Short-term and long-term outcomes after robotic radical surgery for rectal gastrointestinal stromal tumor.

BACKGROUND: The optimal approach for ensuring both complete resection and preservation of anal function in rectal gastrointestinal stromal tumor (GIST) remains unknown. The aim of this study was to clarify short-term and long-term outcomes after robotic radical surgery for rectal GIST. METHODS: A total of 13 patients who underwent robotic radical surgery for rectal GIST between December 2011 and April 2022 were included. All robotic procedures were performed using a systematic approach. A supplemental video of robotic radical surgery for rectal GIST is attached. The short-term outcome was the incidence of postoperative complications during the first 30 days after surgery. Surgical outcomes were retrieved from a prospective database. Long-term outcomes, including overall survival and recurrence-free survival, were determined in all patients. RESULTS: Median distance from the tumor to the anal verge was 4.0 cm. Surgical margins were negative in all patients. Two patients underwent neoadjuvant imatinib therapy. All patients underwent sphincter-preserving surgery. None underwent conversion to open or laparoscopic surgery. The incidence of postoperative Clavien-Dindo grade II and grade ≥ III complications was 7.7% and 0%, respectively. The median postoperative hospital stay was 7 days. Twelve patients (92.3%) underwent stoma closure within 5 months of the initial surgery. Median follow-up time was 76 months. The 5-year overall survival and recurrence-free survival rates were both 100%. None of the patients had recurrence. CONCLUSION: Short-term and long-term outcomes after radical robotic surgery for rectal GIST were favorable. Robotic surgery might be a useful surgical approach for rectal GIST.

A rare clinical case of extra-gastrointestinal stromal pancreatic tumor.

Extra-gastrointestinal stromal tumors arising from the pancreas are extremely rare. To date, just over 30 cases have been described in the world literature. A clinical observation of a 67-year-old patient with dull epigastric pain and a large cystic solid neoplasm instrumentally identified as an extra-gastrointestinal stromal tumor of the head of the pancreas is presented. The volume of surgical intervention consisted of pancreatogastroduodenectomy and right-sided hemicolectomy, since tumor invasion into the transverse mesocolon was detected intraoperatively. The final diagnosis of extra-gastrointestinal stromal sarcoma of the head of the pancreas with invasion into the mesocolon pT4N0M0, stage IIIb was made on the basis of histopathology and immunohistochemistry results.

Discontinuation of imatinib in patients with oligometastatic gastrointestinal stromal tumour who are in complete radiological remission: a prospective multicentre phase II study.

INTRODUCTION: Metastatic gastrointestinal stromal tumour (GIST) is considered incurable, and life-long treatment with tyrosine kinase inhibitors is recommended. We investigated whether selected patients with metastatic GIST may remain in durable remission despite imatinib discontinuation. PATIENTS: In this 1-group, prospective, multicentre phase II trial selected patients with oligometastatic (≤3 metastases) GIST discontinued imatinib treatment. Eligible patients had been treated with imatinib >5 years without progression and had no radiologically detectable metastases after metastasectomy, radiofrequency ablation (RFA) or complete response to imatinib. The primary endpoint was progression-free survival (PFS) 3-years after stopping imatinib. Overall survival (OS) and quality of life (QoL) were secondary endpoints. RESULTS: The trial closed prematurely due to slow accrual. Between January 5, 2017, and June 5, 2019, 13 patients were enrolled, of whom 12 discontinued imatinib. The median follow-up time was 55 months (range, 36 to 69) after study entry. Five (42%) of the 12 eligible patients remained progression free, and seven (58%) progressed with a median time to progression 10 months. Median PFS was 23 months and the estimated 3-year PFS 41%. Six of the seven patients who progressed restarted imatinib, and all six responded. Three-year OS was 100%, and all patients were alive at the time of the study analysis. QoL measured 5 and 11 months after discontinuation of imatinib demonstrated improvement compared to the baseline. INTERPRETATION: A substantial proportion of selected patients with oligometastatic GIST treated with imatinib and metastasis surgery/RFA may remain disease-free for ≥3 years with improved QoL after stopping of imatinib.

Feasibility of laparoscopic and endoscopic cooperative surgery for gastric gastrointestinal stromal tumor with tumor diameter of >5 cm.

BACKGROUND: Laparoscopic and endoscopic cooperative surgery (LECS) is an effective treatment for gastric gastrointestinal stromal tumors (GISTs). The utility of LECS for gastric GISTs of > 5 cm remains controversial. This study was performed to investigate the feasibility of LECS for gastric GISTs with a tumor diameter of >5 cm. METHODS: We analyzed 43 patients with gastric GISTs who underwent LECS or laparoscopic partial gastrectomy (Lap-Partial Gx). We compared the surgical outcomes of LECS versus Lap-Partial Gx and of LECS for a tumor diameter of > 5 versus ≤ 5 cm. RESULTS: In the comparison of LECS versus Lap-Partial Gx, there were no significant intergroup differences in the operative time or blood loss volume. The morbidity rate was similar between the groups. No postoperative mortality occurred in either group. In the comparison of LECS for a tumor diameter of > 5 versus ≤ 5 cm, there were no significant intergroup differences in operative time, or blood loss volume. The morbidity rate was similar between the > 5-cm and ≤ 5-cm groups (0.0% vs. 4.5%, respectively ; p = 0.56). Additionally, no recurrence or death occurred during follow-up in either group. CONCLUSION: LECS is a feasible option for gastric GISTs with a tumor diameter of > 5 cm. J. Med. Invest. 71 : 148-153, February, 2024.

Comparable long­term survival outcomes of endoscopic treatment versus surgical treatment for gastrointestinal stromal tumors with a diameter of 5-10 cm.

Currently, endoscopic treatment for small gastrointestinal stromal tumors (GIST) has been widely accepted. However, for tumors larger than 5 cm, endoscopic treatment has not been recognized by national guidelines as the standard therapy due to concerns about safety and adverse tumor outcomes. Therefore, this study compares the long-term survival outcomes of endoscopic treatment and surgical treatment for GIST in the range of 5-10 cm. We selected patients with GIST from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. Kaplan-Meier analysis and the log-rank test were employed to compare the long-term survival outcomes between endoscopic treatment and surgical treatment. A multivariate Cox proportional hazards model was used for analysis to identify risk factors influencing patient prognosis. To balance baseline data, we performed 1:1 propensity score matching (PSM). A total of 1223 GIST patients were included, with 144 patients (11.8%) received endoscopic treatment and 1079 patients (88.2%) received surgical treatment. Before PSM, there was no significant difference in the long-term survival rates between the two groups [5-year OS (86.5% vs. 83.5%, P = 0.42), 10-year OS (70.4% vs. 66.7%, P = 0.42)]. After adjusting for covariates, we found that the overall survival (HR = 1.26, 95% CI 0.89-1.77, P = 0.19) and cancer-specific survival (HR = 1.69, 95% CI 0.99-2.89, P = 0.053) risks were comparable between the endoscopic treatment group and the surgical treatment group. In the analysis after PSM, there was no significant difference between the endoscopic treatment group and the surgical treatment group. Our study found that for GIST patients with tumor sizes between 5 and 10 cm, the long-term OS and CSS outcomes were similar between the endoscopic treatment group and the surgical treatment group.

The long-term efficacy of imatinib with hepatic resection or other local treatment for gastrointestinal stromal tumours liver metastases: a retrospective cohort study.

BACKGROUND: The liver is the most common site of metastasis from gastrointestinal stromal tumors (GISTs). The authors aimed to evaluate imatinib (IM) combined with hepatic resection (HR) or other local treatments such as radiofrequency ablation (RFA) and transarterial chemoembolization (TACE), compared to IM monotherapy in long-term survival benefits in patients suffering from GIST liver metastases. METHODS: Our research encompassed 238 patients diagnosed with liver metastases of GISTs from January 2002 to April 2022 at the First Affiliated Hospital of Sun Yat-Sen University. The oncological outcomes of concern included overall survival (OS), progression-free survival (PFS), and liver-specific PFS. RESULTS: Of all 238 patients, 126 were treated with IM alone (IM group), 81 with IM combined with HR (IM+HR group), and 31 with IM combined with RFA/TACE (IM+RFA/TACE group). The median follow-up time was 44.83 months. The median OS in the IM group was 132.60 months and was not reached in either the IM+HR group or the IM+RFA/TACE group. The 10-year OS rate in the IM+HR group was significantly superior to the IM group and the IM+RFA/TACE group (91.9% vs. 61.1% vs. 55.2%, respectively, P =0.015), and the liver-specific PFS ( P =0.642) and PFS ( P =0.369) in the three groups showed a beneficial trend in the combined treatment group. Multivariate analyses showed that age less than or equal to 60 years (HR 0.280, P< 0.001) and IM+HR (HR 0.361, P =0.047) were independently associated with better OS. Achieving no evidence of disease through surgical intervention was independently correlated with enhanced OS (HR 0.099, P =0.034), liver-specific PFS (HR 0.388, P =0.014), and PFS (HR 0.402, P =0.004). CONCLUSIONS: In patients with GIST liver metastases, IM combined with HR might improve OS in selected patients compared with IM alone and IM combined with RFA/TACE. Achieving no evidence of disease status with surgical treatment of patients results in significant prolonging of OS, liver-specific PFS, and PFS.

Jejunojejunal intussusception induced by a gastrointestinal stromal tumor: a case report and literature review.

Intussusception is defined as the invagination of a proximal segment of the bowel into the adjoining or distal segment. In most adults with intussusception, there is a demonstrable lead point with a definite pathologic abnormality. The clinical features of intussusception include chronic intermittent abdominal pain, nausea and vomiting, constipation, and a palpable abdominal mass. The present case report describes a 62-year-old woman with a 2-week history of abdominal pain and 9-day history of vomiting. Clinical, imaging, and histologic evaluations revealed a jejunojejunal intussusception with a gastrointestinal stromal tumor as the lead point. A gastrointestinal stromal tumor should be considered as a possible lead point in adult patients with intussusception. The implication of reducing the intussusception prior to tumor resection requires further evaluation in view of the risk of venous embolism, including direct spread of malignant cells, in cases involving a large polypoid mass with a necrotic surface that extends to the serosa as shown by intraoperative examination. Accordingly, the rationale for adjuvant therapy with imatinib also requires further evaluation.

[A Case of a Gastrointestinal Stromal Tumor of the Stomach with Lymph Node Metastasis].

A 87-year-old female was pointed out wall thickness in the upper part of gastric body for examination of anemia. The mass had a contrast effect, some of it protruded outside the wall, and the surrounding lymph nodes were enlarged. Upper endoscopy showed irregular ulcerative lesion with submucosal volume from posterior wall to the greater curvature in the upper part of gastric body. Biopsy was performed, and GIST of stomach was diagnosed. Surgery was performed for the GIST of the stomach. During open surgery, invasion of pancreatic tail was observed, therefore proximal gastrectomy with D1 lymph node dissection and distal pancreatectomy were performed. Pathologically, the tumor measured 95×78×65 mm with mitotic figures(38/50 high-power fields). Immunohistochemical analysis revealed that tumor cells expressed positive results for c-kit, α-SMA and CD34, and negative results for S-100 and desmin on the basis of the histology and immunostaining profile, the tumor was diagnosed as a GIST. The patient was classed as high risk according to Fletcher's risk classification. Tumor invades pancreatic tail, and lymph node metastasis was observed. She was discharged on the postoperative day 27 and alive without tumor recurrence at 6 months after surgery, not undergoing adjuvant chemotherapy.

Robot-assisted distal gastrectomy and local resection for gastric cancer and gastrointestinal stromal tumor.

Gastrointestinal stromal tumors surrounding the esophagogastric junction are often challenging to resect, with no consensus regarding the optimal surgical technique. Here in, we present a case of concurrent gastric cancer in the antrum and gastrointestinal stromal tumors adjacent to the esophagogastric junction. The patient underwent simultaneous distal gastrectomy and local resection assisted by a surgical robot, avoiding the need for total gastrectomy. The utilization of robot-assisted surgery has become an increasingly popular technique, holding promise for simplifying complex surgical procedures across diverse medical settings.

Feasibility and efficacy of minimally invasive limited resection for primary duodenal gastrointestinal stromal tumors: a retrospective cohort study.

BACKGROUND: The primary duodenal gastrointestinal stromal tumor (GIST) is a rare type of gastrointestinal tract tumor. Limited resection (LR) has been increasingly performed for duodenal GIST. However, only a few studies reported minimally invasive limited resection (MI-LR) for primary duodenal GIST. METHODS: The clinical data of 33 patients with primary duodenal GIST from December 2014 to February 2024 were retrospectively analyzed including 23 who received MI-LR and 10 who received laparoscopic or robotic pancreaticoduodenectomy (LPD/RPD). RESULTS: A total of 33 patients with primary duodenal GIST were enrolled and retrospectively reviewed. Patients received MI-LR exhibited less OT (280 vs. 388.5min, P=0.004), EBL (100 vs. 450ml, P<0.001), and lower morbidity of postoperative complications (52.2% vs. 100%, P=0.013) than LPD/RPD. Patients received LPD/RPD burdened more aggressive tumors with larger size (P=0.047), higher classification (P<0.001), and more mitotic count/50 HPF(P=0.005) compared with patients received MI-LR. The oncological outcomes were similar in MI-LR group and LPD/RPD group. All the patients underwent MI-LR with no conversion, including 12 cases of LLR and 11 cases of RLR. All of the clinicopathological data of the patients were similar in both groups. The median OT was 280(210-480) min and 257(180-450) min, and the median EBL was 100(20-1000) mL and 100(20-200) mL in the LLR and the RLR group separately. The postoperative complications mainly included DGE (LLR 4 cases, 33.4% and RLR 4 cases, 36.4%), intestinal fistula (LLR 2 cases, 16.7%, and RLR 0 case), gastrointestinal hemorrhage (LLR 0 case and RLR 1 case, 9.1%), and intra-abdominal infection (LLR 3 cases, 25.0% and RLR 1 case, 9.1%). The median postoperative length of hospitalization was 19.5(7-46) days in the LLR group and 19(9-38) days in the RLR group. No anastomotic stenosis, local recurrence or distant metastasis was observed during the follow-up period in the two groups. CONCLUSIONS: Minimally invasive limited resection is an optional treatment for primary duodenal GIST with satisfactory short-term and long-term oncological outcomes.

The correlation of sarcopenia and adverse events of imatinib therapy postoperatively in gastrointestinal stromal tumor through computed tomography quantitative body composition.

PURPOSE: This study aimed to investigate the correlation between sarcopenia and adverse events (AEs) of postoperative imatinib therapy through computed tomography (CT) quantitative body composition for intermediate- and high-risk gastrointestinal stromal tumors (GISTs). METHODS: The study retrospectively analyzed the clinical data of 208 patients with intermediate- and high-risk GIST treated surgically and treated with imatinib afterward at the First Affiliated Hospital of Wenzhou Medical University between October 2011 and October 2021. Images of preoperative CT scans within 1 month were used to determine the body composition of the patients. On the basis of the L3 skeletal muscle index, patients were classified into sarcopenia and nonsarcopenia groups. In 2 groups, AEs related to imatinib were analyzed. RESULTS: The proportion of AEs related to imatinib in the sarcopenia group was higher, and this disparity had a significant statistical significance (P = .013). Sarcopenia was significantly associated with hemoglobin reduction compared with nonsarcopenia (P = .015). There was a significant difference between the sarcopenia group and the nonsarcopenia group in the ratio of severe AEs (grades 3-4). Hemoglobin content (odds ratio [OR], 0.981; 95% CI, 0.963-1.000; P = .045), sex (OR, 0.416; 95% CI, 0.192-0.904; P = .027), and sarcopenia (OR, 5.631; 95% CI, 2.262-14.014; P < .001) were the influential factors of imatinib severe AEs in patients with intermediate- and high-risk GIST within 1 year after imatinib treatment. CONCLUSION: Patients with preoperative sarcopenia have a higher incidence and severity of AEs during adjuvant imatinib therapy.

The GIST of it all: management of gastrointestinal stromal tumors (GIST) from the first steps to tailored therapy. A bibliometric analysis.

PURPOSE: Improvement of patient care is associated with increasing publication numbers in biomedical research. However, such increasing numbers of publications make it challenging for physicians and scientists to screen and process the literature of their respective fields. In this study, we present a comprehensive bibliometric analysis of the evolution of gastrointestinal stromal tumor (GIST) research, analyzing the current state of the field and identifying key open questions going beyond the recent advantages for future studies to assess. METHODS: Using the Web of Science Core Collection, 5040 GIST-associated publications in the years 1984-2022 were identified and analyzed regarding key bibliometric variables using the Bibliometrix R package and VOSviewer software. RESULTS: GIST-associated publication numbers substantially increased over time, accentuated from year 2000 onwards, and being characterized by multinational collaborations. The main topic clusters comprise surgical management, tyrosine kinase inhibitor (TKI) development/treatment, diagnostic workup, and molecular pathophysiology. Within all main topic clusters, a significant progress is reflected by the literature over the years. This progress ranges from conventional open surgical techniques over minimally invasive, including robotic and endoscopic, resection techniques to increasing identification of specific functional genetic aberrations sensitizing for newly developed TKIs being extensively investigated in clinical studies and implemented in GIST treatment guidelines. However, especially in locally advanced, recurrent, and metastatic disease stages, surgery-related questions and certain specific questions concerning (further-line) TKI treatment resistance were infrequently addressed. CONCLUSION: Increasing GIST-related publication numbers reflect a continuous progress in the major topic clusters of the GIST research field. Especially in advanced disease stages, questions related to the interplay between surgical approaches and TKI treatment sensitivity should be addressed in future studies.

Convolutional neural network applied to preoperative venous-phase CT images predicts risk category in patients with gastric gastrointestinal stromal tumors.

OBJECTIVE: The risk category of gastric gastrointestinal stromal tumors (GISTs) are closely related to the surgical method, the scope of resection, and the need for preoperative chemotherapy. We aimed to develop and validate convolutional neural network (CNN) models based on preoperative venous-phase CT images to predict the risk category of gastric GISTs. METHOD: A total of 425 patients pathologically diagnosed with gastric GISTs at the authors' medical centers between January 2012 and July 2021 were split into a training set (154, 84, and 59 with very low/low, intermediate, and high-risk, respectively) and a validation set (67, 35, and 26, respectively). Three CNN models were constructed by obtaining the upper and lower 1, 4, and 7 layers of the maximum tumour mask slice based on venous-phase CT Images and models of CNN_layer3, CNN_layer9, and CNN_layer15 established, respectively. The area under the receiver operating characteristics curve (AUROC) and the Obuchowski index were calculated to compare the diagnostic performance of the CNN models. RESULTS: In the validation set, CNN_layer3, CNN_layer9, and CNN_layer15 had AUROCs of 0.89, 0.90, and 0.90, respectively, for low-risk gastric GISTs; 0.82, 0.83, and 0.83 for intermediate-risk gastric GISTs; and 0.86, 0.86, and 0.85 for high-risk gastric GISTs. In the validation dataset, CNN_layer3 (Obuchowski index, 0.871) provided similar performance than CNN_layer9 and CNN_layer15 (Obuchowski index, 0.875 and 0.873, respectively) in prediction of the gastric GIST risk category (All P >.05). CONCLUSIONS: The CNN based on preoperative venous-phase CT images showed good performance for predicting the risk category of gastric GISTs.

Clinical characteristics and prognostic analysis of postoperative recurrence or metastasis of low-risk gastrointestinal stromal tumors.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract. This study aimed to investigate the clinical characteristics and prognosis of postoperative recurrence or metastasis in patients with low-risk stromal tumors, in order to take individualized postoperative management and treatment for patients with low-risk GISTs with relatively high recurrence. METHODS: We retrospectively analyzed the clinicopathological and follow-up data of patients with GISTs who underwent surgical resection in Nanjing Drum Tower Hospital from March 2010 to December 2021. A total of 282 patients with low-risk GISTs were included, none of whom were treated with imatinib. Univariate and multivariate Cox analysis and survival curves were used to explore the relationship between clinical features and recurrence or metastasis in patients with low-risk GISTs. RESULTS: Of the 282 patients with low-risk GISTs who met inclusion criteria, 14 (4.96%) had recurrence or metastasis. There was a correlation between tumor size, primary site, resection type, Ki67 index, neutrophil lymphocyte ratio (NLR) and CD34 expression and postoperative recurrence or metastasis of GISTs (P < 0.05). Subsequently, multifactorial analysis showed that tumor primary site, tumor size, and Ki67 index were independent risk factors affecting postoperative recurrent or metastasis in patients with low-risk GISTs (P < 0.05). Ultimately, According to Kaplan-Meier analysis, non-gastric primary tumors, larger tumors, and high Ki67 index were significantly associated with poor progression-free survival ( PFS ). CONCLUSIONS: Tumor location, tumor size and Ki-67 were independent risk factors for postoperative recurrence and metastasis in patients with low-risk GISTs. Based on the 2008 modified NIH recurrence risk grading system, combined with the above three factors, it can be used to evaluate the prognosis of patients with low-risk GISTs and provide personalized postoperative review and follow-up management recommendations.

Transumbilical Endoscopic Resection of Intra-abdominal Mesenchymal Tumor.

Gastrointestinal stromal tumors (GISTs) typically occur in the stomach and proximal small intestine but can also be found in any other part of the digestive tract, including the abdominal cavity, albeit rarely. In the present case, the tumor was resected endoscopically through the anterior gastric wall. Computed tomography (CT) scan and gastroscopy of a 60-year-old woman revealed submucosal lesions in the gastric body. The possibility of a stromal tumor was considered more likely. The endoscopic surgery was performed under endotracheal anesthesia. After a solution had been injected at the lesion site in the stomach, the entire gastric wall was dissected to expose the tumor. As the lesion was in the abdominal cavity and its base was attached to the abdominal wall, it was accessed using a sterilized PCF colonoscope. A sodium chloride injection was administered at the base. The tumor was then peeled along its boundaries using the hooking and excision knife combined with the precutting knife. Subsequently, the tumor was pulled into the stomach through the incision made in the stomach and then extracted externally through the upper digestive tract using the ERCP spiral mesh basket. After confirming the absence of bleeding at the incision site, the endoscope was returned to the stomach, and the stomach opening was closed using purse-string sutures. The patient recovered satisfactorily following the surgery and was discharged on day 4. Histological examination revealed a low-risk stromal tumor (spindle cell type, <5 mitosis/50 high-power fields [HPF]). Immunohistochemistry revealed positive staining for CD34 and CD117, negative staining for SMA, positive staining for DOG1, and negative staining for S100. Additionally, the expression of ki67 was 3%.

Colonic gastrointestinal stromal tumor (GIST) presenting with colocolonic intussusception: A rare case report.

An 8-year-old spayed female British bulldog was presented with vomiting, hyporexia, and large-bowel diarrhea. Abdominal ultrasound revealed a focal colonic mass with an intussusception located immediately oral to the mass. The intussusception encompassed the ascending and transverse colon and was non-reducible. Colonic resection and anastomosis were completed to include the intussusception and colonic mass. Histopathological examination of the mass demonstrated a spindle cell neoplasm arising within the muscular wall of the intussuscepted segment that obliterated normal architecture. Mild-to-moderate cytoplasmic immunoreactivity of the tumor cell population for CD117 and smooth muscle actin was consistent with a diagnosis of a gastrointestinal stromal tumor. The dog described herein remains alive and free of progressive disease at the time of writing. Key clinical message: The entire gastrointestinal tract should be evaluated in any animal with gastrointestinal symptoms. A gastrointestinal stromal tumor remains a plausible differential diagnosis, regardless of the intestinal segment affected, and tumorassociated intussusception is a rare but urgent clinical finding.

Tumeur stromale gastro-intestinale du côlon (GIST) présentant une invagination colocolique : un rapport de cas rare. Une femelle bouledogue anglais stérilisée de 8 ans a présenté des vomissements, une hyporexie et une diarrhée d'origine du gros intestin. L'échographie abdominale a révélé une masse colique focale avec une invagination située immédiatement oralement à la masse. L'intussusception englobait le côlon ascendant et transverse et était non réductible. La résection colique et l'anastomose ont été réalisées pour inclure l'intussusception et la masse colique. L'examen histopathologique de la masse a révélé un néoplasme à cellules fusiformes apparaissant dans la paroi musculaire du segment invaginé qui a oblitéré l'architecture normale. L'immunoréactivité cytoplasmique légère à modérée de la population de cellules tumorales pour le CD117 et l'actine des muscles lisses étaient compatibles avec un diagnostic de tumeur stromale gastro-intestinale. Le chien décrit ici est toujours vivant et exempt de maladie évolutive au moment de la rédaction.Message clinique clé :L'ensemble du tractus gastro-intestinal doit être évalué chez tout animal présentant des symptômes gastrointestinaux. Une tumeur stromale gastro-intestinale reste un diagnostic différentiel plausible, quel que soit le segment intestinal atteint, et l'intussusception associée à la tumeur est une constatation clinique rare mais urgente.(Traduit par Dr Serge Messier).

[Reappraisals of biological behaviors of PDGFRA mutant gastrointestinal stromal tumor].

Objective: To investigate the biological behavior spectrum of platelet-derived growth factor alpha receptor (PDGFRA)-mutant gastrointestinal stromal tumor (GIST), and to compare the clinical values of the Zhongshan method of benign and malignant evaluation with the modified National Institutes of Health (NIH) risk stratification. Methods: A total of 119 cases of GIST with PDGFRA mutation who underwent surgical resection at Zhongshan Hospital, Fudan University from 2009 to 2020 were collected. The clinicopathological data, follow-up records, and subsequent treatment were reviewed and analyzed statistically. Results: There were 79 males and 40 females. The patients ranged in age from 25 to 80 years, with a median age of 60 years. Among them, 115 patients were followed up for 1-154 months, and 13 patients progressed to disease. The 5-year disease-free survival (DFS) and overall survival (OS) were 90.1% and 94.1%, respectively. According to the modified NIH risk stratification, 8 cases, 32 cases, 38 cases, and 35 cases were very-low risk, low risk, intermediate risk, and high risk, and 5-year DFS were 100.0%, 95.6%, 94.3%, and 80.5%, respectively. There was no significant difference in prognosis among the non-high risk groups, only the difference between high risk and non-high risk groups was significant (P=0.029). However, the 5-year OS was 100.0%, 100.0%, 95.0% and 89.0%, and there was no difference (P=0.221). According to the benign and malignant evaluation Zhongshan method, 43 cases were non-malignant (37.4%), 56 cases were low-grade malignant (48.7%), 9 cases were moderately malignant (7.8%), and 7 cases were highly malignant (6.1%). The 5-year DFS were 100.0%, 91.7%, 77.8%, 38.1%, and the difference was significant (P<0.001). The 5-year OS were 100.0%, 97.5%, 77.8%, 66.7%, the difference was significant (P<0.001). Conclusions: GIST with PDGFRA gene mutation shows a broad range of biological behavior, ranging from benign to highly malignant. According to the Zhongshan method, non-malignant and low-grade malignant tumors are common, the prognosis after surgery is good, while the fewer medium-high malignant tumors showed poor prognosis after surgical resection. The overall biological behavior of this type of GIST is relatively inert, which is due to the low proportion of medium-high malignant GIST. The modified NIH risk stratification may not be effective in risk stratification for PDGFRA mutant GIST.