Resection Of Gastrointestinal Stromal Tumors Research Articles

Reduced-port surgery aided by the newly developed free jaw clip and free loop plus for local resection of gastric submucosal tumors

Background: Gastric cancer requiring lymph node dissection is not often approached laparoscopically because of the surgical difficulty. However, in cases of gastric submucosal tumor, such as gastroin-testinal stromal tumor (GIST), lymph node dissection is not usually necessary. Local resection is generally sufficient, and GIST, then, is a good indication for reduced-port surgery (RPS). We describe RPS performed through two ports—one in the umbilicus and one in the left epigastric region. Two devices have been developed for this procedure: the free jaw (FJ) clip, which is used to grasp organs in the abdominal cavity, and the free loop plus, which is used pull suture threads from inside the abdominal cavity to outside the body. We have used the new devices with good outcomes in 11 patients undergoing resection of GIST. We describe the new devices, their use in RPS for GIST, and the case outcomes. Methods: The FJ clip is a short clip designed to assist with organ elevation. The clip comes in two sizes, one for use in a 5-mm port and the other for use in a 12-mm port, and in two lengths, 29.4 and 35.6 mm, respectively. Both clips are made of stainless steel, and they can be easily maneuvered with commonly-used laparoscopy forceps. The clips have a powerful grasping force (200±20 and 300±30 gf, respectively) but cause no or only negligible organ damage. The jaw surface is textured in a lattice-like relief to resist slippage. The free loop plus is used to puncture the abdominal wall and pull suture threads from inside the abdominal cavity to outside the body. It is fitted with a φ 0.1-mm NiTi alloy suture thread that passes through a 90-mm 21 G stainless steel needle. Generally, the device is attached to the FJ clip and used to guide the traction suture to outside the body. Results: In the 11 cases noted above, mean operation time was 156 minutes (78–287 minutes). The blood loss volume was ≤30 g per patient and so low in 8 patients that it could not be measured. In all 11 patients, the surgery was performed via two ports, one in the umbilicus and the other in the left epigastric region. Laparoscopic endoscopic cooperative surgery was performed in 4 of the 11 patients. There were no intraoperative or postoperative complications, and the mean postoperative hospital stay was 9.9 days (range, 8–11 days). Conclusions: Our success with the devices leads us to believe that the FJ clip will assume the role of forceps in many laparoscopic surgery settings in fields such as obstetrics and gynecology and urology. We are also led to believe that the FJ clip will pave the way for new developments in RPS.

Laparoscopic Resection of Gastrointestinal Stromal Tumors at the Duodenojejunal Junction

Abstract Introduction: Segmental resection of gastrointestinal stromal tumors (GISTs) at the duodenojejunal junction is technically challenging, and most cases are performed through an open techniq...

Appropriate Follow-Up Strategies for Gastrointestinal Stromal Tumor Patients Based on the Analysis of Recurrent Interval and Patterns

Background/Aims: Previous studies have proposed risk classifications for patients with gastrointestinal stromal tumor (GIST) after resection and have contributed to the prediction of its prognosis. However, optimal postoperative surveillance has not yet been established. Methods: We retrospectively analyzed data from 115 GIST patients who experienced recurrence after complete resection. The relationships between clinicopathological characteristics and the first recurrence sites, or time to recurrence (TTR), were investigated. We also compared the characteristics between 2 subgroups based on a TTR of ≤5 or >5 years. Results: The first recurrence occurred in the abdomen in 114 of 115 patients (99.1%); one case of esophageal GIST recurred in the lung. Gastric and small intestinal GISTs recurred most frequently in the liver or peritoneum, while the most common recurrences of colorectal GISTs were found to be local. Fourteen patients (12.2%) experienced recurrence after >5 years. Smaller tumors and those categorized as lower risk were significantly more frequent in the TTR >5 years group than in the TTR ≤5 years group. In the TTR >5 years group, local recurrence was the most frequent type of recurrence (42.9%). Conclusion: Based on abdominal examination, postoperative surveillance after complete resection for primary GISTs may be recommended for >5 years.

Incorporation of NLR into NIH stratification system increases predictive accuracy for surgically resected gastrointestinal stromal tumors.

Previous studies have reported that preoperative neutrophil-to-lymphocyte (NLR) and platelet-to-lymphocyte ratios were prognostic for various types of cancers. The aim of this study was to investigate the predictive utilities of preoperative peripheral blood counts in patients with gastrointestinal stromal tumors (GISTs). We enrolled 510 consecutive, previously untreated patients who underwent surgery for primary, localized GISTs. The relationship between recurrence-free survival and outcome variables was assessed by univariate and multivariate analyses, while the clinicopathologic relevance of NLR was determined using the Chi-square test. A preoperative NLR ≥2 was associated with poor prognosis in patients undergoing surgeries for primary, localized GISTs. It was an independent predictor only in patients classified asNational Institutes of Health high risk but not in the entire population. Preoperative NLR is a feasible and reproducible peripheral biomarker that helps identify patients for intensive adjuvant therapy and frequent surveillance.

Application value of nomogram and risk factors of postoperative recurrence of gastrointestinal stromal tumors

Objective To investigate the risk factors of postoperative recurrence of gastrointestinal stromal tumors (GISTs) and verify the clinical value of nomogram of the Memorial Sloan Kettering Cancer Center (MSKCC), and draw a new nomogram model and a calibration curve. Methods The retrospective case-control study was conducted. The clinical data of 90 patients with GISTs who were admitted to the Affiliated Cancer Hospital of Shanxi Medical University between June 2000 and January 2009 were collected. All the patients underwent radical resection of GISTs and didn′t take oral imatinib mesylate of postoperative adjunctive therapy. The clinicopathological data of patients were used for prognostic analysis. Postoperative GISTs of patients were predicted by nomogram of the MSKCC. Area under ROC curves was calculated through the comparison between probability of new samples from Bootstrop and real probability of recurrence of patients. A new nomogram model and calibration curve were built using the R language. Observation indicators: (1) real recurrence situations of GISTs; (2) risk factors analysis affecting the postoperative recurrence of GISTs; (3) a nomogram of MSKCC predicting the postoperative theoretical recurrence situations of GISTs in each patient; (4) establishment of the new nomogram model and calibration curve. The follow-up using telephone interview, outpatient examination and visit was performed to detect the postoperative recurrence of GISTs up to February 2016. The survival curve was drawn by the Kaplan-Meier method. The univariate analysis and multivariate analysis were done respectively using the chi-sqaure test and COX regression model. A risk model of postoperative recurrence of GISTs was built. The new nomogram model and calibration curve of postoperative recurrence-free survival rate were drawn according to the regression coefficients and other data of selected variables in the COX regression model. Results (1) Real recurrence situations of GISTs: all the 90 patients were followed up for 1-82 months, with a median time of 25 months. The 2-, 5-year recurrence-free survival rates were respectively 52.2%(47/90)and 11.1%(10/90). (2) Risk factors analysis affecting the postoperative recurrence of GISTs: results of univariate analysis showed that age, CD117, tumor location, tumor diameter and mitotic figures were risk factors affecting the postoperative recurrence of GISTs (χ2=9.276, 19.911, 31.721, 32.973, 6.482, P<0.05). Results of multivariate analysis showed that non-gastrointestinal tumor, tumor diameter≥10 cm and mitotic figures≥5/50 high power field (HPF) were independent risk factors affecting the postoperative recurrence of GISTs [RR=1.166, 5.905, 1.012, 95% confidence interval (CI): 1.004-1.355, 2.076-16.796, 1.008-1.017, P<0.05]. (3) A nomogram of MSKCC predicting the postoperative theoretical recurrence situations of GISTs in each patient: the area under the curve (AUC) of 2-, 5-year recurrence-free survival rates in a nomogram of MSKCC was respectively 0.727 (95%CI: 0.662-0.791) and 0.724 (95%CI: 0.658-0.791). (4) Establishment of the new nomogram model and calibration curve: the new nomogram model and calibration curve were build using R language. The alignment pattern was close to a straight line with slope 1, and a nomogram can accurately predict the postoperative recurrence risk of GISTs. The AUC in the nomogram model was 0.724 (95%CI: 0.629-0.783), and a modified and standard AUC of the National Institutes of Health (NIH) was 0.434 (95%CI: 0.347-0.521). Conclusion The non-gastrointestinal tumor, tumor diameter≥10 cm and mitotic figures≥5/50 HPF are independent risk factors affecting the postoperative recurrence of GISTs, and the nomogram can assess the postoperative recurrence risk of GISTs. Key words: Gastrointestinal stromal tumors; Nomogram; Recurrence; Risk assessment

Preoperative Chemotherapy and Survival for Large Anorectal Gastrointestinal Stromal Tumors: A National Analysis of 333 Cases.

Anorectal gastrointestinal stromal tumors (GISTs) are exceedingly rare, and management remains controversial in regard to local resection (LR) and preoperative chemotherapy. The National Cancer Data Base was queried from 1998 to 2012 for cases of GIST resection in the rectum or anus. Patient demographics, type of surgery (LR vs. radical excision [RE]), short-term outcomes, and overall survival (OS) were analyzed. Preoperative chemotherapy was recorded following the US FDA approval of imatinib in 2002. Overall, 333 patients with resection of anorectal GISTs were included. Mean age at presentation was 62.3years (range 22-90), and median tumor size was 4.0cm (interquartile range 2.2-7.0). Five-year OS for all patients was 77.6%. In a multivariable survival analysis, only age and tumor size >5cm (hazard ratio 2.48, 95% confidence interval 1.50-4.01; p=0.004) were associated with increased mortality. One hundred and sixty-three (49.0%) patients underwent LR, compared with 158 (47.4%) who underwent RE. For tumors smaller than 5cm, no difference in 5-year survival by surgical approach was observed (LR 82.3% vs. RE 82.6%; p=0.71). Fifty-nine patients (17.7%) received preoperative chemotherapy; for patients undergoing RE with tumors >5cm, there was decreased mortality in the group who received preoperative chemotherapy (5-year OS with chemotherapy 79.2% vs. no chemotherapy 51.2%; p=0.03). Size is the most important determinant in survival following resection. Local excision is common, with resection split between LR and RE. For smaller tumors, LR may be adequate therapy. Preoperative chemotherapy may result in improved survival for large tumors treated with radical resection, but the data are imperfect.

Laparoscopic resection of duodenal gastrointestinal stromal tumour.

Only a few studies have revealed using laparoscopic technique with limited resection of gastrointestinal stromal tumour (GIST) of the duodenum. A 68-year-old man was admitted to the hospital due to upper gastrointestinal (GI) bleeding. Evaluation revealed an ulcerated, bleeding GI tumour in the second part of the duodenum. After control of bleeding during gastroduodenoscopy, he underwent a laparoscopic wedge resection of the area. During 1.5 years of follow-up, the patient is disease free, eats drinks well, and has regained weight. Surgical resection of duodenal GIST with free margins is the main treatment of this tumour. Various surgical treatment options have been reported. Laparoscopic resection of duodenal GIST is an advanced and challenging procedure requiring experience and good surgical technique. The laparoscopic limited resection of duodenal GIST is feasible and safe, reducing postoperative morbidity without compromising oncologic results.

Outcome of surgical resection for localized gastrointestinal stromal tumors

Background:Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. The clinical outcome and the factors which are potentially related to tumor recurrence and survival after surgical intervention for GISTs has not been adequately addressed in the Southern part of Egypt.Methods: Medical records of adult patients who underwent surgical resection of localized GISTs (February 2007 - December 2013) in Sohag University Hospital were reviewed. Data on the clinical presentation, treatment strategies, tumor characteristics including the risk for aggressive behavior and survival rate were analyzed.Results:Fifteen patients with 7 gastric (47%), 5 small bowel (33%), 2 duodenal (13%) and 1 colonic (7%) GISTs and median age of 56 (range: 32-73) years were eligible. Nine patients (60%) were males. Non-specific abdominal pain was the most common presenting symptoms (40%). Emergency presentation occurred only in two patients (13%). Complete resection was achieved in thirteen patients (87%). There was no major operative morbidity or mortality. The risk for aggressive behaviour was low in 7 (47%), intermediate in 5 (33%) and high in 3 (20%) patients. Two patients died 7 and 10 months after surgery, one with histopathological criteria of high risk for aggressive tumor behaviour and the other with incomplete tumor resection. During a median follow up of 21 (range: 8 - 48) months, overall and recurrence-free survival were 87% and 67%, respectively.Conclusions:Adequate resection of GISTs is associated with high rate of survival. Increased risk for aggressive tumor behaviour and incomplete resection are associated with tumor recurrence and decreased survival.

Analysis of safety and efficacy of laparoscopic resection for gastrointestinal stromal tumors of the stomach and little bowel: Review of literature

Gastrointestinal stromal tumors (GISTs) are rare tumors representing 0.1%–3% of all gastrointestinal cancers with an estimated incidence of 15/million. These tumors are characterized by the overexpression of the tyrosine kinase receptor KIT (CD117). The diagnosis of GIST has dramatically increased since 1992, and survival has greatly improved since 2002 when the Food and Drug Administration approved imatinib mesylate. Surgical treatment is the only chance of cure for patients with primary localized GIST. There is no surgical consensus about laparoscopic or open surgical treatment. However, the role for laparoscopy in the resection of GISTs continues to expand. The laparoscopic approach for gastric GISTs offers significant advantages in terms of postoperative pain, surgical trauma, and hospitalization, with the same oncological results obtained with open surgery while today it is considered the gold standard of treatment only for small gastric GIST. Controversy surrounds the maximum diameter of GIST for laparoscopic resection. We present our experience of 33 cases of GIST at Sant'Anna Hospital (Ferrara) in a period between 1999 and 2017 with a literature review.

Laparoscopic resection of gastrointestinal stromal tumors: Does laparoscopic surgery provide an adequate oncologic resection?

Gastrointestinal stromal tumors (GISTs) are rare tumors of the GI tract. Surgical resection remains the mainstay of non-metastatic disease. However, the ability to provide an adequate oncologic resection using laparoscopic surgery is still an area of debate. This is a thorough review of the current literature, looking particularly at the use of laparoscopic surgery for larger GISTs and the long-term oncologic outcomes compared to the results of open surgery. Laparoscopic resections provide an adequate oncologic result for GISTs of all sizes, including those greater than 5 cm in size.

Gastrointestinal stromal tumors: surgical treatment and targeted therapy

To improve surgical and complex treatment of patients with gastrointestinal stromal tumors (GIST). Our analysis included 97 GIST patients who were at Petrovsky Russian Research Center of Surgery and Moscow City Oncological Hospital #62 from January 2006 to September 2016. Advisability of surgery for GIST patients was confirmed. We have assessed surgical outcomes, defined the indications for adjuvant targeted therapy depending on GIST prognostic risk and additional factors for unfavorable course of disease. It was concluded that surgical treatment is preferred for patients with resectable GISTs. Adjuvant therapy is indicated in patients with high risk of progression if mutations indicating tumor sensitivity to the drugs are revealed. Adjuvant targeted therapy is not indicated in patients with low and very low risk of progression.

Prognostic Value of Her2/neu Expression in Gastrointestinal Stromal Tumors: Immunohistochemical Study.

Background:Gastrointestinal stromal tumor (GIST) is a relatively rare type of neoplasms. In Egypt, it represents 2.5% of gastrointestinal tumors and 0.3% of all malignancies. Most of the GISTs develop in the stomach.Aim:To reveal the significance of Her2/neu immunohistochemical expression in GIST and its correlation with other histopathologic parameters and tumor relapse after regular follow-up.Patients and methods:This study is a retrospective and prospective cohort. It included 32 patients with GISTs, who were resectable with no distant metastasis. Immunohistochemical staining by Her2/neu was performed after complete surgical resection of the tumors with preservation of the pseudocapsule.Results:In total, 53.1% of cases were men and 46.9% women. Tumors were classified into low-risk (25%), intermediate-risk (21.9%), and high-risk groups (53.1%). Her2/neu expression was negative in 56.3% of GISTs and positive in 43.7%. Its expression was significantly correlated with risk grade (P = .04), tumor size (P = .001), mitotic count (P = .00), and increased risk of relapse (P = .00). Furthermore, tumor relapse was significantly correlated with the tumor mitotic counts (P = .00). Using kappa agreement test, it showed that 4 mitotic counts/50 high-power fields (HPF) was the cutoff value with which the tumor might be associated more with relapse, with 83% sensitivity, 70% specificity, and P value of .003.Conclusions:Her2/neu might be used as an independent prognostic marker for tumor recurrence after complete resection of GIST, and the cutoff value of mitotic count that might predict tumor relapse is 4/50 HPF. However, more clinical studies with greater number of cases with fluorescent in situ hybridization integration are recommended.

Imatinib mesylate-induced kidney injury in the treatment of a gastrointestinal stromal tumor

Gastrointestinal stromal tumors (GISTs) are a rare type of neoplasm arising within the gastrointestinal tract. Current treatment guidelines employ target-based therapy and adjuvant treatment with imatinib mesylate. We report a case of imatinib-induced renal injury in a 48-year-old male undergoing adjuvant chemotherapy after surgical resection of a rectal GIST. Upon initiation of imatinib therapy, the patient’s serum creatinine steadily rose and met criteria for kidney injury after twenty months of therapy. Drug discontinuation led to a normalization of renal function, but upon reinitiating therapy the serum creatinine sharply increased again. The patient’s recurrent acute renal injury led to indefinite drug discontinuation. Imatinib toxicities have been well studied; however, there are no reports to date noting its renal effects in the GIST patient population. This case report highlights imatinib as therapy for GISTs, describes an event of imatinib-induced renal injury, and reviews current treatment modalities.

Comparison of Different Risk Classification Systems in 558 Patients with Gastrointestinal Stromal Tumors after R0-Resection

Background: Due to adjuvant treatment concepts for patients with R0-resected gastrointestinal stromal tumors (GIST), a reproducible and reliable risk classification system proved of utmost importance for optimal treatment of patients and prediction of prognosis. The aim of this study was to reevaluate the impact of five widely-applied and well-established GIST risk classification systems (i.e., scores by Fletcher, Miettinen, Huang, Joensuu, and TNM classification) on a series of 558 GIST patients with long-term follow-up after R0 resection.Methods: Tumor size, mitotic count and site were used in variable combination to predict high- and low risk patients by the use of the five risk classification models. For survival analyses disease-specific survival, disease-free survival and overall-survival were investigated. Patients with initial metastatic disease or incompletely resectable tumors were excluded.Results: All GIST classification models distinguished well between patients with high-risk and low-risk tumors and none of the five risk systems was superior to predict patient outcome. The models showed significant heterogeneity. There was no significant difference between the different risk-groups regarding overall-survival. Subdivision of GIST patients with very low- and low-risk appeared to be negligible.Conclusions: Currently applied GIST risk classification systems are comparable to predict high- or low-risk patients with initial non-metastatic and completely resected GIST. However, the heterogeneity of the high-risk group and the absence of differences in overall survival indicate the need for more precise tumor- and patient-related criteria for better stratification of GIST and identification of patients who would benefit best from adjuvant tyrosine kinase inhibitor therapy.

Treatment and prognosis of 108 patients with high-risk gastrointestinal stromal tumor

To investigate the treatment methods and prognostic factors of high-risk gastrointestinal stromal tumor (GIST). Clinicopathological date and follow-up data of 108 patients with high-risk GIST from January 2002 to February 2016 treated at our department were retrospectively reviewed. The patients were divided into two groups according to whether they received adjuvant therapy after surgery. A group of patients received imatinib adjuvant therapy(adjuvant therapy group, 69 cases). Another group of patients were not treated with imatinib until they were found to have disease progression(follow-up observation group, 39 cases). The survival rate and recurrence rate were compared between two groups, and the risk factors of prognosis were analyzed by Cox regression model. All the cases were followed up with a median time of 48 months(1 to 161 months). Recurrence and / or metastasis occurred in 57(52.8%) patients during follow-up. The postoperative recurrence and / or metastasis rate was 34.8%(24/69) and 84.6%(33/39) respectively in the adjuvant therapy group and the follow-up observation group, the difference was statistically significant(P=0.000). Twenty-eight(25.9%) patients died. The 1-, 3-, 5-, 10-year survival rates of the 108 patients undergoing follow-up were estimated to be 99.8%, 87.7%, 76.0% and 42.7% respectively. The 5-year survival rates were 79.3% and 72.3% in the adjuvant therapy group and the follow-up observation group, the difference was not statistically significant (P=0.648). Univariate analysis showed that mitotic count, radical degree and tumor rupture were predictive factors of survival after resection of primary high-risk GIST (all P<0.05). Multivariate analysis using Cox regression model revealed that the mitotic count (P=0.013, RR=2.400, 95%CI:1.206 to 4.779) and radical degree(P=0.003, RR=3.968, 95%CI:1.609 to 9.784) were independent prognostic factors. Comprehensive treatment of radical surgery combined with targeted therapy and close followed up can lead to better long-term survival of high-risk patients with GIST.

Endoscopic Submucosal Dissection vs. Surgical Resection of Gastrointestinal Stromal Tumors in North America

Introduction: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. The primary method of resecting these neoplasms is via laparoscopic or open surgery. Surgical procedures are associated with high cost, morbidity and mortality. In recent years, less invasive procedures such as endoscopic submucosal dissection (ESD) have been used to resect GISTs. The aim of this retrospective study is to investigate the clinical efficacy, safety, and feasibility of endoscopic vs surgical interventions in resection of GISTs. Methods: This was a single center retrospective study in which we compared the data of patients with GISTs who had undergone endoscopic (endoscopic group) versus surgical (control group) resection from 2014 to 2016. Only gastric tumors up to 5 cm in size were included in the study. Surveillance was performed with CT abdomen, EGD or close oncology follow-up at 3-12 month intervals. Main outcome measures were recurrence rate, operative time, postoperative complications, hospital stays, and analgesic requirement. Results: Out of 14 patients in the endoscopic group, 12 met our criteria. Endoscopic enucleation was performed for endophytic lesions and endoscopic full thickness resection (EFTR) performed for exophytic lesions. Out of 21 patients in the control group, 6 met criteria. Three patients had open wedge resection and three had laparoscopic resection. There was one moderate grade GIST in the endoscopic group but all others in both groups were low grade. The mean endoscopic removal time was 79.7 minutes. There were no significant complications in either group. However, surgical patients required analgesics including opioids, acetaminophen, throughout the whole hospitalization with greater frequency and duration. 9 out of 12 patients treated endoscopically required hospital admission while all six surgical patients were admitted. Endoscopic patients had shorter post-operative lengths of stay compared to surgery patients (2.08 vs 8.33 days). No recurrence was noted in either group. Conclusion: Endoscopic removal of gastric GISTs up to 5 cm in size is a safe and effective alternative to surgical resection with additional benefits of shorter length of hospital stay, decreased opioid use, and lower costs. It may be considered as an alternative method of GIST resection in centers with trained endoscopists.

A Young Man with an Abnormal Chest X-ray

Gastrointestinal stromal tumors(GIST) are an uncommon neoplasms of the GI tract. We present a rare case of esophageal GIST in a previously healthy young male. A 30 year old male presented to the ED after waking up ith cough, eigastric pain, nausea and vomiting. A chest x- ray showed upper mediastinal widening. Contrast enhanced CT scan incshowed a posterior mediastinal mass. Transbronchial needle aspiration and biopsy of a subcarinal mass was performed which revealed necrotic tissuecand was not diagnostic. Repeat biopsy with right video assisted thoracic surgery was performed. Immunohistochemistry was positive for CD117. A repeat chest x-ray 3 months later revealed resolution of previously described mass. He remained well until 10 months after initial presentation when he presented with chest pain, back pain and dry cough. A chest CT revealed a recurrent 5 cm subcarinal density. Right thoracotomy and resection of the mass was performed. Pathology results showed GIST with high mitotic rate. Patient was started on Imatinib. Endoscopic ultrasound two months later showed a residual mass. Fine needle aspiration and biopsy was positive for GIST. He underwent esophagectomy. Histologic evaluation revealed high grade epithelioid GIST. Patient has been asymptomatic without recurrence since.Figure 1Figure 2Figure 3GISTs affect mainly older individuals. It occurs mainly in stomach and express KIT or cell surface marker cd117 in 85-90% of cases, which is a tyrosine kinase receptor. Initial patient evaluation is usually with CT scan. Radical surgery is the treatment of choice in primary resectable GISTs. Almost all are associated with a risk of recurrence with rate of 40-50%. Imatinib Mesylate, inhibitor of KIT Tyrosine Kinase is used as an adjuvant therapy to decrease the risk of post operative recurrence. High risk tumors have a risk of 66% recurrence, making it obvious that surgery alone is not sufficient to provide long term survival. It is also used as neoadjuvant in cases that complete surgical resection is impossible and also for reducing tumor size. Since patients with high risk GIST relapse within 2 years, the follow up should be adopted to tumor criteria. CTS in the technique of choice for follow up. Our patient is particularly unique because of the age of presentation and location of tumor. Immunohistochemistry for CD117 has a high value of specificity for GIST. Treatment is complete resection. Recurrence is mainly dependent on mitotic activity. Imatinib is a useful adjuvant.

SMALL BOWEL VERSUS GASTRIC SURGERY FOR GASTROINTESTINAL STROMAL TUMORS

Objectives. The aim of the study was to compare the postoperative and oncologic outcomes of small bowel versus gastric surgery for gastrointestinal stromal tumors (GISTs). Background. The feasibility of the small bowel resection for GIST has been demonstrated; however, its impact on outcomes, particularly its oncologic safety for tumors greater than 5 cm, remains unknown. Methods. Among 93 patients treated for a stromal tumor in SUUB between 2001 and 2015, patients who underwent primary resection for a gGIST smaller than 20 cm (N = 66), by either small bowel (group S, n = 28) or gastric surgery (group G, n = 38), were compared. Multivariable analyses and propensity score matching were used to compensate for differences in baseline characteristics. Results. In hospital mortality and morbidity rates in groups S and G were 0.0% versus 2.6% (P = 0.086) and 10.7% vs 18.4% (P = 0.004), respectively. Small bowel resection was independently protective against in hospital morbidity (odds ratio 0.54, P = 0.014). The rate of R0 resection was 96.4% in group S and 92.1% in group G (P = 0.103). After 1:1 propensity score matching (n= 22), the groups were comparable according to age, sex, tumor location and size, mitotic index, American Society of Anaesthesiology score, and the extent of surgical resection. After adjustment for BMI, overall morbidity (9.1% vs 19.6%; P = 0.005), surgical morbidity (4.5% vs 9.1%; P = 0.048), and medical morbidity (4.5% vs 13.6%; P = 0.01) were significantly lower in group S. Five year recurrence- free survival was significantly better in group S (89.3% vs 82.6%; P = 0.011). In tumors greater than 5 cm, in hospital morbidity and 5 year recurrence- free survival were similar between the groups (P = 0.255 and P = 0.423, respectively). Conclusions. Small bowel resection for GISTs is associated with favourable short term outcomes without compromising oncologic results.

Promoter methylation of PCDH10 by HOTAIR regulates the progression of gastrointestinal stromal tumors

HOTAIR, a long non-coding RNA (lncRNA), plays a crucial role in tumor initiation and metastasis by interacting with the PRC2 complex and the modulation of its target genes. The role of HOTAIR in gastrointestinal stromal tumors (GISTs) is remains unclear. Herein we investigate the mechanism of HOTAIR in the genesis and promotion of GISTs. The expression of HOTAIR was found to be higher in surgically resected high-risk GISTs than that in low- and intermediate-risk GISTs. Using GIST-T1 and GIST882 cells, we demonstrated that HOTAIR repressed apoptosis, was associated with cell cycle progression, and controlled the invasion and migration of GIST cells. Using a gene expression microarray and lists of HOTAIR-associated candidate genes, we suggested that protocadherin 10 (PCDH10) is a key molecule. PCDH10 expression was significantly decreased in GIST-T1 and GIST882 cells, possibly as a consequence of hypermethylation. We observed that HOTAIR induced PCDH10 methylation in a SUZ12-dependent manner. In this study, we found that the malignant character of GISTs was initiated and amplified by PCDH10 in a process regulated by HOTAIR. In summary, our findings imply that PCDH10 and HOTAIR may be useful markers of disease progression and therapeutic targets.

Efficacy of laparoscopic or open surgery for gastrointestinal stromal tumors and effects of different risk level on prognosis

Objective To compare the efficacy of laparoscopic or open surgery for gastrointestinal stromal tumors (GISTs) and investigate effects of different risk level on prognosis. Methods The retrospective cohort study was adopted. The clinical data of 192 patients with GISTs who were admitted to Zhongshan Hospital of Fudan University from January 2008 to December 2013 were collected. Among the 192 patients, 88 undergoing laparoscopic surgeries were allocated into the laparoscopic surgery group, 104 patients undergoing open surgeries were allocated into the open surgery group. The following indicators were observed: (1) operative status: surgical procedure, operation time, volume of intraoperative blood loss. (2) Status of postoperative recovery: time of gastrointestinal function recovery, time of drainage tube removal, complications and duration of hospital stay. (3) Follow-up status. (4) Prognosis of patients in different risk level. The follow-up using outpatient examination and telephone interview was performed to assess patients′ survival, tumor recurrence and metastasis until June 2015. Measurement data with normal distribution were presented as ±s and comparison between groups was evaluated by the t test. Comparison of count data was analyzed by the chi-square test. The Kaplan-Meier method was used to draw survival curve and calculate the overall survival rate and relapse-free survival rate. Results (1) Operative status: of the 88 patients in the laparoscopic surgery group, 1 underwent laparoscopic wedge gastrectomy+ cholecystectomy+ appendectomy, 6 underwent laparoscopic wedge gastrectomy+ cholecystectomy, 14 underwent laparoscopic assisted partial gastrectomy, 67 underwent laparoscopic wedge gastrectomy. Of the 104 patients in the open surgery group, 1 underwent partial gastrectomy+ splenectomy, 2 underwent partial gastrectomy combined with distal pancreatectomy+ splenectomy, 2 underwent total gastrectomy, 7 underwent distal subtotal gastrectomy, 7 underwent wedge gastrectomy+ partial or total adjacent organ resection, 8 underwent proximal subtotal gastrectomy, 8 underwent wedge gastrectomy+ cholecystectomy, 69 underwent wedge gastrectomy. The operation time and volume of intraoperative blood loss were (105±33)minutes and (43±16)mL in the laparoscopic surgery group, (121±52)minutes and (199±81) mL in the open group, respectively, with statistically significant differences between the 2 groups (t=-2.104, 2.632, P 0.05). (3) Follow-up status: Of the 192 patients, 149 received follow-ups. Of 88 patients in the laparoscopic surgery group, 68 were followed up for an average time of 39 months. Of 104 patients in the open surgery group, 81 were followed up for an average time of 51 months. During the follow-up, tumor recurrence rate in the laparoscopic surgery group and open surgery group was respectively 8.8%(6/68) and 21.0%(17/81), with no statistically significant difference between the 2 groups (χ2=1.888, P>0.05 ). Postoperative 1-, 3-, 5 year survival rates were 98.5%, 92.9%, 87.4% and 91.7%, 85.2%, 76.9% in the laparoscopic surgery group and open surgery group, respectively, with no statistically significant difference between the 2 groups (χ2=1.967, P>0.05). (4) Prognosis of patients in different risk level: of the 149 who received the follow-up, the tumor recurrence rate of patients in low, intermediate and high recurrence risk was 7.0%(5/71), 13.6%(6/44) and 35.3%(12/34), respectively, with a statistically significant difference among the above indexes (χ2=14.637, P 0.05). Five-year relapse-free survival rate of low, intermediate and high risk patients was 94.2%, 80.0% and 61.8% respectively, with a statistically significant difference (χ2=13.547, P 0.05). Conclusions Compared to open resection, laparoscopic GISTs resection offers better short-term outcomes, however, the two surgical techniques offer equal long-term outcomes. Patients of high risk have poor prognosis. Key words: Gastrointestinal stromal tumors; Gastrectomy; Open surgery; Laparoscopy; Prognosis