Hepatic inflammatory myofibroblastic tumor: A case report

BACKGROUND Hepatic inflammatory myofibroblastic tumor(HIMT)is a rare type of hepatic tumor.It is always misdiagnosed and mistreated because it is primarily found with no obvious specific manifestation,and its imaging findings are diverse.CASE SUMMARY Here,we report a case of HIMT that was initially diagnosed as liver malignancy but was confirmed as HIMT by histopathology after hepatectomy.Mostly,HIMTs are infiltrated with plasma cells and stain positively for anaplastic lymphoma kinase on immunohistochemistry as well as for some other kinases.CONCLUSION HIMT can be treated with single nonsteroidal anti-inflammatory drugs and without surgery when it is diagnosed accurately.Because the etiology of HIMT is unknown and the diagnosis is difficult,the pathogenesis and clinical process need to be further studied.

Inflammatory myofibroblastic tumor of the pancreatic neck misdiagnosed as neuroendocrine tumor:A case report

BACKGROUND Inflammatory myofibroblastic tumor(IMT)is a relatively rare tumor.The global incidence of IMT is less than 1%.There is no specific clinical manifestation.It usually occurs in the lungs,but the pancreas is not the predilection site.CASE SUMMARY We present a case of a male patient,51 years old,who was diagnosed with a pancreatic neck small mass on ultrasound one year ago during a physical examination.As he had no clinical symptoms and the mass was relatively small,he did not undergo treatment.However,the mass was found to be larger on review,and he was referred to our hospital.Since the primal clinical diagnosis was pancreatic neuroendocrine tumor,the patient underwent surgical treatment.However,the case was confirmed as pancreatic IMT by postoperative pathology.CONCLUSION Pancreatic IMT is relatively rare and easily misdiagnosed.We can better understand and correctly diagnose this disease by this case report.

Gastric inflammatory myofibroblastic tumor, a rare mesenchymalneoplasm: A case report

BACKGROUND The inflammatory myofibroblastic tumor(IMT)is a rare mesenquimal tumor of doubtful biological behaviour.It’s characterised for affecting mainly children and young adults,although it can appear at any age,being the lungs the primary affected organ(in children it represents 20%of all primary pulmonary tumors).CASE SUMMARY We present the case of a 45 year old woman,with a computed tomography(CT)finding of injury on the anterior surface of the fundus/gastric body and a solid perigastric injury of 12 mm in the ecoendoscopy.The case is presented in the tumor committee deciding to perform a laparoscopic wedge resection.The histological diagnosis was a IMT.The diagnosis is based on imaging tests like the abdominal CT,abdominal ecography and the ecoendoscopy but to confirm the diagnosis a pathological study is necessary.CONCLUSION Due to the unpredictable nature of this tumor,surgical resection is the best therapeutic option.

Inflammatory myofibroblastic tumor of the distal common bile duct:Literature review with focus on pathological examination

Inflammatory myofibroblastic tumor(IMT)of the biliary tract is rare,and often difficult to diagnose or to distinguish from other tumors due to its atypical clinical presentation and nonspecific radiological features.Histologically,IMTs are(myo)fibroblastic neoplasms with a prominent inflammatory infiltrate.They are characterized by receptor tyrosine kinase gene rearrangements,most often involving an anaplastic lymphoma kinase(ALK)translocation.The final diagnosis of IMT depends on histopathology and immunohistochemical examination.In this manuscript,we provide a clinical and morphomolecular overview of IMT and the difficulties that may arise in using immunohistochemical and molecular techniques in diagnosing IMT.

Huge pelvi-abdominal malignant inflammatory myofibroblastic tumor with rapid recurrence in a 14-year-old boy

Inflammatory myofibroblastic tumor(IMT) is an uncommon benign neoplasm with locally aggressive behavior but malignant change is rare.We report an unusual case of pelvic-abdominal inflammatory myofibroblastic tumor with malignant transformation in a 14-year-old boy presenting with abdominal pain and 9 kg body weight loss in one month.Computed tomography revealed a huge pelvi-abdominal mass(30 cm),possibly originating from the pelvic extraperitoneal space,protruding into the abdomen leading to upward displacement of the bowel loops,downward displacement of the urinary bladder,massive central necrosis,a well-enhanced peripheral solid component with prominent peritumoral vascularity.Subsequent examination confirmed the computed tomographic findings.Histopathologic examination revealed proliferative epitheloid and spindle cells,inflammatory cell infiltration and high mitotic counts.Immunohistochemistry was strongly positive for anaplastic lymphoma kinase and revealed a high proliferative index(ki-67 = 40%).DNA sequencing and electronic microscopy further confirmed the primitive fibroblastic cell phenotype of the tumor and a final diagnosis of inflammatory myofibroblastic tumor with malignant transformation was established.Rapid tumor recurrence was noted 20 d after radical tumor resection.To our knowledge,this is the largest documented case of IMT in a pediatric patient and the first report of IMT with malignant transformation originating from the pelvic extraperitoneal space.

Inflammatory myofibroblastic tumor successfully treated with chemotherapy and nonsteroidals:A case report

Inflammatory myofibroblastic tumor(IMT) occurring at retroperitoneal sites has rarely been reported.We report the case of a previously well 14-year-old girl with no history of abdominal disease whose past medical history and family tumor history were unremarkable.She complained of intermittent abdominal pain for one month.An abdominal mass was found on physical examination and abdominal contrast-enhanced computed tomography(CT) showed a hypodense soft mass,the size and location of which suggested a well delineated retroperitoneal tumor surrounding the superior mesenteric vessels measuring 3.3 cm × 4.5 cm × 4.5 cm with enlarged lymph nodes.The patient underwent an exploratory laparotomy followed by biopsy and was subsequently diagnosed with retroperitoneal IMT.She was successfully treated with postoperative chemotherapy and oral diclofenac sodium.Following completion of therapy the mass was no longer palpable and no longer visible on CT scanning.The use of methotrexate and cisplatin for aggressive myofibroblastic tumors is also reviewed.

Intra-abdominal inflammatory myofibroblastic tumor:Spontaneous regression

Inflammatory myofibroblastic tumors are usually treated by surgical resection. We herein report two cases of intra-abdominal inflammatory myofibroblastic tumors that were unresectable and underwent spontaneous regression without any treatment. Our case report and literature review show that regression is more common in the middle-aged and older male populations. Abdominal discomfort and fever were the most common symptoms, but the majority of patients had no obvious physical signs. There was no specific indicator for diagnosis. The majority of the lesions regressed within3 mo and nearly all of the masses completely resolved within 1 year. We conclude that the clinical characteristics of inflammatory myofibroblastic tumors are variable and, accordingly, the disease needs to be subdivided and treated on an individual basis. Surgery is always the first-line treatment; however, for those masses assessed as unresectable, conservative therapy with in-tense follow-up should be considered.

Different imaging findings of inflammatory myofibroblastic tumor of the liver

Inflammatory myofibroblastic tumor(IMT) in the liver is an uncommon lesion of uncertain pathogenesis.In most cases,symptomatological imaging and clinical studies suggest malignancy.We report a case of liver IMT with imaging findings from positron emission tomography/computed tomography(PET/CT),contrastenhanced computed tomography(CECT) and contrastenhanced ultrasonography(CEUS).This report was the first to depict a PET/CT scan of a liver IMT that revealed an inhomogeneous,intense(fluorine 18)-fluoro-2-deoxy-D-glucose uptake.The CECT and CEUS images showed a hepatic artery supplying blood to the mass and necrosis.The characteristic histopathological features and the presence of spindle cells expressing smooth muscle actin,collagen fibers and lymphocytes allowed for the diagnosis of liver IMT.Recognizing such findings will help to achieve a correct diagnosis and may prevent inappropriate treatment.

Plexiform angiomyxoid myofibroblastic tumor treated by endoscopic submucosal dissection:A case report and review of the literature

BACKGROUND Plexiform angiomyxoid myofibroblastic tumor(PAMT)is a rare mesenchymal tumor characterized by multiple nodular plexiform growth patterns and an immunophenotype with myofibroblasts.The pathological characteristics,immunohistochemistry,diagnostic criteria,differential diagnosis,and gene-level changes of PAMT have been reported in many studies.At present,the main treatment for PAMT in the reported cases is surgery;only eight cases were treated via endoscopy(excluding 1 thoracoscopic resection),and the lesions were all smaller than 5 cm.There are no reports on the prognosis and follow-up of young patients with lesion sizes reaching 5 cm who undergo endoscopic submucosal dissection(ESD).Herein,we present the first case of a young patient with a lesion size reaching 5 cm who was diagnosed with PAMT via endoscopic submucosal dissection.CASE SUMMARY A 15-year-old young man with upper abdominal pain for 2 years presented to the Gastroenterology Department of our hospital.Painless gastroscopy showed a semicircular bulge approximately 5 cm in size in the lesser curvature near the cardia of the fundus;the surface was eroded,and shallow ulcers had formed.The pathological manifestations of the biopsy were spindle cell proliferative lesions with interstitial mucinous changes,and the surface mucosa showed chronic inflammatory changes with active lesions;immunohistochemistry showed smooth muscle actin(SMA)(+),CD117(-),CD34(-),DOG-1(-),S-100(-),and Ki67(LI:<1%).We performed ESD on the patient.The lesion that we removed was 5 cm×4 cm×2 cm in size.Pathologically,the resected tissue displayed typical manifestations,such as fat spindle-shaped fibroblasts and myofibroblast-like cells showing irregular nodular hyperplasia.Immunohistochemistry staining of the tumor cells revealed the following:CD34(partially+),SMA(weakly+),CD117(-),DOG-1(-),S-100(-),SDHB(+),PCK(-),and Ki67(labelling index:2%).There was no recurrence or metastasis during the 3-mo follow-up after the operation,and the treatment effect was good.We also performed a review of the literature on the clinical manifestations,pathological features,immunohistochemistry,and differential diagnosis of PAMT.CONCLUSION At present,the diagnostic criteria for PAMT are relatively clear,but the pathogenesis and genetic changes require further study.PAMT is benign in nature,and these patients are less likely to experience local or metastatic recurrence.The main treatment is still surgery if the lesion is in the stomach.Partial gastrectomy and distal gastrectomy are the most frequently performed surgical treatments for PAMT,followed by local resection,subtotal gastrectomy,and wedge resection.But for comprehensive evaluation of the disease,ESD can be considered a suitable method to avoid excessive treatment.

Kidney inflammatory myofibroblastic tumor masquerading as metastatic malignancy: A case report and literature review

BACKGROUND Inflammatory myofibroblastic tumor(IMT) is a rare mesenchymal tumor that is characterized by spindle cells differentiated from muscle fibroblasts and infiltration of various types of inflammatory cells. IMT can occur at any age and at any anatomic site. The most common location of IMT is the bladder in the genitourinary tract. Only scarce cases of kidney IMT have been reported in the literature.CASE SUMMARY A 77-year-old woman, with a history of bilateral renal calculus for 15 years, was admitted to the Department of Urology of our hospital complaining of recurrent painless gross hematuria for one month. The treatment with cephalosporin was ineffective. Computed tomography imaging showed a mixed density and slightly heterogeneously enhanced lesion in the middle pole of the left kidney and ipsilateral adrenal enlargement. The patient underwent surgical treatment by retroperitoneoscopic left radical nephrectomy plus adrenalectomy. A large number of typical spindle cells surrounded by plasma cells and lymphocytes were observed microscopically. Immunohistochemical analyses indicated that these spindle cells were positive for vimentin, cytokeratin(CK), Ki-67, CK7,CD34, and CD31 and were focally positive for CD10 and anaplastic lymphoma kinase(ALK-1). Thus, a diagnosis of IMT was made definitively. The patient recovered well after operation, and no recurrence or metastasis was noted during the 22-mo follow-up.CONCLUSION Since kidney IMT is very rare and lacks characteristic clinical manifestation, it is easily misdiagnosed as a malignant tumor before operation. Surgery remains the best choice for diagnosis and treatment, and such cases must be followed carefully because of the uncertain biological behavior of this tumor. This report suggests that renal calculus may be one of the causes of IMT, but further investigation is necessary to prove it.

Infant biliary cirrhosis secondary to a biliary inflammatory myofibroblastic tumor: A case report and review of literature

BACKGROUND A biliary inflammatory myofibroblastic tumor(IMT)is a rare type of mesenchymoma that,although it has a broad age spectrum,usually occurs in adults.Diagnosis is difficult because biliary IMTs often exhibit nonspecific clinical symptoms and imaging features,resulting in delayed or inappropriate treatment.Although most IMTs are benign,some show malignant properties such as infiltration,recurrence,and metastasis.CASE SUMMARY Here,we retrospectively describe a 10-month-old infant who was admitted to our hospital due to stubborn jaundice.The patient responded poorly to routine medical treatment and his clinical manifestations and laboratory tests lacked specificity,so we turned to repeated ultrasound scans and other imaging examinations.As both hepatosplenic ultrasonography and diffusion-weighted magnetic resonance imaging demonstrated a space-occupying lesion,an exploratory laparotomy was performed.The final diagnosis made over two mo after the disease onset was infant biliary cirrhosis caused by a biliary IMT,which partially infiltrated into the liver.This infant is the youngest case of biliary IMTs that has been reported till now.The patient underwent an incomplete resection of the mass and Kasai Portoenterostomy.However,because of cirrhosis,he also received a paternal liver transplant.Since some IMTs show malignant properties,we proceeded with a three-year of follow-up;however,no recurrence or metastasis has been noted.CONCLUSION Neoplastic disease such as IMTs should be considered when routine medical treatment of obstructive jaundice is not successful.Observation of dynamic imaging changes is helpful for diagnosis.Periodic follow-up is necessary for IMTs.

Inflammatory myofibroblastic tumor of the pancreatic neck:A case report and review of literature

BACKGROUND Pancreatic inflammatory myofibroblastic tumor(IMT)is a relatively rare disease that is often confused with pancreatic cancer or pancreatic neuroendocrine tumors.The histological features of IMTs show that tissue from this type of tumor contains an intermingling of fibroblast and myofibroblast proliferation,accompanied by a varying degree of inflammatory cell infiltration.CASE SUMMARY The management of an IMT occurring at the neck of the pancreas is presented in this paper.A 66-year-old female patient was diagnosed with a pancreatic neck mass after a series of tests.The patient underwent enucleation of the pancreatic neck tumor after a pathological diagnosis of IMT.Previous research on the clinical features,pathological diagnosis and treatment of pancreatic IMTs was reviewed.Compared with previous reports,this is a unique case of enucleation of a pancreatic IMT.CONCLUSION The enucleation of pancreatic IMTs may be a safe and efficient surgical method for managing such tumors with a better prognosis.Further cases are required to explore surgical measures for pancreatic IMTs.

Agressive inflammatory myofibroblastic tumor of the liver with underlying schistosomiasis:A case report

Inflammatory myofibroblastic tumor(IMT)occurs infrequently in the liver.It is controversial whether it represents a low grade mesenchymal neoplasm or a reactive inflammatory lesion.Local recurrence and metastasis are rare and some tumors are associated with infectious agents.We report on a case of a large and partially resected IMT with local recurrence and diaphragm and kidney infiltration detected on routine surveillance two years later.Histologically,the tumor showed spindle cells without atypia,mitosis or necrotic areas in a myxoid and collagenized background with inflammatory cells.In the liver portal tracts,granulomatous lesions with viable eggs of Schistosoma mansoni were identified.Immunohistochemistry demonstrated spindle cells which were smooth-muscle actin and vimentin positive.In conclusion,this case points out that these histological patterns do not predict the aggressive biological behavior of the lesion.A reason for the recurrence and the infiltration may be incomplete tumor resection.Further investigation is necessary in order to better clarify an infectious cause in some IMTs.

Inflammatory myofibroblastic tumor after breast prosthesis:A case report and literature review

BACKGROUND Inflammatory myofibroblastic tumors(IMTs)are defined as tumors composed of differentiated myofibroblastic spindle cells,usually accompanied by numerous plasma cells and lymphocytes,and classified as intermediate(occasionally metastatic)by the World Health Organization.Its pathogenesis and biological behavior have not yet been elucidated.Breast IMT is extremely rare,and prosthesis implantation combined with IMT has not been reported.This study reports a case of IMT following resection of a malignant phyllodes tumor of the left breast and implantation of a prosthesis.CASE SUMMARY A 41-year-old female presented to our hospital with a mass in the left breast for 3 mo.The patient had undergone resection of a large mass in her left breast pathologically diagnosed as a malignant phyllodes tumor and implantation of a prosthesis five years prior.Ultrasonic examination revealed an oval mass in the left breast,and the patient underwent left breast mass resection and prosthesis removal.Light microscopy revealed the spindle cells to be diffusely proliferated,with a large number of neutrophils,lymphocytes,and plasma cell infiltration.Immunohistochemical staining revealed that the spindle cells were partially positive for smooth muscle actin,which is positive for BCL-2 and cluster of differentiation(CD)99 but were negative for anaplastic lymphoma kinase,cytokeratin,S-100 protein,desmin,and CD34.The final diagnosis was IMT.No recurrence or metastasis was observed during the 5-year postoperative follow-up.CONCLUSION Prosthesis implantation may be one of the causes of IMT,but further investigation is necessary to prove it.

Inflammatory Myofibroblastic Tumor Mimicking Malignant Meningioma in the Middle Cranial Fossa:a Case Report

INFLAMMATORY myofibroblastic tumor（IMT）,alsoknown as inflammatory pseudotumor or plasma cellgranulomas,is an uncommon fibro-inflammatorylesion which is composed of inflammatory cells andmyofibroblastic spindle cells.1Its pathogenesis is still un-known.The tumor commonly occurs in the lung,upperrespiratory tract,live,orbit,abdominal membrane,retro-peritoneum,and genitourinary tract.2-4It rarely involvesthe central nerve system,5,

Inflammatory myofibroblastic tumor successfully treated with metformin: A case report and review of literature

BACKGROUND Inflammatory myofibroblastic tumor(IMT)is a distinct tumor with a low incidence rate,which can be diagnosed at any age with a predilection for children and adolescents.Although IMT is visible in any tissues and organs,it is more commonly found in the lungs.The clinical and radiological manifestations of IMT lack specificity,hence resulting in frequent misdiagnosis.Surgical resection is currently the main therapeutic approach for IMT.Only scarce cases of IMT treated with metformin have been reported.Here we report the case of an IMT patient with partial penile resection treated with metformin.CASE SUMMARY A 1-year-old boy was born with a shorter penis,and his foreskin could not be completely turned over.When he was 6 month old,a well-circumscribed mass on the glans was found,while it did not attract the attention of his parents.The mass gradually increased in size over time before he was admitted to the hospital,where physical examination was performed.It was revealed that the glans hidden behind the foreskin had a mass with a diameter of about 4 cm surrounding the penis.The mass appeared to be hard with a smooth surface and poor mobility.The two testicles examined at the bottom of the scrotum were revealed to have a normal size.Magnetic resonance imaging showed a tumor with rich blood supply encircling the cavernosum with a size of 3.5 cm×2.1 cm×2.0 cm.A thick urinary line was found without urine dripping,urgency,and urodynia.Surgical treatment was performed.During the operation,it was observed that the mass had surrounded and invaded the cavernosum without obvious boundaries,and that the tumor occupied about one-half of the penis cross-section as well as infiltrated more than one-half of the glans.In addition,the tumor had caused urethral invasion and anterior urethrostenosis.With the intention of keeping the glans and cavernosum,the tumor at the anterior urethra was partially removed,leaving about 30%of the tumor mass.Pathology analysis demonstrated that the tumor was rich in spindle cells with infiltration of inflammatory cells.Immunohistochemistry analysis indicated that the cells were positive for CD4,CD99,Ki67,BCL2,and CD68,and negative for ALK,MyoG,S100,SOX10,PR,and EMA.Hence,the tumor was diagnosed as IMT.Metformin was prescribed for the patient after the operation,following which an oral dose of 7 mg/kg was given three times a day after meals.Three months later,it was observed that the remaining tumor had completely disappeared and that the urination process from the urethra opening had resumed normal.In addition,there were no side effects observed.There was also no tumor recurrence.The growth and development of the boy were unaffected as a result of the treatment.CONCLUSION The tumor was observed to have completely disappeared after treatment with metformin.Our finding is of great significance to facilitate future clinical treatment with IMT.

Complicated course of biliary inflammatory myofibroblastic tumor mimicking hilar cholangiocarcinoma:A case report and literature review

BACKGROUND The inflammatory myofibroblastic tumor(IMT)is a rare,idiopathic,usually benign,mass-forming disease with myofibroblastic proliferation and a varying amount of inflammatory cells.Although it can affect various organs,the biliary tract is a rare localization of primary IMT,clinically,endoscopically and radiologically imitating cholangiocarcinoma.The treatment options are based only on clinical practice experience.CASE SUMMARY A 70-year-old woman was referred to our center due to progressive fatigue,weight loss,abdominal pain,night sweats,and elevated liver enzymes.Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography(ERCP)revealed proximal common hepatic duct and hilar biliary strictures extending bilaterally to lobular bile ducts.Although initial clinical,endoscopic and radiological signs were typical for hilar cholangiocarcinoma,histological examination showed no signs of malignancy.In total,8 biopsies using different approaches were performed(several biopsies from dominant stricture during ERCP and direct cholangioscopy;ultrasound-guided liver biopsy;diagnostic laparoscopy with liver and lymph node biopsies).Histological examination revealed signs of IMT,and the final diagnosis of biliary IMT was stated.Although IMT is usually a benign disease,in our case,it was complicated.All pharmacological treatment measures were ineffective.The patient still needs permanent stenting,suffers from recurrent infections and mechanical jaundice.Despite that,the patient already survived 24 mo.CONCLUSION IMT presenting with hilar biliary strictures is a unique diagnostic and clinical challenge as it is indistinguishable from cholangiocarcinoma,and there are no evidence-based treatment options.Our goal is to increase the understanding of this rare disease and its possible course.

Laparoscopic treatment of inflammatory myofibroblastic tumor in liver: A case report

BACKGROUND Inflammatory myofibroblastic tumor in the liver(IMTL) is a rare borderline mesenchymal tumor.Neither clinical symptoms nor laboratory tests have absolute specificity for the diagnosis of IMTL,and imaging also lacks obvious specificity.Although there are sporadic reports of recurrence after surgical treatment,surgical resection is the mainstay of treatment.CASE SUMMARY A 29-year-old man complained of general weakness,slight discomfort in the upper abdomen,with a history of upper respiratory tract infection for 1 wk before admission.Plain and enhanced upper abdominal magnetic resonance imaging showed a mass in liver segments Ⅱ and Ⅲ(48 mm × 53 mm).He was treated by laparoscopic left lateral segmentectomy.Postoperative pathological examination with hematoxylin and eosin staining suggested that the mass in liver segments Ⅱ and Ⅲ was IMTL.During 21 mo postoperative follow-up,no obvious residual or recurrent lesions were observed.CONCLUSION There is a risk of malignant degeneration in IMTL.The principal choice of treatment is laparoscopic left lateral segmentectomy.

Inflammatory myofibroblastic tumor of the central nervous system:A case report

BACKGROUND An inflammatory myofibroblastic tumor(IMT)occurring in the central nervous system is very rare,and thus its pathogenesis is unknown.This case report and literature review aimed to explore the pathogenesis,clinical features,imaging findings,pathological characteristics,immunohistochemical characteristics,diagnoses,treatments,and risks of postoperative recurrence of IMT in the central nervous system.CASE SUMMARY A 67-year-old woman was admitted to the hospital with an exophthalmic protrusion and double vision in the left eye that had persisted for 3 mo.Magnetic resonance imaging(MRI)showed a 2.4 cm×1.3 cm heterogeneous large mass in the bottom of the left anterior cranial fossa,which was closely related to the dura mater.Before surgery,we suspected the mass to be meningioma.The entire mass was successfully removed under neuronavigation and electrophysiological monitoring,and postoperative pathology indicated an IMT with extensive infiltration of chronic inflammatory cells and scattered multinucleated giant cells.Head MRI at the 3-mo follow-up showed that the tumor at the bottom of left anterior cranial fossa had been completely resected without recurrence.CONCLUSION From the histological,immunohistochemical,and genetic analyses,the present case suggests that the pathogenesis of IMT-CNS is related to autoimmunity.

Radiotherapy for Lowly Malignant Cranial Inflammatory Myofibroblastic Tumor Accompanied with Intracranial Invasion:Case Report and Literature Review

Inflammatory myofibroblastic tumor(IMT) is rare in clinical practice.As its treatment mainly involves surgery,radiotherapy alone is seldom reported in literature.Here we report a case of lowly malignant cranial IMT with intracranial invasion in a female patient. As surgery was not suitable,intensity modulated radiation therapy(IMRT) was administered.After radiotherapy,the cranial lesions tended to show efficacy.