cell carcinoma,providing broader insights into the differential diagnosis of new lesions after surgery for renal cell carcinoma.展开更多
To the Editor:Hemangioma is a benign liver tumor that rarely requires treatment if the patient is asymptomatic[1].However,great cavernous hemangioma(GCH)can lead to symptoms due to its mass effect and Kasabach-Merritt...To the Editor:Hemangioma is a benign liver tumor that rarely requires treatment if the patient is asymptomatic[1].However,great cavernous hemangioma(GCH)can lead to symptoms due to its mass effect and Kasabach-Merritt syndrome(KMS)[2].GCH treatment options vary;therefore,tailoring treatment to individual patients according to their condition,such as symptoms,tumor location,and liver function,is important.Occasionally,GCH is associated with hemangiomatosis,and its boundaries with normal tissue are unclear[3],leading to a lack of consensus on the initial therapeutic approach,with literature primarily comprising case reports or series[4].This study presented two cases of GCH and coexisting hemangiomatosis;the patients underwent liver resection of the main mass to relieve symptoms but ultimately required liver transplantation(LT).We aimed to describe the role of LT in these patients.展开更多
Although rare, intraneural hemangiomas should be considered in the differential diagnosis of peripheral nerve lesions. We report on a 59-year-old female patient, who was admitted to the hospital due to the discovery o...Although rare, intraneural hemangiomas should be considered in the differential diagnosis of peripheral nerve lesions. We report on a 59-year-old female patient, who was admitted to the hospital due to the discovery of bilateral breast masses for 3 months, there was no paresthesia or dyskinesia. The patient accidentally found a mass in the right upper mediastinum while completing a plain chest X-ray, initially suspected as a benign neurilemmoma on CT. Surgical resection and pathological analysis confirmed an intraneural hemangioma. Unexpectedly, the patient developed new-onset right upper limb numbness and paresthesia 3 months post-operatively, probably related to surgical nerve injury. This case underscores the importance of maintaining a broad differential for mediastinal masses, and the potential for iatrogenic neurological complications when managing these rare, yet vascular lesions.展开更多
AIM: To improve the clinical diagnosis and recognition of hepatic epithelioid angiomyolipoma(HEAML).METHODS: Four cases of primary HEAML were confirmed based on the pathology archive system in our hospital from Januar...AIM: To improve the clinical diagnosis and recognition of hepatic epithelioid angiomyolipoma(HEAML).METHODS: Four cases of primary HEAML were confirmed based on the pathology archive system in our hospital from January 2009 to November 2015. The general state, clinical symptoms, imaging manifestations, histological results and immunohistochemistry of these patients were retrospectively reviewed and analyzed. Studies of HEAML published in the last 15 years were collected from Pub Med and MEDLINE to summarize the clinical symptoms, imaging characteristics, pathological features and management of HEAML.RESULTS: Four cases of primary HEAML were retrieved from our archives. These included three female patients and one male patient, with a mean age of 41.8 ± 11.5 years(ranging from 31 to 56 years). The meantumor size was 7.3 ± 5.5 cm(ranging from 3.0 to 15 cm). In the contrast-enhanced imaging, the tumor was obviously enhanced in the arterial phase, but enhanced continuously or exhibited a slow-density masse during the venous and delayed phases. Histologically, the tumors mainly consisted of epithelioid cells that comprised approximately 95% of the total neoplastic mass. Although no metastases occurred in our patients, pathological studies revealed necrosis, mitotic figures and liver invasion in two patients, which indicates aggressive behavior. Immunohistochemical staining revealed that human melanoma black 45(HMB-45) and Melan-A were positive in 4 cases. We only identified 81 cases with primary HEAML, including our present patients, from 26 articles available from Pub Med and MEDLINE. The majority of the papers were published as case reports. Only 5(5/75, 6%) cases were associated with tuberous sclerosis complex(TSC). More than half(35/66) were discovered incidentally upon physical examination. Approximately 65%(22/34) of the patients were misdiagnosed with HCC or other tumors before surgery. Approximately 10%(8/81) of the patients with HEAML had recurrence or metastasis after surgery, which was a very high and alarming rate.CONCLUSION: HEAML is a very rare primary hepatic tumor that is often misdiagnosed before surgery. Patients should be followed closely after surgery because of its malignant potential.展开更多
A 58-year-old man presented with the chief complaint of abdominal bloating and was incidentally found to have a liver tumor.As diagnostic imaging studies could not rule out malignancy,the patient underwent partial res...A 58-year-old man presented with the chief complaint of abdominal bloating and was incidentally found to have a liver tumor.As diagnostic imaging studies could not rule out malignancy,the patient underwent partial resection of segment 3 of the liver.The lesion pathologically showed eosinophilic proliferation,in addition to immunohistochemical positivity for human melanoma black 45 and Melan-A,thereby leading to the diagnosis of a hepatic perivascular epithelioid cell tumor(PEComa).A PEComa arising from the liver is relatively rare.Moreover,the name ‘PEComa' has not yet been widely recognized,and the same disease entity has been called epithelioid angiomyolipoma(EAML),further diminishing the recognition of PEComa.In addition,PEComa imaging findings mimic those of malignant liver tumors,and clinically,this tumor tends to enlarge.Therefore,a PEComa is difficult to diagnose.We conducted a systematic review of PEComa and EAML cases and discuss the results,including findings useful for differentiating perivascular epithelioid cell tumors from malignant liver tumors.展开更多
AIM: To explore the characteristics of multi-slice computed tomography (CT) manifestations of hepatic epithelioid angiomyolipoma (HEA), improve the rate of accurate diagnosis, and reduce the misdiagnostic rate.
BACKGROUND: Hepatic epithelioid hemangioendothelioma (EHE) is a rare, low-grade malignant vascular tumor. Although its unusual imaging and pathologic findings are being recognized with increasing frequency, diagnosis ...BACKGROUND: Hepatic epithelioid hemangioendothelioma (EHE) is a rare, low-grade malignant vascular tumor. Although its unusual imaging and pathologic findings are being recognized with increasing frequency, diagnosis is still difficult. This study aimed to analyze the CT and MRI features of hepatic EHE with a pathological study in order to improve the diagnostic accuracy and knowledge of this disease in daily practice. METHODS: Nine patients with hepatic EHE confirmed pathologically underwent plain and dynamic contrast-enhanced multi-detector row CT examination. Of these patients, four underwent additional MRI (plain Ti-weighted imaging (T1WI), T2-weighted imaging (T2WI), and dynamic contrast-enhanced scanning) and one had selective hepatic arteriography. The imaging findings were reviewed retrospectively together with the pathological results. RESULTS: A total of 79 lesions, ranging from 3.0 to 44.6 mm in maximum diameter, with an average of 16.8 +/- 7.1 mm, were found in various segments of the liver. Thirty of the 79 lesions grew adjacent to the hepatic capsule. In the 4 patients receiving MRI, 39 lesions were found with low signal intensity on unenhanced T1WI and intermediate to high signal intensity on T2WI. The 'capsular retraction' sign was found in all the 4 patients. Nine of the 39 lesions showed the 'halo' sign after contrast enhancement on MRI. Of the 79 lesions (hypodense nodules) in the 9 patients shown by unenhanced plain CT, 26 were confluent. Calcification was found in 2 patients and the 'capsular retraction' sign in 7. Thirty-eight of the 79 lesions demonstrated the 'halo' sign after contrast enhancement on CT, and this sign was more clearly demonstrated in the portal venous phase. In one patient, selective hepatic arteriography showed patchy stain in the peripheral liver parenchyma with small vessels around them. Histology in all patients revealed proliferation of abnormal fibrous tissue and vessel-like structures scattered with irregular epithelioid cells having a signet ring-like structure. Immunohistochemically, all patients were positive for CD34, 4 were positive for CD31, and 3 were positive for factor VIII-related antigen. CONCLUSIONS: Hepatic EHE may manifest as solitary or diffuse nodular lesions with a predilection for peripheral subcapsular growth and nodular confluence, together with the 'halo' and 'capsular retraction' signs. These imaging findings can help to improve the diagnostic accuracy of this rare hepatic tumor. (Hepatobiliary Pancreat Dis Int 2010; 9: 154-158)展开更多
Epithelioid hemangioendothelioma(EH)is a rare tumor arising from the vascular endothelial cells of soft tissue or visceral organs.The most common visceral site is the liver,where it is often involved in a multifocal m...Epithelioid hemangioendothelioma(EH)is a rare tumor arising from the vascular endothelial cells of soft tissue or visceral organs.The most common visceral site is the liver,where it is often involved in a multifocal man-ner known as hepatic EH(HEH).Surgical resection with curative intent represents the gold standard therapy.When surgery is not feasible,or in cases of metastatic disease,no standard medical treatment is currently indicated.In small series,drugs with anti-angiogenic activity(such as bevacizumab,sorafenib,thalidomide,and lenalidomide)have been proposed with promising results.We describe a 73-year-old man with multifocal non-resectable HEH treated with lenalidomide.Disease status was evaluated by abdominal ultrasound and magnetic resonance every four months.The patient was treated for a total of 39 mo with prolonged disease stabilization and,at the time of writing,is still under treatment with a good tolerance profile.During a short period of treatment discontinuation,the disease showed slight progression that immediately resolved after the reintroduction of lenalidomide.Lenalidomide may represent a valid treatment option for HEH due to its anti-angiogenic and antineoplastic activities.This preliminary result merits further study in a large series.展开更多
Background: Hepatic epithelioid hemangioendothelioma (HEH) is a rare tumor of vascular origin with an unknown etiology, a low incidence, and a variable natural course. We evaluated the management and prognosis of HEH ...Background: Hepatic epithelioid hemangioendothelioma (HEH) is a rare tumor of vascular origin with an unknown etiology, a low incidence, and a variable natural course. We evaluated the management and prognosis of HEH from the Surveillance, Epidemiology and End Results (SEER) program and changes in treatment modalities of HEH over 30 years. Methods: From 1973 to 2014 in the SEER database, we selected patients diagnosed with HEH. We analyzed the clinical characteristics, patterns of management, and clinical outcomes of patients with HEH. Results: We identi ed 79 patients with HEH (median age: 54.0 years;male to female ratio: 1:2.6). The initial extent of disease was local in 22 (27.8%) patients, regional metastasis in 22 (27.8%), distant metas-tasis in 31 (39.2%) and unknown in 4 (5.1%). The median size of primary tumor was 3.85 cm (interquartile range, 2.50 7.93 cm). Among 74 patients with available management data, the most common manage-ment was no treatment (29/74, 39.2%), followed by chemotherapy only (22/74, 29.7%), liver resection-based (13/74, 17.6%), and transplantation-based therapy (6/74, 8.1%). The 5-year cancer-speci c survival rate was 57.8%. Patients who underwent surgical treatment had signi cantly higher survival than those who underwent non-surgical treatment (5-year survival;88% vs. 49%, P=0.019). Multivariate analysis revealed that surgical therapy was the only independent prognostic factor for survival (hazard ratio: 0.20, P=0.040). Conclusions: Resection or liver transplantation is worth considering for treatment of patients with HEH.展开更多
BACKGROUND Hepatic epithelioid angiomyolipoma(HEAML) is a rare liver disease and is easily misdiagnosed. Enhanced recognition of HEAML is beneficial to the differential diagnosis of rare liver diseases.CASE SUMMARY We...BACKGROUND Hepatic epithelioid angiomyolipoma(HEAML) is a rare liver disease and is easily misdiagnosed. Enhanced recognition of HEAML is beneficial to the differential diagnosis of rare liver diseases.CASE SUMMARY We presented two cases of HEAML in Changzheng Hospital, Naval Medical University, and then collected and analyzed all reports about HEAML recorded in PubMed, MEDLINE, China Science Periodical Database, and VIP database from January 2000 to March 2018. A total of 409 cases of HEAML in 97 reports were collected, with a ratio of men to women of 1:4.84 and an age range from 12 years to 80 years(median 44 years). Among the patients with clinical symptoms mentioned, 61.93%(205/331) were asymptomatic, 34.74%(115/331) showed upper or right upper quadrant abdomen discomfort, while a few of them showed abdominal mass, gastrointestinal symptoms, low fever, or weight loss. The misdiagnosis rate of HEAML was as high as 40.34%(165/409) due to its nonspecific imaging findings. Most of the tumors were solitary and round in morphology, with clear boundaries. Ultrasound scan indicated low echo with internal nonuniformity and rich blood supply in most cases. Computer tomography/magnetic resonance imaging enhanced scan showed varied characteristics. The ratio of fast wash-in and fast wash-out, fast wash-in and slow wash-out, and delayed enhancement was roughly 4:5:1. A definite diagnosis of HEAML depended on the pathological findings of the epithelioid cells in lesions and the expression of human melanoma black 45, smooth muscle actin,melanoma antigen, and actin by immunohistochemical staining. HEAML had a relatively low malignant rate of 3.91%. However, surgical resection was the main treatment for HEAML, due to the difficulty diagnosing before operation.CONCLUSION HEAML is a rare and easily misdiagnosed disease, and it should be diagnosed carefully, taking into account clinical course, imaging, pathological,and immunohistochemical findings.展开更多
Perivascular epithelioid cell tumor(PEComa) is a rare mesenchymal neoplasia and currently well recognized as a distinct entity with characteristic morphological,immunohistochemical and molecular findings.We report a c...Perivascular epithelioid cell tumor(PEComa) is a rare mesenchymal neoplasia and currently well recognized as a distinct entity with characteristic morphological,immunohistochemical and molecular findings.We report a case of PEComa arising in the antrum of a 71-year-old female with melena.The tumor,located predominantly in the submucosa as a well delimited nodule,measured 3.0 cm in diameter and was completely resected,with no evidence of the disease elsewhere.Histologically,it was composed predominantly of eosinophilic epithelioid cells arranged in small nests commonly related to variably sized vessels,with abundant extracellular material,moderate nuclear variation and discrete mitotic activity.No necrosis,angiolymphatic invasion or perineural infil-tration was seen.Tumor cells were uniformly positive for vimentin,smooth muscle actin,desmin and melan A.Although unusual,PEComa should be considered in the differential diagnosis of gastric neoplasia with characteristic epithelioid and oncocytic features and prominent vasculature.展开更多
文摘Renal anastomotic hemangioma(AH)is a rare,benign vascular tumor with unique histopathological features,a disease that is clinically rare,and existing clinical cases offer different treatment options.As reported in the text,this is a very unusual case of renal AH with AH secondary to residual renal tissue after renal clear cell carcinoma,describing a rare renal AH and a history of renal clear cell carcinoma,including ultrasound,computed tomography and magnetic re-sonance imaging.However,the available imaging data and the literature do not provide an effective basis for the diagnosis of the disease,raising the lack of un-derstanding and misdiagnosis,where the patient eventually underwent neph-rectomy,but the author is not the most appropriate surgical treatment.The po-stoperative pathological results of the patient are benign lesions,and it is unde-niable that nephrectomy is suspected to be overtreated.By reading the literature,we provide different insights into the treatment of the patient,and we hope that this paper can provide some help for the future clinical diagnosis and treatment.
基金Supported by the Natural Science Foundation of Zhejiang Province,No.LQ20H030007 and No.LY20H030010the Zhejiang Medical Health Technology Project,No.2019KY393.
文摘BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric SMTs.CASE SUMMARY We describe two cases of gastric SMT-like protrusions initially misdiagnosed as gastric SMTs by the abdominal contrast-enhanced computed tomography(CT)and endoscopic ultrasound(EUS).Based on the CT and EUS findings,the patients underwent gastroscopy;however,no tumor was identified after incising the gastric wall.Subsequent surgical exploration revealed no gastric lesions in both patients,but a mass was found in the left triangular ligament of the liver.The patients underwent laparoscopic tumor resection,and the postoperative diagnosis was hepatic hemangiomas.CONCLUSION During EUS procedures,scanning across different layers and at varying degrees of gastric cavity distension,coupled with meticulous image analysis,has the potential to mitigate the likelihood of such misdiagnoses.
基金Supported by Nantong Municipal Health Commission,No.MSZ2022036.
文摘Accurate preoperative diagnosis is highly important for the treatment of perivascular epithelioid cell tumors(PEComas)because PEComas are mainly benign tumors and may not require surgical intervention.By analyzing the causes,properties and clinical manifestations of PEComas,we summarize the challenges and solutions in the diagnosis of PEComas.
文摘BACKGROUND Epithelioid malignant peripheral nerve sheath tumor(EMPNST)of the bladder is a rare entity with devastating features.These tumors are thought to originate from malignant transformation of pre-existing schwannomas of pelvic autonomic nerve plexuses,and unlike the conventional malignant peripheral nerve sheath tumor(MPNST),are not associated with neurofibromatosis.The tumor has dis-tinctive morphological,immunohistochemical and molecular features.Addi-tionally,it tends to be more aggressive and have a higher mortality.This is the first case that presents with a synchronous urothelial carcinoma of the bladder and the epithelioid variant of MPNST in the literature.It’s also the second re-ported case of EMPNST originating from the bladder wall.CASE SUMMARY In this case report,we present the detailed clinical course of a 71-year-old patient with EMPNST of the bladder alongside a literature review.CONCLUSION During the management of EMPNST cases,offering aggressive treatment moda-lities to the patient,such as radical cystectomy,is appropriate for the best chance to contain the disease,regardless of the tumor stage and the extent of local disease at initial diagnosis.
基金Supported by Cuiying Scientific and Technological Innovation Program of Lanzhou University Second Hospital,No.CY2022-QN-A13 and No.CY2023-QN-A02Lanzhou Science and Technology Plan Project,No.2023-4-26+1 种基金Gansu Provincial Natural Science Foundation Project,No.23JRRA1630 and No.24JRRA331Gansu Provincial Health Research Program Project,No.GSWSKY-2019-32.
文摘BACKGROUND Perivascular epithelioid cell tumor(PEComa)is a rare mesenchymal neoplasm that predominantly affects the kidney and uterus.The occurrence of this tumor in the liver,particularly with simultaneous involvement of the liver and kidney,is exceedingly uncommon.Pathological diagnosis is the gold standard.PEComas usually show positive immunohistochemical staining for melanocytic(HMB-45,Melan-A)and myoid(SMA,muscle-specific actin)markers.CASE SUMMARY We presented a noteworthy case of malignant PEComa affecting both the liver and kidney in a 53-year-old man with tuberous sclerosis complex(TSC).FAT2 and TP73 mutations in the kidney were identified and positive expression of diagnostic markers including HMB-45,Melan A,and TFE3 were detected.In addition,we demonstrated that hepatic artery perfusion chemotherapy was ineffective for hepatic PEComa,while surgery remained the most effective approach.Everolimus showed an excellent efficacy in the postoperative treatment of the tumor.CONCLUSION Surgical treatment is preferred for malignant PEComa affecting liver and kidney,especially with TSC;everolimus is effective postoperatively.
文摘BACKGROUND Epithelioid trophoblastic tumor(ETT)is an extremely rare malignant gestational trophoblastic neoplasm commonly presenting with abnormal vaginal bleeding,abdominal pain,and increased human chorionic gonadotropin(hCG).This study reported a case of uterine ETT with the main manifestation being increased hCG.CASE SUMMARY A 39-year-old female was referred to the Ningbo Maternal and Child Hospital of China in December 2022,complaining of increased hCG levels for 1 month.Magnetic resonance imaging revealed gestational trophoblastic tumor,and hysteroscopic electrotomy and curettage of intrauterine hyperplasia were performed.The patient was diagnosed with uterine ETT through postoperative pathological examination and immunohistochemical results.Total laparoscopic hysterectomy and bilateral salpingectomy were performed,and hCG levels returned to normal.The patient was without recurrence during the postoperative 3-month follow-up.CONCLUSION This study reported a case of uterine ETT with the main manifestation being increased hCG,highlighting that ETT should be considered in the presence of abnormal hCG.A total laparoscopic hysterectomy is recommended.
基金Supported by Natural Science Foundation of Zhejiang Province,No.LY19H030004and The Lishui City Key Research and Ddevelopment Project,No.2022ZDYF08。
文摘BACKGROUND Hepatic epithelioid angiomyolipoma(HEA)has a low incidence and both clinical manifestations and imaging lack specificity.Thus,it is easy to misdiagnose HEA as other tumors of the liver,especially in the presence of liver diseases such as hepatitis cirrhosis.This article reviewed the diagnosis and treatment of a patient with HEA and alcoholic cirrhosis,and analyzed the literature,in order to improve the understanding of this disease.CASE SUMMARY A 67-year-old male patient with a history of alcoholic cirrhosis was admitted due to the discovery of a space-occupying lesion in the liver.Based on the patient’s history,laboratory examinations,and imaging examinations,a malignant liver tumor was considered and laparoscopic partial hepatectomy was performed.Postoperative pathology showed HEA.During outpatient follow-up,the patient showed no sign of recurrence.CONCLUSION HEA is difficult to make a definite diagnosis before surgery.HEA has the poten-tial for malignant degeneration.If conditions permit,surgical treatment is recom-mended.
基金Supported by National High Level Hospital Clinical Research Funding,No.2022-PUMCH-B-003National Multidisciplinary Cooperative Diagnosis and Treatment Capacity Building Project for Major Diseases.
文摘BACKGROUND A sclerosing epithelioid fibrosarcoma(SEF)is a rare malignant fibroblastic soft tissue tumor that rarely occurs in intra-abdominal organs.A case of a SEF in the pancreatic head is reported herein,including its clinical manifestations,preoperative imaging features,gross specimen and pathological findings.CASE SUMMARY A 33-year-old male patient was admitted to Peking Union Medical College Hospital in December 2023 due to a one-year history of intermittent upper abdominal pain and the discovery of a pancreatic mass.The patient underwent an enhanced computed tomography scan of the abdomen,which revealed a welldefined,round mass with clear borders and calcifications in the pancreatic head.The mass exhibited progressive,uneven mild enhancement,measuring approximately 6.6 cm×6.3 cm.The patient underwent laparoscopic pylorus-preserving pancreaticoduodenectomy.Postoperative pathological examination revealed that the lesion was consistent with a SEF.At the 3-month postoperative follow-up,the patient did not report any short-term complications,and there were no signs of tumor recurrence.CONCLUSION SEFs are rare malignant fibrous soft tissue tumors.SEFs rarely develop in the pancreas,and its preoperative diagnosis depends on imaging findings,with confirmation depending on pathological examination and immunohistochemistry.Currently,only four cases of pancreatic SEF have been reported in studies written in English.This case is the first reported case of a pancreatic SEF by a clinical physician.
文摘Objective:To investigate the computed tomography(CT)and magnetic resonance imaging(MRI)features of cavernous hemangioma malformation(CHM)to enhance diagnostic accuracy.Methods:The CT and MRI findings and clinical information of 23 patients with CHM were retrospectively analyzed.Results:CT examinations were conducted in 7 cases,while MRI was utilized in 23 cases.Additionally,SWI was employed in 5 cases and enhanced imaging techniques were applied in 14 cases.Among the observed lesions,20 cases presented with a singular lesion,whereas 3 cases exhibited multiple lesions.The lesions were located in 8 frontal lobes,6 cerebellums,2 brainstems,6 temporal lobes,1 basal ganglia,3 parieto-occipital lobes,and 2 thalamus regions.The nodules appeared as quasi-circular lesions with clear or well-defined boundaries.They presented as isodense lesions on CT scans,with one lesion showing peritumoral edema.On MRI,T1-weighted imaging(T1WI)demonstrated isointense signals,while T2-weighted imaging(T2WI)showed isointense and hyperintense signals.Additionally,10 lesions exhibited a low signal ring on T2WI.Diffusion-weighted imaging(DWI)revealed nodular or isointense low signals,while susceptibility-weighted imaging(SWI)displayed enlarged areas of low signal.Fourteen lesions underwent contrast-enhanced scanning,with 2 lesions showing no obvious enhancement,1 lesion demonstrating mild to moderate enhancement,and 11 lesions exhibiting significant enhancement.Notably,6 of these enhanced lesions were surrounded by small blood vessels.Conclusion:Cavernous hemangioma malformation is more commonly found in individual cases.CT alone lacks specificity,making it prone to misdiagnosis.A more comprehensive evaluation of cavernous hemangioma malformation can be achieved through a combination of MRI,DWI,SWI,and enhanced examination,providing valuable references for clinical assessment.
文摘BACKGROUND Renal anastomosing hemangioma(AH)is a rare benign vascular tumor characterized by unique histopathological features.CASE SUMMARY We report a highly unusual case of renal AH.A male patient had undergone partial nephrectomy for clear cell carcinoma of the kidney four years prior.A follow-up computed tomography scan in the third postoperative year revealed a new mass near the surgical site on the same side of the kidney,raising suspicions of tumor recurrence.However,the characteristics on contrast-enhanced magnetic resonance imaging and ultrasonography were more consistent with those of a benign lesion.The patient strongly insisted on undergoing surgery due to concerns about the possibility of renal cancer recurrence.Postoperative pathology confirmed the diagnosis of renal AH.CONCLUSION This case report presents the imaging features of a patient with rare renal AH and a history of renal clear cell carcinoma,providing broader insights into the differential diagnosis of new lesions after surgery for renal cell carcinoma.
文摘To the Editor:Hemangioma is a benign liver tumor that rarely requires treatment if the patient is asymptomatic[1].However,great cavernous hemangioma(GCH)can lead to symptoms due to its mass effect and Kasabach-Merritt syndrome(KMS)[2].GCH treatment options vary;therefore,tailoring treatment to individual patients according to their condition,such as symptoms,tumor location,and liver function,is important.Occasionally,GCH is associated with hemangiomatosis,and its boundaries with normal tissue are unclear[3],leading to a lack of consensus on the initial therapeutic approach,with literature primarily comprising case reports or series[4].This study presented two cases of GCH and coexisting hemangiomatosis;the patients underwent liver resection of the main mass to relieve symptoms but ultimately required liver transplantation(LT).We aimed to describe the role of LT in these patients.
文摘Although rare, intraneural hemangiomas should be considered in the differential diagnosis of peripheral nerve lesions. We report on a 59-year-old female patient, who was admitted to the hospital due to the discovery of bilateral breast masses for 3 months, there was no paresthesia or dyskinesia. The patient accidentally found a mass in the right upper mediastinum while completing a plain chest X-ray, initially suspected as a benign neurilemmoma on CT. Surgical resection and pathological analysis confirmed an intraneural hemangioma. Unexpectedly, the patient developed new-onset right upper limb numbness and paresthesia 3 months post-operatively, probably related to surgical nerve injury. This case underscores the importance of maintaining a broad differential for mediastinal masses, and the potential for iatrogenic neurological complications when managing these rare, yet vascular lesions.
文摘AIM: To improve the clinical diagnosis and recognition of hepatic epithelioid angiomyolipoma(HEAML).METHODS: Four cases of primary HEAML were confirmed based on the pathology archive system in our hospital from January 2009 to November 2015. The general state, clinical symptoms, imaging manifestations, histological results and immunohistochemistry of these patients were retrospectively reviewed and analyzed. Studies of HEAML published in the last 15 years were collected from Pub Med and MEDLINE to summarize the clinical symptoms, imaging characteristics, pathological features and management of HEAML.RESULTS: Four cases of primary HEAML were retrieved from our archives. These included three female patients and one male patient, with a mean age of 41.8 ± 11.5 years(ranging from 31 to 56 years). The meantumor size was 7.3 ± 5.5 cm(ranging from 3.0 to 15 cm). In the contrast-enhanced imaging, the tumor was obviously enhanced in the arterial phase, but enhanced continuously or exhibited a slow-density masse during the venous and delayed phases. Histologically, the tumors mainly consisted of epithelioid cells that comprised approximately 95% of the total neoplastic mass. Although no metastases occurred in our patients, pathological studies revealed necrosis, mitotic figures and liver invasion in two patients, which indicates aggressive behavior. Immunohistochemical staining revealed that human melanoma black 45(HMB-45) and Melan-A were positive in 4 cases. We only identified 81 cases with primary HEAML, including our present patients, from 26 articles available from Pub Med and MEDLINE. The majority of the papers were published as case reports. Only 5(5/75, 6%) cases were associated with tuberous sclerosis complex(TSC). More than half(35/66) were discovered incidentally upon physical examination. Approximately 65%(22/34) of the patients were misdiagnosed with HCC or other tumors before surgery. Approximately 10%(8/81) of the patients with HEAML had recurrence or metastasis after surgery, which was a very high and alarming rate.CONCLUSION: HEAML is a very rare primary hepatic tumor that is often misdiagnosed before surgery. Patients should be followed closely after surgery because of its malignant potential.
文摘A 58-year-old man presented with the chief complaint of abdominal bloating and was incidentally found to have a liver tumor.As diagnostic imaging studies could not rule out malignancy,the patient underwent partial resection of segment 3 of the liver.The lesion pathologically showed eosinophilic proliferation,in addition to immunohistochemical positivity for human melanoma black 45 and Melan-A,thereby leading to the diagnosis of a hepatic perivascular epithelioid cell tumor(PEComa).A PEComa arising from the liver is relatively rare.Moreover,the name ‘PEComa' has not yet been widely recognized,and the same disease entity has been called epithelioid angiomyolipoma(EAML),further diminishing the recognition of PEComa.In addition,PEComa imaging findings mimic those of malignant liver tumors,and clinically,this tumor tends to enlarge.Therefore,a PEComa is difficult to diagnose.We conducted a systematic review of PEComa and EAML cases and discuss the results,including findings useful for differentiating perivascular epithelioid cell tumors from malignant liver tumors.
基金Supported by Jilin Provincial Science and Technology Department,No.201015158 and No.20110922Jilin Provincial Administration of Traditional Chinese Medicine,No.2011-JS20
文摘AIM: To explore the characteristics of multi-slice computed tomography (CT) manifestations of hepatic epithelioid angiomyolipoma (HEA), improve the rate of accurate diagnosis, and reduce the misdiagnostic rate.
文摘BACKGROUND: Hepatic epithelioid hemangioendothelioma (EHE) is a rare, low-grade malignant vascular tumor. Although its unusual imaging and pathologic findings are being recognized with increasing frequency, diagnosis is still difficult. This study aimed to analyze the CT and MRI features of hepatic EHE with a pathological study in order to improve the diagnostic accuracy and knowledge of this disease in daily practice. METHODS: Nine patients with hepatic EHE confirmed pathologically underwent plain and dynamic contrast-enhanced multi-detector row CT examination. Of these patients, four underwent additional MRI (plain Ti-weighted imaging (T1WI), T2-weighted imaging (T2WI), and dynamic contrast-enhanced scanning) and one had selective hepatic arteriography. The imaging findings were reviewed retrospectively together with the pathological results. RESULTS: A total of 79 lesions, ranging from 3.0 to 44.6 mm in maximum diameter, with an average of 16.8 +/- 7.1 mm, were found in various segments of the liver. Thirty of the 79 lesions grew adjacent to the hepatic capsule. In the 4 patients receiving MRI, 39 lesions were found with low signal intensity on unenhanced T1WI and intermediate to high signal intensity on T2WI. The 'capsular retraction' sign was found in all the 4 patients. Nine of the 39 lesions showed the 'halo' sign after contrast enhancement on MRI. Of the 79 lesions (hypodense nodules) in the 9 patients shown by unenhanced plain CT, 26 were confluent. Calcification was found in 2 patients and the 'capsular retraction' sign in 7. Thirty-eight of the 79 lesions demonstrated the 'halo' sign after contrast enhancement on CT, and this sign was more clearly demonstrated in the portal venous phase. In one patient, selective hepatic arteriography showed patchy stain in the peripheral liver parenchyma with small vessels around them. Histology in all patients revealed proliferation of abnormal fibrous tissue and vessel-like structures scattered with irregular epithelioid cells having a signet ring-like structure. Immunohistochemically, all patients were positive for CD34, 4 were positive for CD31, and 3 were positive for factor VIII-related antigen. CONCLUSIONS: Hepatic EHE may manifest as solitary or diffuse nodular lesions with a predilection for peripheral subcapsular growth and nodular confluence, together with the 'halo' and 'capsular retraction' signs. These imaging findings can help to improve the diagnostic accuracy of this rare hepatic tumor. (Hepatobiliary Pancreat Dis Int 2010; 9: 154-158)
文摘Epithelioid hemangioendothelioma(EH)is a rare tumor arising from the vascular endothelial cells of soft tissue or visceral organs.The most common visceral site is the liver,where it is often involved in a multifocal man-ner known as hepatic EH(HEH).Surgical resection with curative intent represents the gold standard therapy.When surgery is not feasible,or in cases of metastatic disease,no standard medical treatment is currently indicated.In small series,drugs with anti-angiogenic activity(such as bevacizumab,sorafenib,thalidomide,and lenalidomide)have been proposed with promising results.We describe a 73-year-old man with multifocal non-resectable HEH treated with lenalidomide.Disease status was evaluated by abdominal ultrasound and magnetic resonance every four months.The patient was treated for a total of 39 mo with prolonged disease stabilization and,at the time of writing,is still under treatment with a good tolerance profile.During a short period of treatment discontinuation,the disease showed slight progression that immediately resolved after the reintroduction of lenalidomide.Lenalidomide may represent a valid treatment option for HEH due to its anti-angiogenic and antineoplastic activities.This preliminary result merits further study in a large series.
基金supported by the Bio&Medical Tech-nology Development Program of the National Research Foun-dation(NRF)funded by the Korean government(MSIT)(NRF-2018M3A9E8023861)by a grant from the Korean Health R&D Project.Ministry of Health Welfare,Korea(HI18C0531)
文摘Background: Hepatic epithelioid hemangioendothelioma (HEH) is a rare tumor of vascular origin with an unknown etiology, a low incidence, and a variable natural course. We evaluated the management and prognosis of HEH from the Surveillance, Epidemiology and End Results (SEER) program and changes in treatment modalities of HEH over 30 years. Methods: From 1973 to 2014 in the SEER database, we selected patients diagnosed with HEH. We analyzed the clinical characteristics, patterns of management, and clinical outcomes of patients with HEH. Results: We identi ed 79 patients with HEH (median age: 54.0 years;male to female ratio: 1:2.6). The initial extent of disease was local in 22 (27.8%) patients, regional metastasis in 22 (27.8%), distant metas-tasis in 31 (39.2%) and unknown in 4 (5.1%). The median size of primary tumor was 3.85 cm (interquartile range, 2.50 7.93 cm). Among 74 patients with available management data, the most common manage-ment was no treatment (29/74, 39.2%), followed by chemotherapy only (22/74, 29.7%), liver resection-based (13/74, 17.6%), and transplantation-based therapy (6/74, 8.1%). The 5-year cancer-speci c survival rate was 57.8%. Patients who underwent surgical treatment had signi cantly higher survival than those who underwent non-surgical treatment (5-year survival;88% vs. 49%, P=0.019). Multivariate analysis revealed that surgical therapy was the only independent prognostic factor for survival (hazard ratio: 0.20, P=0.040). Conclusions: Resection or liver transplantation is worth considering for treatment of patients with HEH.
基金Supported by the National Science Foundation of China under Grant numbers,No.81702923Outstanding Postgraduate Seedling Cultivation Fund of Naval Medical University
文摘BACKGROUND Hepatic epithelioid angiomyolipoma(HEAML) is a rare liver disease and is easily misdiagnosed. Enhanced recognition of HEAML is beneficial to the differential diagnosis of rare liver diseases.CASE SUMMARY We presented two cases of HEAML in Changzheng Hospital, Naval Medical University, and then collected and analyzed all reports about HEAML recorded in PubMed, MEDLINE, China Science Periodical Database, and VIP database from January 2000 to March 2018. A total of 409 cases of HEAML in 97 reports were collected, with a ratio of men to women of 1:4.84 and an age range from 12 years to 80 years(median 44 years). Among the patients with clinical symptoms mentioned, 61.93%(205/331) were asymptomatic, 34.74%(115/331) showed upper or right upper quadrant abdomen discomfort, while a few of them showed abdominal mass, gastrointestinal symptoms, low fever, or weight loss. The misdiagnosis rate of HEAML was as high as 40.34%(165/409) due to its nonspecific imaging findings. Most of the tumors were solitary and round in morphology, with clear boundaries. Ultrasound scan indicated low echo with internal nonuniformity and rich blood supply in most cases. Computer tomography/magnetic resonance imaging enhanced scan showed varied characteristics. The ratio of fast wash-in and fast wash-out, fast wash-in and slow wash-out, and delayed enhancement was roughly 4:5:1. A definite diagnosis of HEAML depended on the pathological findings of the epithelioid cells in lesions and the expression of human melanoma black 45, smooth muscle actin,melanoma antigen, and actin by immunohistochemical staining. HEAML had a relatively low malignant rate of 3.91%. However, surgical resection was the main treatment for HEAML, due to the difficulty diagnosing before operation.CONCLUSION HEAML is a rare and easily misdiagnosed disease, and it should be diagnosed carefully, taking into account clinical course, imaging, pathological,and immunohistochemical findings.
文摘Perivascular epithelioid cell tumor(PEComa) is a rare mesenchymal neoplasia and currently well recognized as a distinct entity with characteristic morphological,immunohistochemical and molecular findings.We report a case of PEComa arising in the antrum of a 71-year-old female with melena.The tumor,located predominantly in the submucosa as a well delimited nodule,measured 3.0 cm in diameter and was completely resected,with no evidence of the disease elsewhere.Histologically,it was composed predominantly of eosinophilic epithelioid cells arranged in small nests commonly related to variably sized vessels,with abundant extracellular material,moderate nuclear variation and discrete mitotic activity.No necrosis,angiolymphatic invasion or perineural infil-tration was seen.Tumor cells were uniformly positive for vimentin,smooth muscle actin,desmin and melan A.Although unusual,PEComa should be considered in the differential diagnosis of gastric neoplasia with characteristic epithelioid and oncocytic features and prominent vasculature.