Impact of tumour rupture risk on the oncological rationale for the surgical treatment choice of gastrointestinal stromal tumours

Tumour rupture of gastrointestinal stromal tumours(GISTs)has been considered to be a remarkable risk factor because of its unfavourable impact on the oncological outcome.Although tumour rupture has not yet been included in the current tumor-node-metastasis classification of GISTs as a prognostic factor,it may change the natural history of a low-risk GIST to a high-risk GIST.Originally,tumour rupture was defined as the spillage or fracture of a tumour into a body cavity,but recently,new definitions have been proposed.These definitions distinguished from the prognostic point of view between the major defects of tumour integrity,which are considered tumour rupture,and the minor defects of tumour integrity,which are not considered tumour rupture.Moreover,it has been demonstrated that the risk of disease recurrence in R1 patients is largely modulated by the presence of tumour rupture.Therefore,after excluding tumour rupture,R1 may not be an unfavourable prognostic factor for GISTs.Additionally,after the standard adjuvant treatment of imatinib for GIST with rupture,a high recurrence rate persists.This review highlights the prognostic value of tumour rupture in GISTs and emphasizes the need to carefully take into account and minimize the risk of tumour rupture when choosing surgical strategies for GISTs.

Multidisciplinary diagnosis and treatment nutritional support intervention for gastrointestinal tumor radiotherapy:Impact on nutrition and quality of life

BACKGROUND Gastrointestinal tumors are a major cause of cancer-related deaths and have become a major public health problem.This study aims to provide a scientific basis for improving clinical treatment effects,quality of life,and prognosis of patients with gastrointestinal tumors.AIM To explore the clinical effect of the multidisciplinary diagnosis and treatment(MDT)nutrition intervention model on patients with gastrointestinal tumors.METHODS This was a case control study which included patients with gastrointestinal tumors who received radiotherapy at the Department of Oncology between January 2021 and January 2023.Using a random number table,120 patients were randomly divided into MDT and control groups with 60 patients in each group.To analyze the effect of MDT on the nutritional status and quality of life of the patients,the nutritional status and quality of life scores of the patients were measured before and after the treatment.RESULTS Albumin(ALB),transferrin(TRF),hemoglobin(Hb),and total protein(TP)levels significantly decreased after the treatment.The control group had significantly lower ALB,TRF,Hb,and TP levels than the MDT group,and the differences in these levels between the two groups were statistically significant(P<0.05).After the treatment,the MDT group had significantly more wellnourished patients than the control group(P<0.05).The quality of life total score,somatic functioning,role functioning,and emotional functioning were higher in the MDT group than in the control group.By contrast,pain,fatigue,nausea,and vomiting scores were lower in the MDT group than in the control group(P<0.05).CONCLUSION MDT nutritional intervention model effectively improves the nutritional status and quality of life of the patients.The study provides a rigorous theoretical basis for improving the prognosis of cancer patients.In the future,we intend to provide additional treatment methods for improving the quality of life of patients with cancer.

Prevalence, diagnosis, and treatment of primary hepatic gastrointestinal stromal tumors

Gastrointestinal stromal tumors(GIST), which is the most common mesenchymal tumor of the digestive tract, account for 1%-3% of gastrointestinal tumors. Primary stromal tumors outside the gastrointestinal tract are collectively referred to as extra GISTs, and stromal tumors in different regions often have different prognoses. A primary hepatic GIST is a rare tumor with an unknown origin, which may be related to interstitial Cajal-like cells. Although primary hepatic GIST has certain characteristics on imaging, it lacks specific symptoms and signs;thus, the final diagnosis depends on pathological and genetic evidence. This review summarizes all cases of primary hepatic GIST described in the literature and comprehensively analyzes the detailed clinical data of all patients. In terms of treatment, local resection alone or with adjuvant therapy was the prioritized choice to obtain better disease-free survival and longer survival time. For advanced unresectable cases, imatinib mesylate was applied as the first-line chemotherapy agent. Moreover, transcatheter arterial chemoembolization,/by-nc/4.0/Manuscript source: Unsolicited manuscript radiofrequency ablation, and microwave ablation were shown to improve overall survival for selected patients. Liver transplantation was a final treatment option after resistance to chemotherapy developed.

Comprehensive evaluation of rare case:From diagnosis to treatment of a sigmoid Schwannoma:A case report

BACKGROUND Schwannomas are uncommon tumors originating from Schwann cells,forming the neural sheath.They account for approximately 2%-6%of all mesenchymal tumors and are most commonly identified in peripheral nerve trunks,with rarity in the gastrointestinal tract.Among gastrointestinal locations,the stomach harbors the majority of nerve sheath tumors,while such occurrences in the sigmoid colon are exceptionally infrequent.CASE SUMMARY This study presented a clinical case involving a 60-year-old female patient who,during colonoscopy,was diagnosed with a submucosal lesion that was later identified as a nerve sheath tumor.The patient underwent surgical resection,and the diagnosis was confirmed through immunohistochemistry.This study highlighted an exceptionally uncommon occurrence of a nerve sheath tumor in the sigmoid colon,which was effectively managed within our department.Additionally,a comprehensive review of relevant studies was conducted.CONCLUSION The preoperative diagnosis of nerve sheath tumors poses challenges,as the definitive diagnosis still relies on pathology and immunohistochemistry.Although categorized as benign,these tumors have the potential to demonstrate malignant behavior.Consequently,the optimal treatment approach entails the complete surgical excision of the tumor,ensuring the absence of residual lesions at the margins.

Synchronous occurrence of gastric cancer and gastrointestinal stromal tumor: A case report and review of the literature

BACKGROUND To evaluate the clinicopathological features and prognosis of gastric cancer(GC)occurring synchronously with gastrointestinal stromal tumor(GIST).CASE SUMMARY We report 19 patients with concurrent GC and GIST(17 male and 2 female,median age 62 years).GC was most often located in the lower third of the stomach.GIST was diagnosed preoperatively in four patients.GIST was most often located in the gastric body(n=8,42%).The most common growth pattern in GIST was extraluminal(n=12,63%).The positive expression rates of CD117 and CD34 in GIST were 100% and 95%,respectively.Most patients with GIST(n=17,89%)were very low or low risk.There was no recurrence of GIST during follow-up.The 3-year cumulative survival rate was 73.9%,and the 5-year cumulative survival rate was 59.2%.The combined analysis of this study and literature reports(47 reports,157 patients)found that GC and GIST were usually located in the lower third(42%)and middle third(51%)of the stomach.GC was usually early(stage I:42%),poorly differentiated(42%)intestinal-type adenocarcinoma(51%).GISTs were primarily small in diameter(median:1.2 cm)and very low or low risk(89%).CONCLUSION Synchronous GC and GIST may not be rare.They have specific clinicopathological characteristics,and may have mutual inhibition in pathogenesis and progression.

Examining the impact of early enteral nutritional support on postoperative recovery in patients undergoing surgical treatment for gastrointestinal neoplasms

BACKGROUND Patients with gastrointestinal tumors often suffer from poor nutritional status during treatment.Surgery is the main treatment for these patients,but the long postoperative recovery period is often accompanied by digestive and absorption dysfunction,leading to further deterioration of the nutritional status.Early enteral nutrition support is hypothesized to be helpful in improving this situation,but the exact effects have yet to be studied in depth.AIM To observe the effect of early enteral nutritional support on postoperative recovery in patients with surgically treated gastrointestinal tract tumors,with the expectation that by improving the nutritional status of patients,the recovery process would be accelerated and the incidence of complications would be reduced,thus improving the quality of life.METHODS A retrospective analysis of 121 patients with gastrointestinal tract tumors treated in our hospital from January 2020 to January 2023 was performed.Fifty-three of these patients received complete parenteral nutrition support as the control group for this study.The other 68 patients received early enteral nutritional support as the observation group of this study.The clinical indicators comparing the two groups included time to fever,time to recovery of postoperative bowel function,time to postoperative exhaustion,and length of hospital stay.The changes in immune function and nutritional indexes in the two groups were compared.Furthermore,we utilized the SF-36 scale to compare the changes in the quality of life between the two groups of patients.Finally,the occurrence of postoperative complications between the two patient groups was also compared.RESULTS The postoperative fever time,postoperative bowel function recovery time,postoperative exhaustion time,and hospitalization time were all higher in the control group than in the observation group(P<0.05).The levels of CD3+,CD4+,immunoglobulin(Ig)A,IgM,and IgG in the observation group were significantly higher than those in the control group at 1 d and 7 d postoperatively,while CD8+was lower than in the control group(P<0.05).Total protein,albumin,prealbumin,and transferrin levels were significantly higher in the observation group than in the control group at 7 d postoperatively(P<0.05).The SF-36 scores of patients in the observation group were significantly higher than those in the control group(P<0.0001).The overall incidence of adverse reactions after the intervention was significantly lower in the control group than in the observation group(P=0.021).CONCLUSION We found that patients with gastrointestinal tumors are nutritionally vulnerable,and early enteral nutrition support programs can improve the nutritional status of patients and speed up postoperative recovery.This program can not only improve the immune function of the patient and protect the intestinal function,but it can also help to improve the quality of life of the patient.However,this program will increase the incidence of complications in patients.Caution should be taken when adopting early enteral nutrition support measures for patients with gastric cancer.The patient's condition and physical condition should be comprehensively evaluated and closely monitored to prevent possible complications.

Chinese consensus guidelines for diagnosis and management of gastrointestinal stromal tumor

In order to further promote the standardization of diagnosis and treatment of gastrointestinal stromal tumor （GIST） in China, the members of Chinese Society of Clinical Oncology （CSCO） Expert Committee on GIST thoroughly discussed the key contents of the consensus guidelines, and voted on the controversial issue. In final, the Chinese consensus guidelines for the diagnosis and management of GIST （2017 edition） was formed on the basis of 2013 edition consensus guidelines, which is hereby announced. The consensus included the pathological diagnosis, recurrence risk classification evaluation, targeted agent therapy, surgery and principles of surveillance of GIST.

Current clinical management of gastrointestinal stromal tumor

Gastrointestinal stromal tumors(GISTs) are the most common malignant subepithelial lesions(SELs) of the gastrointestinal tract. They originate from the interstitial cells of Cajal located within the muscle layer and are characterized by over-expression of the tyrosine kinase receptor KIT. Pathologically, diagnosis of a GIST relies on morphology and immunohistochemistry [KIT and/or discovered on gastrointestinal stromal tumor 1(DOG1) is generally positive]. The prognosis of this disease is associated with the tumor size and mitotic index. The standard treatment of a GIST without metastasis is surgical resection. A GIST with metastasis is usually only treated by tyrosine kinase inhibitors without radical cure; thus, early diagnosis is the only way to improve its prognosis. However, a GIST is usually detected as a SEL during endoscopy, and many benign and malignant conditions may manifest as SELs. Conventional endoscopic biopsy is difficult for tumors without ulceration. Most SELs have therefore been managed without a histological diagnosis. However, a favorable prognosis of a GIST is associated with early histological diagnosis and R0 resection. Endoscopic ultrasonography(EUS) and EUS-guided fine needle aspiration(EUSFNA) are critical for an accurate diagnosis of SELs. EUSFNA is safe and effective in enabling an early histological diagnosis and adequate treatment. This review outlines the current evidence for the diagnosis and management of GISTs, with an emphasis on early management of small SELs.

Esophagogastric junction gastrointestinal stromal tumor:Resection vs enucleation

Esophageal gastrointestinal stromal tumors(GISTs) are extremely uncommon,representing approximately 5% of GISTs with the majority of esophageal GISTs occurring at the esophagogastric junction(EGJ).The treatment options available for these GISTs are fairly controversial.Many different options are nowadays at our disposal.From surgery to the target therapies we have the possibility to treat the majority of GISTs,including those which are defined as unresectable.The EGJ GISTs represent a stimulating challenge for the surgeon.The anatomical location increases the possibility of postoperative complications.As the role of negative margins in GIST surgery is still controversial and the eff icacy of target therapy has been demonstrated,why not treat EGJ GISTs with enucleation and,where indicated,adjuvant target therapy?

GASTROINTESTINAL STROMAL TUMORS OF THE ANORECTUM——A SPECIAL ENTITY: GISTs OF THE ANORECTUM

Objective： Until recently gastrointestinal stromal tumor （GIST） has been separated from other mesenchymal neoplasms and categorized as a special entity. Morphology of tumor cells and immunohistochemical findings with CD117 are crucial in the pathological diagnosis of GISTs. Newly developed drug imatinib mesylate （formerly called STI571） has been proved effective for GISTs. The distinction of GISTs and other mesenchymal tumors has great clinical significance, especially for lesions located in the anorectum. Methods： The authors searched the database of Peking University, School of Ontology for patients with anorectal neoplasms treated from January 1995 to June 2002. Information of 12 patients with anorectal mesenchymal tumors was collected. The patients were reevaluated and discussed according to current criteria of GISTs with clinical data and immunohistochemical findings. Results： Six patients （including 3 males） were finally diagnosed as anorectal GISTs. The median age of those patients was 59.5 years （27～69）. The symptoms were not specific. Three cases with original diagnosis of leiomyoma or leiomyosarcoma were actually GISTs. A total of six anorectal GISTs was found comprising about 1.06% of patients with anorectal neoplasmas in the same period. Besides CD117, CD34 and vimentin were also expressed in majority of these patients. Five of the six patients underwent surgical resection one of which received neoadjuvant chemotherapy before resection Conclusion： Anorectal GISTs should be considered as a special entity using current diagnostic criteria. Surgical resection remains the primary therapeutic strategy. Neoadjuvant imatinib mesylate may be helpful in sphincter-sparing operations and improvement of the quality of life for these patients.

Expression profile of microRNAs in gastrointestinal stromal tumors revealed by high throughput quantitative RT-PCR microarray

AIM: To investigate the microRNA(miRNA) expression profile in gastrointestinal stromal tumor(GIST) tissues that could serve as a novel diagnostic biomarker for GIST detection.METHODS: We performed a quantitative real-time quantitative reverse transcriptase polymerase chain reaction assay to analyze the expression of 1888 miRNAs in a sample set that included 54 GIST tissue samples.RESULTS: We found that dysregulation of several miRNAs may be related to the malignant potential of GISTs. Six of these miRNAs, hsa-let-7c, miR-218,miR-488#, miR-4683, miR-34c-5p and miR-4773, were selected as the final list of biomarkers to separate the malignant GISTs(M group) from the benign GISTs(B group). In addition, MiR-29b-2#, hsa-let-7c, miR-891 b, miR-218, miR-204, miR-204-3p, miR-628-5p,miR-744, miR-29c#, miR-625 and miR-196 a were used to distinguish between the borderline(BO group) and M groups. There were 11 common miRNAs selected to separate the benign and borderline(BB) group from the M group, including hsa-let-7c, miR-218, miR-628-5p,miR-204-3p, miR-204, miR-891 b, miR-488#, miR-145,miR-891 a, miR-34c-5p and miR-196 a.CONCLUSION: The identified miRNAs appear tobe novel biomarkers to distinguish malignant from benign GISTs, which may be helpful to understand the mechanisms of GIST oncogenesis and progression,and to further elucidate the characteristics of GIST subtypes.

Comparison between air and carbon dioxide insufflation in the endoscopic submucosal excavation of gastrointestinal stromal tumors

AIM:To evaluate the safety and efficacy of CO2 insufflation compared with air insufflation in the endoscopic submucosal excavation(ESE) of gastrointestinal stromal tumors.METHODS:Sixty patients were randomized to undergo endoscopic submucosal excavation,with the CO2 group(n = 30) and the air group(n = 30) undergoingCO2 insufflation and air insufflation in the ESE,respectively.The end-tidal CO2 level(pETCO2) was observed at 4 time points:at the beginning of ESE,at total removal of the tumors,at completed wound management,and 10 min after ESE.Additionally,the patients' experience of pain at 1,3,6 and 24 h after the examination was registered using a visual analog scale(VAS).RESULTS:Both the CO2 group and air group were similar in mean age,sex,body mass index(all P > 0.05).There were no significant differences in PetCO2 values before and after the procedure(P > 0.05).However,the pain scores after the ESE at different time points in the CO2 group decreased significantly compared with the air group(1 h:21.2 ± 3.4 vs 61.5 ± 1.7;3 h:8.5 ± 0.7 vs 42.9 ± 1.3;6 h:4.4 ± 1.6 vs 27.6 ± 1.2;24 h:2.3 ± 0.4 vs 21.4 ± 0.7,P < 0.05).Meanwhile,the percentage of VAS scores of 0 in the CO2 group after 1,3,6 and 24 h was significantly higher than that in the air group(60.7 ± 1.4 vs 18.9 ± 1.5,81.5 ± 2.3 vs 20.6 ± 1.2,89.2 ± 0.7 vs 36.8 ± 0.9,91.3 ± 0.8 vs 63.8 ± 1.3,respectively,P < 0.05).Moreover,the condition of the CO2 group was better than that of the air group with respect to anal exsufflation.CONCLUSION:Insufflation of CO2 in the ESE of gastrointestinal stromal tumors will not cause CO2 retention and it may significantly reduce the level of pain,thus it is safe and effective.

Efficacy and safety of endoscopic resection in treatment of small gastric stromal tumors: A state-of-the-art review

Gastrointestinal stromal tumors can occur in any part of the gastrointestinal tract,but gastric stromal tumors(GSTs)are the most common.All GSTs have the potential to become malignant,and these can be divided into four different grades by risk from low to high:Very low risk,low risk,medium risk,and high risk.Current guidelines all recommend early complete excision of GSTs larger than 2 cm in diameter.However,it is not clear whether small GSTs(sGSTs,i.e.,those smaller than 2 cm in diameter)should be treated as early as possible.The National Comprehensive Cancer Network recommends that endoscopic ultrasonographyguided(EUS-guided)fine-needle aspiration biopsy and imaging(computed tomography or magnetic-resonance imaging)be used to assess cancer risk for sGSTs detected by gastroscopy to determine treatment.When EUS indicates a higher risk of tumor,surgical resection is recommended.There are some questions on whether sGSTs also require early treatment.Many studies have shown that endoscopic treatment of GSTs with diameters of 2-5 cm is very effective.We here address whether endoscopic therapy is also suitable for sGSTs.In this paper,we try to explain three questions:(1)Does sGST require treatment?(2)Is digestive endoscopy a safe and effective means of treating sGST?and(3)When sGSTs are at different sites and depths,which endoscopic treatment method is more suitable?

Efficacy of endoscopic ultrasound in the evaluation of small gastrointestinal stromal tumors

BACKGROUND Gastrointestinal stromal tumors(GISTs)with a diameter of<2 cm are called small GISTs.Currently,endoscopic ultrasound(EUS)is widely used as a regular followup method for GISTs,which can also provide a preliminary basis for judging the malignancy potential of lesions.However,there are no studies on the accuracy of EUS to assess the malignant potential of small GISTs.AIM To evaluate the efficacy of EUS in the diagnosis and risk assessment of small GISTs.METHODS We collected data from patients with small GISTs who were admitted to Shengjing Hospital of China Medical University between October 2014 and July 2019.The accurate diagnosis and risk classifications of patients were based on the pathological assessment according to the modified National Institute of Health criteria after endoscopic resection or laparoscopic surgery.Preoperative EUS features(marginal irregularity,cystic changes,homogeneity,ulceration,and strong echogenic foci)were retrospectively analyzed.The assessment results based on EUS features were compared with the pathological features.RESULTS A total of 256 patients(69 men and 187 women)were enrolled.Pathological results included 232,16,7,and 1 very low-,low-,intermediate-,and high-risk cases,respectively.The most frequent tumor location was the gastric fundus(78.1%),and mitoses were calculated as>5/50 high power field in 8(3.1%)patients.Marginal irregularity,ulceration,strong echo foci,and heterogeneity were detected in 1(0.4%),2(0.8%),22(8.6%),and 67(65.1%)patients,respectively.However,cystic changes were not detected.Tumor size was positively correlated with the mitotic index(P<0.001).Receiver operating curve analysis identified 1.48 cm as the best cut-off value to predict malignant potential(95%confidence interval:0.824–0.956).EUS heterogeneity with tumor diameters>1.48 cm was associated with higher risk classification(P<0.05).CONCLUSION Small GISTs(diameters>1.48 cm)with positive EUS features should receive intensive surveillance or undergo endoscopic surgery.EUS and dissection are efficient diagnostic and therapeutic approaches for small GISTs.

Effectiveness and safety of endoscopic resection for duodenal gastrointestinal stromal tumors:A single center analysis

BACKGROUND Endoscopic resection for duodenal gastrointestinal stromal tumors(GISTs)is still considered a great challenge with a high risk of complications,including perforation,bleeding,tumor rupture,and residual tumor.AIM To assess the effectiveness and safety of endoscopic resection for duodenal GISTs.METHODS Between January 2010 and January 2022,11 patients with duodenal GISTs were treated with endoscopic resection.Data were extracted for the incidence of complete resection,bleeding,perforation,postoperative infection,recurrence,and distant metastasis.RESULTS The incidence of successful complete resection of duodenal GISTs was 100%.Three cases(27.3%)had suspected positive margins,and the other 8 cases(72.7%)had negative vertical and horizontal margins.Perforation occurred in all 11 patients.The success rate of perforation closure was 100%,while 1 patient(9.1%)had suspected delayed perforation.All bleeding during the procedure was managed by endoscopic methods.One case(9.1%)had delayed bleeding.Postoperative infection occurred in 6 patients(54.5%),including 1 who developed septic shock and 1 who developed a right iliac fossa abscess.All 11 patients recovered and were discharged.The mean hospital stay was 15.3 d.During the follow-up period(14-80 mo),duodenal stenosis occurred in 1 case(9.1%),and no local recurrence or distant metastasis were detected.CONCLUSION Endoscopic resection for duodenal GISTs appears to be an effective and safe minimally invasive treatment when performed by an experienced endoscopist.

Intra-abdominal desmoid tumors mimicking gastrointestinal stromal tumors——8 cases: A case report

BACKGROUND Intra-abdominal desmoid tumors(DTs) can mimic recurrence or progression of gastrointestinal stromal tumors(GISTs). Differential diagnosis is important to avoid unnecessary or inappropriate treatment.CASE SUMMARY All 8 patients experienced surgical resection of GIST, and median time to diagnosis of DT was 1.8 years after surgical resection. All sites of DT were in the peritoneum around the surgical sites of GIST. The following clinical suspicion coupled with radiological findings contributed to the suspicion of intraabdominal DTs:(1) Occurrence of a new single lesion in the peritoneum around the surgical sites of GIST;(2) uncontrolled lesion with imatinib while other lesions being controlled with imatinib;(3) well-defined ovoid shaped lesion with delayed or mild enhancement and absence of necrosis, hemorrhage, and cystic change on computed tomography; and(4) a lesion showing mild or no hypermetabolic activity on 18 fluorodeoxyglucose-positron emission tomography,contrary to initially hyperactive lesion of GIST. All DTs were surgically removed except for one unresectable DT and only one DT recurred at another site of peritoneum, which was also surgically removed.CONCLUSION Intra-abdominal DT should be a differential diagnosis for a new single lesion in patients with GIST.

Primary gastrointestinal stromal tumor of the liver treated with sequential therapy

A 67-year-old female presented with a primary hepatic gastrointestinal stromal tumor that was detected by computed tomography and diagnosed based on histopathological and genetic analyses.The tumor was microscopically composed of spindle cells and epithelioid cells,and immunohistochemistry results showed positive staining for CD117 and CD34expression.A genetic analysis revealed a heterozygous point mutation and deletion in exon 11 of c-KIT.After an R0 resection,imatinib mesylate was administered for 1 year until its use was discontinued due to severe side effects.Two years after the original operation,the tumor recurred in the residual liver and was completely resected again.Imatinib mesylate was administered for 2 years until it was replaced by sunitinib malate because of disease progression.The patient has survived for 53 mo after undergoing a sequential therapy consisting of surgical excision,imatinib and sunitinib.

Characterizing gastrointestinal stromal tumors and evaluating neoadjuvant imatinib by sequencing of endoscopic ultrasound-biopsies

AIM To evaluate endoscopic ultrasound(EUS)-guided biopsies for the pretreatment characterization of gastrointestinal stromal tumors(GIST) to personalize the management of patients.METHODS All patients with lesions suspected to be GIST who were referred for EUS-sampling at a tertiary Swedish center were eligible for inclusion 2006-2015. During the observational study phase(2006-2011), routine fine-needle-aspiration(EUS-FNA) was performed.In 2012-2015, we converted to an interventional, randomized protocol with dual sampling EUS-FNA and fine-needle-biopsy-sampling(EUS-FNB) for all lesions. c-KIT-and DOG-1-immunostaining was attempted in all samples and a manual count of the Ki-67-index was performed. FNB-sampled tissue and the resected specimens were subjected to Sanger sequencing of the KIT and platelet-derived growth factor alpha(PDGFRA) genes. RESULTS In all, 64 unique patients with GIST were included, and of these, 38 were subjected to pretreatment dual sampling. EUS-FNB had a higher diagnostic sensitivity when compared head-to-head with EUS-FNA(98% vs 58%, P < 0.001) and was more adequate for Ki-67-indexing(Ki-67EUS)(92% vs 40%, P < 0.001). Sequencing of EUS-biopsies was successful in 43/44(98%) patients, and the mutation profiles(KIT-mutation 73%, PDGFRA-mutation 18%, wild-type 7%) were fully congruent with those detected in the corresponding resected specimens. In imatinib-na?ve patients, the Ki-67_(EUS) was comparable with the Ki-67-index in the corresponding surgical specimens(Ki-67_(SURG))(2.7% vs 2.9%, P = 0.68). In patients treated with neoadjuvant imatinib who also carried mutations indicating sensitivity, the Ki-67 EUS was higher than the Ki-67_(SURG)(2.5% vs 0.2%, P = 0.005), with a significant reduction in the Ki-67-index of-91.5%(95%CI:-82.4 to-96.0, P = 0.005). CONCLUSION EUS-guided biopsy sampling is accurate for the pretreatment diagnosis and characterization of GISTs and allows the prediction and evaluation of tumor response to neoadjuvant imatinib therapy.

REFLECTIONS ON SURGICAL TREATMENT OF 214 CASES OF PRIMARY MEDIASTINAL TUMOR

Our hospital documented 214 cases of primary mediastinal tumor from May 1957 to July 1995. They were treated surgically, There were 184 benign cases (85. 98% ), and 30 malignant cases (14.02 % ). Among them, there were 63 cases of neurogenic tumor (29.43 % ), 48 cases of thymic tumor (22. 4% ), 41 cases of teratoid tumor (19. 16% ), 12 cases of bronchial cyst (5. 61% ), and 9cases of intrathoracic adenoma of thyroid (4. 21%). The authors mainiy discuss the early diagnosis,tumor variety, operating incisions, and operating essentials.