Gastrointestinal stromal tumors, intramural leiomyomas, and leiomyosarcomas in the duodenum: a clinicopathologic, immunohistochemical, and molecular genetic study of 167 cases

Pancreaticoduodenectomy versus local resection in the treatment of gastrointestinal stromal tumors of the duodenum

Background

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms. However, duodenal GISTs compromise a small and rare subset and few studies have focused on them. We evaluated the surgical management of patients with duodenal GISTs treated by pancreaticoduodenectomy (PD) versus local resection (LR) in our institution and analyzed the postoperative outcomes.

Methods

This was a retrospective review of patients with duodenal GISTs managed in our institution from January 2006 to January 2012. Clinicopathologic findings and disease-free survival (DFS) of duodenal GIST patients were analyzed.

Results

A total of 48 patients were selected. The most common presentation was bleeding (60.4%), and the second portion of the duodenum (35.4%) was the most common dominant site. Of the patients, 34 (70.8%) underwent LR while 14 (29.2%) underwent PD. The surgical margins for all studied patients were free. Patients who ultimately underwent PD were more likely to present with a larger tumor (median size: PD, 6.3 cm vs LR, 4.0 cm; P = 0.02) and more commonly presented with a tumor in the second portion of the duodenum (second portion: PD, 64.3% vs LR, 23.5%; P = 0.007). The tumors treated by PD had a higher grade of risk compared with LR as defined by National Institutes of Health (NIH) criteria (P = 0.019). PD was significantly associated with a longer operation time and a longer hospital stay compared to LR (P < 0.001 and P = 0.001, respectively). In our study, the median follow-up period was 36 months (range: 0 to 81 months). The 1- and 3-year DFS was 100% and 88%, respectively. From multivariable analysis, the only significant factor associated with a worse DFS was an NIH high risk classification (hazard ratio = 4.24).

Conclusions

The recurrence of duodenal GIST was correlated to tumor biology rather than type of operation. PD was associated with a longer hospital stay and longer operation time. Therefore, LR with clear surgical margins should be considered a reliable and curative option for duodenal GIST and PD should be reserved for lesions not amenable to LR.

Extended adjuvant therapy with imatinib in patients with gastrointestinal stromal tumors : recommendations for patient selection, risk assessment, and molecular response monitoring

On the basis of the recently published results of a clinical trial comparing 12 and 36 months of imatinib in adjuvant therapy for gastrointestinal stromal tumors (GISTs), which demonstrated clinical benefit of longer imatinib treatment in terms of delaying recurrences and improving overall survival, both the US Food and Drug Administration and the European Medicines Agency have updated their recommendations and approved 36 months of imatinib treatment in patients with v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT)-positive GISTs (also known as CD117-positive GISTs) at high risk of recurrence after surgical resection of a primary tumor. This article discusses patient selection criteria for extended adjuvant therapy with imatinib, different classifications of risk of recurrence, and assessment of the response to therapy.

Gastrointestinal stromal tumors: risk assessment and adjuvant therapy

Adjuvant imatinib prolongs recurrence-free survival and probably overall survival of patients who have undergone surgery for gastrointestinal stromal tumor (GIST). Estimation of the risk of recurrence with a prognostication tool and tumor mutation analysis is essential before imatinib initiation, because approximately 60% of patients with GIST with operable tumor are cured by surgery alone and some mutated tyrosine kinases are insensitive to imatinib. Adjuvant imatinib is usually administered for 3 years at the dose of 400 mg once daily. Early detection of tumors that recur despite adjuvant therapy with longitudinal imaging of the abdomen is likely beneficial.

A large gastrointestinal stromal tumor of the duodenum treated by partial duodenectomy with Roux-en-Y duodenojejunostomy: a case report

Introduction

Duodenal gastrointestinal stromal tumors are uncommon and a relatively small subset of gastrointestinal stromal tumors whose optimal surgical procedure has not been well defined. Because submucosal spread and local lymph node involvement are infrequent in gastrointestinal stromal tumors, wide margins with routine lymph node dissection may not be required. Various surgical procedures for duodenal gastrointestinal stromal tumor, pancreatoduodenectomy, pancreas-sparing duodenectomy, segmental duodenectomy, or local resection, have been described depending on the size and exact site of the lesion.

Case presentation

We present the case of a 65-year-old African woman with a giant gastrointestinal stromal tumor involving the second and third portion of the duodenum successfully treated by partial duodenectomy with duodenojejunostomy. This surgical technique is ideal when a gastrointestinal stromal tumor does not involve the ampulla because it avoids a pancreatoduodenectomy, and has not been previously described for the management of this malignancy. Duodenal gastrointestinal stromal tumor should be suspected in any patient with a duodenal wall mass.

Conclusions

Gastrointestinal stromal tumors of the duodenum should be suspected in any patient with a duodenal wall mass. Extramural growth and central ulceration with or without bleeding should alert the endoscopist to the possibility of a duodenal gastrointestinal stromal tumor diagnosis.

Clinicopathological features of primary leiomyosarcoma of the gastrointestinal tract following recognition of gastrointestinal stromal tumours

AIMS

We aimed to elucidate the clinicopathological and immunohistochemical features of leiomyosarcoma (LMS) of the gastrointestinal (GI) tract.

METHODS AND RESULTS

We encountered seven cases of GI-LMS in the colon (n = 4), rectum (n = 1), jejunum (n = 1) and stomach (n = 1). They ranged from 1 to 25 cm (median, 8.5 cm) in size and had high mitotic counts (median 38 per 50 high-power fields). Morphologically, the tumours were composed mainly of spindle cells with eosinophilic cytoplasm and various degrees of nuclear atypia and pleomorphism. Immunohistochemically, the tumours were positive for α-smooth muscle actin (86%), muscle-specific actin (71%), desmin (86%), calponin (71%), h-caldesmon (57%) and smoothelin (71%). All were negative for KIT, CD34, protein kinase C theta and DOG1. Local recurrence and distant metastasis occurred in one and three patients, respectively. We then reviewed 55 cases of GI-LMS from the era following the recognition of gastrointestinal stromal tumours. Among 29 of 55 cases for whom follow-up information was available, the estimated 5-year overall survival rate was 51.6%; tumour size ≥5 cm was correlated significantly with shorter overall survival time (P = 0.0016), while mitotic count (≥50 or ≥100 per 50 high-power fields) proved to be no prognostic factor.

CONCLUSIONS

GI-LMSs have distinctive clinicopathological and immunohistochemical features and exhibit aggressive biological behaviour.

Duodenal gastrointestinal stromal tumor: clinicopathological characteristics, surgical outcomes, long term survival and predictors for adverse outcomes

BACKGROUND

Gastrointestinal stromal tumors (GISTs) occur rarely in the duodenum. Because of their low incidence, data on long-term survival and prognostic factors are limited. The aims of this study were to present the authors' experiences in the diagnosis and treatment of this disease and to evaluate long-term surgical outcomes.

METHODS

Clinical data from 22 consecutive patients with duodenal GISTs surgically managed from May 1999 to August 2011 were retrospectively studied. A pooled analysis was done by systematically reviewing other case series reported in the English literature. Recurrence-free survival and independent predictors of adverse outcomes were analyzed using the Kaplan-Meier method and multivariate Cox regression.

RESULTS

Duodenal GISTs had a mild male predominance (68.2%), occurring primarily in older adults (median age, 58 years), with a frequency of 7.49% among all GISTs. Clinical presentations were nonspecific, with gastrointestinal bleeding and abdominal pain or discomfort being the most common symptoms. The tumors were located mainly in the second portion of the duodenum, in 14 patients (63.6%), with a median size of 3.75 cm (range, 1.4 to 14). All patients underwent curative surgical resection, including 9 pancreaticoduodenectomy, 3 segmental duodenectomy, and 10 local resection. Eighteen patients were alive without evidence of recurrence after a median follow-up period of 67.5 months (range, 3 to 118). The 1-year, 2-year, and 3-year rates of recurrence-free survival were 95%, 89.5%, and 86.7%, respectively. Kaplan-Meier analysis and log-rank tests showed that surgical pattern, mitosis, and risk grade were significantly associated with recurrence-free survival (P < .05 for all). However, only high mitosis was a significant predictive factor for adverse outcomes on multivariate analysis (hazard ratio, 16.414; 95% confidence interval, 1.914 to 140.756; P = .011).

CONCLUSIONS

Duodenal GIST is an unusual neoplasm with favorable survival after curative resection. Mitotic activity was more influential than tumor size and risk grade in predicting adverse outcomes. All patients with duodenal GISTs require long-term follow-up, because late relapse can occur even if the tumor has low malignant potential.

Duodenal wedge resection for large gastrointestinal stromal tumour presenting with life-threatening haemorrhage

Background. Duodenal gastrointestinal stromal tumours (GISTs) are an uncommon malignancy of the gastrointestinal (GI) tract. We present a case of life-threatening haemorrhage caused by a large ulcerating duodenal GIST arising from the third part of the duodenum managed by a limited duodenal wedge resection. Case Presentation. A 61-year-old patient presented with acute life-threatening gastrointestinal bleeding. After oesophagogastroduodenoscopy failed to demonstrate the source of bleeding, a 5 cm ulcerating exophytic mass originating from the third part of the duodenum was identified at laparotomy. A successful limited wedge resection of the tumour mass was performed. Histopathology subsequently confirmed a duodenal GIST. The patient remained well at 12-month followup with no evidence of local recurrence or metastatic spread. Conclusion. Duodenal GISTs can present with life-threatening upper GI haemorrhage. In the context of acute haemorrhage, even relatively large duodenal GISTs can be treated by limited wedge resection. This is a preferable alternative to duodenopancreatectomy with lower morbidity and mortality but comparable oncological outcome.

Duodenal gastrointestinal stromal tumors (GISTs): arguments for conservative surgery

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) of the duodenum are rare. We sought to evaluate the postoperative courses and long-term outcomes of conservative surgery (CS) versus pancreaticoduodenectomy (PD) for patients with non-metastatic duodenal GISTs.

METHODS

Seventeen patients underwent surgery for duodenal GISTs between January 2000 and January 2012; 11 patients underwent CS (CS group), and six patients underwent a PD (PD group).

RESULTS

Mortality was similar between the two groups. Patients in the PD group had longer operative times, more tumors located on the pancreatic side of the duodenum, higher rates of post-operative complications including postoperative pancreatic fistulas, and a longer hospital stay, when compared with patients of CS group. All tumors were resected with clear surgical margins (R0 resection). The median disease-free survival times were not different.

CONCLUSION

CS was safe and provided similar oncologic outcomes as PD. CS should be the procedure of choice in patients with GIST that does not involve the pancreatic side of the duodenum.

Limited resection for duodenal gastrointestinal stromal tumors: Surgical management and clinical outcome

AIM: To analyze our experience in patients with duodenal gastrointestinal stromal tumors (GIST) and review the appropriate surgical approach.

METHODS: We retrospectively reviewed the medical records of all patients with duodenal GIST surgically treated at our medical institution between 2002 and 2011. Patient files, operative reports, radiological charts and pathology were analyzed. For surgical therapy open and laparoscopic wedge resections and segmental resections were performed for limited resection (LR). For extended resection pancreatoduodenectomy was performed. Age, gender, clinical symptoms of the tumor, anatomical localization, tumor size, mitotic count, type of resection resectional status, neoadjuvant therapy, adjuvant therapy, risk classification and follow-up details were investigated in this retrospective study.

RESULTS: Nine patients (5 males/4 females) with a median age of 58 years were surgically treated. The median follow-up period was 45 mo (range 6-111 mo). The initial symptom in 6 of 9 patients was gastrointestinal bleeding (67%). Tumors were found in all four parts of the duodenum, but were predominantly located in the first and second part of the duodenum with each 3 of 9 patients (33%). Two patients received neoadjuvant medical treatment with 400 mg imatinib per day for 12 wk before resection. In one patient, the GIST resection was done by pancreatoduodenectomy. The 8 LRs included a segmental resection of pars 4 of the duodenum, 5 wedge resections with primary closure and a wedge resection with luminal closure by Roux-Y duodeno-jejunostomy. One of these LRs was done minimally invasive; seven were done in open fashion. The median diameter of the tumors was 54 mm (14-110 mm). Using the Fletcher classification scheme, 3/9 (33%) tumors had high risk, 1/9 (11%) had intermediate risk, 4/9 (44%) had low risk, and 1/9 (11%) had very low risk for aggressive behaviour. Seven resections showed microscopically negative transsection margins (R0), two showed positive margins (R1). No patient developed local recurrence during follow-up. The one patient who underwent pancreatoduodenectomy died due to progressive disease with hepatic metastasis but without evidence of local recurrence. Another patient died in complete remission due to cardiac disease. Seven of the nine patients are alive disease-free.

CONCLUSION: In patients with duodenal GIST, limited surgical resection with microscopically negative margins, but also with microscopically positive margins, lead to very good local and systemic disease-free survival.

Predictors of survival and recurrence in primary leiomyosarcoma

BACKGROUND

Leiomyosarcoma is a soft tissue sarcoma whose outcome has historically been confounded by the inclusion of gastrointestinal stromal tumors. Thus, we sought to determine the factors that predict survival and recurrence in patients with primary leiomyosarcoma alone.

METHODS

During 1982-2006, a total of 353 patients with primary resectable leiomyosarcoma were identified from a prospective database. Multivariate analysis was used to assess clinicopathologic factors for association with disease-specific survival (DSS). Competing risk survival analysis was used to determine factors predictive for local and distant recurrence.

RESULTS

Of 353 patients, 170 (48 %) presented with extremity, 144 (41 %) with abdominal/retroperitoneal, and 39 (11 %) with truncal tumors. Median age was 57 (range, 18-88) years, and median follow-up was 50 (range, 1-270) months. Most tumors were high grade (75 %), deep (73 %), and completely resected (97 %); median size was 6.0 (range, 0.3-45) cm. Abdominal/retroperitoneal location was associated with worse long-term DSS compared to extremity or trunk (P = 0.005). However, by multivariate analysis, only high grade and size were significant independent predictors of DSS. Overall, 139 patients (39 %) had recurrence: 51 % of those with abdominal/retroperitoneal, 33 % of extremity, and 26 % of truncal disease. Significant independent predictors for local recurrence were size and margin, whereas predictors for distant recurrence were size and grade. Site was not an independent predictor of recurrence; however, late recurrence (>5 years) occurred in 9 % of abdominal/retroperitoneal and 4 % of extremity lesions.

CONCLUSIONS

Grade and size are significant independent predictors of DSS and distant recurrence. Long-term follow-up in leiomyosarcoma is important, as late recurrence continues in 6-9 % patients.

Neurofibromatosis type 1, gastrointestinal stromal tumor, leiomyosarcoma and osteosarcoma: four cases of rare tumors and a review of the literature

BACKGROUND

Neurofibromatosis type 1 (NF1) is a genetic syndrome that predisposes patients to benign and malignant tumor development. Patients with NF1 develop multiple neurofibromas that can transform into aggressive sarcomas known as malignant peripheral nerve sheath tumors. In contrast, malignant tumors unrelated to the nervous system rarely coexist with neurofibromatosis. The aim of this article was to present four cases of adult NF1 patients with malignant tumors unrelated to the nervous system as well as a bibliographic search for papers describing these tumors in NF1, focusing on osteosarcomas, gastrointestinal stromal tumors (GISTs), leiomyosarcomas and somatostatinomas and their genetic alterations in NF1.

METHODS

Search engines such as PubMed and MEDLINE were browsed for English-language articles since 1989 using a list of keywords, as well as references from review articles. Search terms were NF1, osteosarcoma, leiomyosarcoma, somatostatinoma and GIST. Data were summarized in a table at the end of the Results section.

RESULTS

In our four NF1 cases, there were one osteosarcoma, one leiomyosarcoma, one somatostatinoma and GIST and one GIST. NF1 was diagnosed at an adult age when these patients were admitted to our oncology department. The results generated by the literature search yielded 75 articles about NF and GIST. We summarized the clinical characteristics of 43 patients with NF1 and somatostatinoma. Forty-five articles involving NF and osteosarcoma were found, and of these, 26 involved NF1; from these articles, we identified the clinical features of 8 patients. Twenty-five articles were found concerning NF1 and leiomyosarcoma, and of those, we summarized the clinical features of 15 patients.

CONCLUSIONS

Here we reviewed somatostatinomas, GISTs, osteosarcomas and leiomyosarcomas occurring in NF1 patients. Patients with NF1 who present with gastrointestinal symptoms, should be carefully evaluated carefully with a high index of suspicion of potential GISTs, periampullary and duodenal tumors. Patients with pathological fractures or bone pain along with NF1 should be carefully screened for malignant bone tumors. Patients with NF1 can develop leiomyosarcoma less frequently than other malignancies, but the association of uterine leiomyoma and NF1 may not be fortuitous. Somatic mutations were defined for frequent tumors, including neurogenic tumors and GISTs but not for sarcomas due to the complexity of underlying mechanisms of the disease and tumorigenesis. Based on the findings; all NF patients can develop malignant tumors, including the less frequently observed ones. Therefore, we recommend that new genetic studies should be performed for rare malignancies in cases of NF1.

Feasibility and oncological outcomes of limited duodenal resection in patients with primary nonmetastatic duodenal GIST

INTRODUCTION

Duodenal gastrointestinal stromal tumors (GISTs) are rare but still represent approximately 30 % of primary duodenal tumors. This study aimed to audit the feasibility and oncological outcomes of limited duodenal resection in patients with primary nonmetastatic duodenal GIST.

METHODS

Twelve patients who underwent surgery at our institution since 2002 were prospectively followed up. The duodenal GISTs were located in the first (n = 3), second (n = 1), third (n = 3), and fourth of duodenum (n = 1). Involving both D1/D2 (n = 2), D2/D3 (n = 1), and D3/D4 (n = 1). The primary endpoint for this analysis was disease-free survival.

RESULTS

The commonest presentation was melena and anemia (83 %). All the patients underwent limited resection; six wedge resections with primary closures and six segmental resections with end-to-end anastomosis. The median tumor size was 8 cm (range, 5-16 cm). According to Fletcher scale, two GISTs were low risk, while 10 patients were intermediate and high risk. The latter received adjuvant therapy. All the patients had a complete resection with no postoperative mortality. One patient had three liver metastases 4 months after limited resection and had partial hepatectomy. After median follow-up of 45 (15-78) months, all patients are alive and disease free.

CONCLUSION(S)

When technically feasible, limited resection should be considered a reliable and curative option for duodenal GIST achieving satisfactory disease-free survival. The technical feasibility is guided by the tumor size, possible adjacent organ involvement, and its exact anatomical location.

Gastrointestinal stromal tumour of the duodenum: single institution experience

BACKGROUND

Primary gastrointestinal stromal tumours (GISTs) of the duodenum are rare. The aim of this study was to review the surgical management of GISTs in this anatomically complex region.

METHODS

Retrospective review from January 1999 to August 2011 of patients with primary GISTs of the duodenum.

RESULTS

Forty-one patients underwent resection of duodenal GISTs. All operations were performed with intent to cure with negative margins of resection. The most common location of origin was the second portion of the duodenum. Local excision (n= 19), segmental resection with primary anastomosis (n= 11) and a pancreatoduodenectomy (n= 11) were performed. Two patients underwent an ampullectomy with local excision. Peri-operative mortality and overall morbidity were 0 and 12, respectively. Patients with high-risk GISTs (P= 0.008) and those who underwent a pancreatoduodenectomy (P= 0.021) were at a greater risk for morbidity. The median follow-up was 18 months. Eight patients developed recurrence. High-risk GISTs and neoplasms with ulceration had the greatest risk for recurrence (P= 0.017, P= 0.029 respectively). The actuarial 3- and 5-year survivals were 85% and 74%, respectively.

CONCLUSION

The choice and type of resection depends on the proximity to the ampulla of Vater, involvement of adjacent organs and the ability to obtain negative margins. The morbidity depends on the type of procedure for GIST.

Duodenal gastrointestinal stromal tumors: review on clinical and surgical aspects

INTRODUCTION

Gastrointestinal stromal tumors (GISTs) arising in the duodenum represent a rare entity and can be very demanding to manage. The diagnosis can be difficult (as these tumors can be misdiagnosed as pancreatic head tumors), and to treat owing to the complex anatomy of the duodenum and of the pancreatic head. Complete resection may require extensive procedures such as pancreaticodudodenectomy.

METHODS AND RESULTS

An extensive literature review regarding clinico-pathological features, diagnostic investigations and surgical options in the management of duodenal GISTs has been performed.

CONCLUSIONS

Duodenal GISTs have uncertain malignant potential, and they may be asymptomatic, or present with abdominal pain or bleeding. A preoperative diagnosis can be difficult to obtain. Endoscopic ultrasound and fine needle aspiration cytology (FNAC) may be helpful. Surgical R0 resection remains the only curative approach. However, owing to the complex anatomy of the duodenum, limited resection is not always feasible. In these cases, extensive procedures such as pancreaticoduodenectomy or pancreas-preserving duodenectomy are the treatment of choice.

Primary leiomyosarcomas of the gastrointestinal tract in the post-gastrointestinal stromal tumor era

Most mesenchymal neoplasms of the gastrointestinal tract are currently classified as gastrointestinal stromal tumors (GIST). Gastrointestinal stromal tumors are diagnosed by immunopositivity for CD117, CD34, and DOG1.1, with or without molecular analyses. According to the World Health Organization classification, the diagnosis of primary leiomyosarcomas of the gastrointestinal tract is so rare that there are no significant data on demographic, clinical, or gross features of this tumor. A comprehensive literature search was performed to identify gastrointestinal leiomyosarcomas. Searches were limited to the past 12 years because definitive tools to differentiate leiomyosarcomas from GIST were introduced in the late 1990s. Cases were included only if convincing data were presented. Six cases of esophageal leiomyosarcoma and 5 cases of gastric leiomyosarcoma were confirmed. Furthermore, 26 cases of leiomyosarcoma of the small bowel, 11 cases of the colon, and 8 cases arising in the rectum were identified. Finally, 28 cases of infantile and adolescent leiomyosarcoma were reviewed. Although survival analysis is precluded by small case numbers and limited survival data availability, the trend identifies that increased size and mitotic activity portends to a worse prognosis in small bowel leiomyosarcomas. Colonic leiomyosarcomas appear to be aggressive tumors, regardless of tumor size and mitotic activity. Rectal leiomyosarcomas present as smaller tumors with favorable prognosis. Leiomyosarcomas in post-GIST era are rare tumors of the gastrointestinal tract with distinctive clinicopathologic characteristics. Owing to different treatment options, it is necessary to accurately differentiate these from GIST, using a combination of histologic appearance, presence of smooth muscle antigens, and absence of specific GIST immunomarkers.

Presentation and management of gastrointestinal stromal tumors of the duodenum: a multi-institutional analysis

BACKGROUND

Duodenal gastrointestinal stromal tumors (GISTs) are a small subset of GISTs, and their management is poorly defined. We evaluated surgical management and outcomes of patients with duodenal GISTs treated with pancreaticoduodenectomy (PD) versus local resection (LR) and defined factors associated with prognosis.

METHODS

Between January 1994 and January 2011, 96 patients with duodenal GISTs were identified from five major surgical centers. Perioperative and long-term outcomes were compared based on surgical approach (PD vs LR).

RESULTS

A total of 58 patients (60.4%) underwent LR, while 38 (39.6%) underwent PD. Patients presented with gross bleeding (n = 25; 26.0%), pain (n = 23; 24.0%), occult bleeding (n = 19; 19.8%), or obstruction (n = 3; 3.1%). GIST lesions were located in first (n = 8, 8.4%), second (n = 47; 49%), or third/fourth (n = 41; 42.7%) portion of duodenum. Most patients (n = 86; 89.6%) had negative surgical margins (R0) (PD, 92.1 vs LR, 87.9%) (P = 0.34). Median length of stay was longer for PD (11 days) versus LR (7 days) (P = 0.001). PD also had more complications (PD, 57.9 vs LR, 29.3%) (P = 0.005). The 1-, 2-, and 3-year actuarial recurrence-free survival was 94.2, 82.3, and 67.3%, respectively. Factors associated with a worse recurrence-free survival included tumor size [hazard ratio (HR) = 1.09], mitotic count >10 mitosis/50 HPF (HR = 6.89), AJCC stage III disease (HR = 4.85), and NIH high risk classification (HR = 4.31) (all P < 0.05). The 1-, 3-, and 5-year actuarial survival was 98.3, 87.4, and 82.0%, respectively. PD versus LR was not associated with overall survival.

CONCLUSIONS

Recurrence of duodenal GIST is dependent on tumor biology rather than surgical approach. PD was associated with longer hospital stays and higher risk of perioperative complications. When feasible, LR is appropriate for duodenal GIST and PD should be reserved for lesions not amenable to LR.

Leiomyosarcoma of the sigmoid colon with multiple liver metastases and gastric cancer: a case report

Background

Leiomyosarcoma (LMS) of the gastrointestinal tract is an extremely rare high-grade neoplasm with poor prognosis. For advanced LMS with distant metastasis, the decision as to the choice of the most appropriate therapeutic strategy, including chemotherapy and surgery, is difficult. Here, we present an unusual case of LMS of the sigmoid colon with liver metastases and gastric cancer. The survival of this patient was prolonged by a combined modality therapy involving chemotherapy and surgery.

Case presentation

A 66-year-old woman who had been diagnosed with advanced gastric cancer and multiple liver metastases was referred to our hospital. The initial treatment with docetaxel and S-1 considerably reduced both the gastric cancer and liver tumors; consequently we performed surgical resection. Pathological examination revealed that no viable tumor cells remained in the stomach and chemotherapy resulted in complete remission of the gastric cancer. The liver tumors were immunohistochemically diagnosed as LMS. A tumor of the sigmoid colon was subsequently discovered and the liver tumors were found to have recurred. The surgically resected sigmoid colon and liver tumors were all immunohistochemically diagnosed as LMS. These findings indicated that the multiple liver metastases arose from the LMS in the sigmoid colon, and that they were accompanied by advanced gastric cancer. We performed another surgical resection and administered chemotherapy to treat the recurring liver metastases. The patient survived for 4 years and 10 months after initial presentation at our hospital.

Conclusion

Colonic LMS is rare and its joint occurrence with gastric cancer is extremely unusual. Although LMS is a high-grade neoplasm, a multimodal therapeutic approach can increase patient survival time even when multiple liver metastases are present.

Pathology of gastrointestinal stromal tumors

Gastrointestinal stromal tumor (GIST) is a well recognized and relatively well understood soft tissue tumor. Early events in GIST development are activating mutations in KIT or PDGFRA, which occur in most GISTs and encode for mutated tyrosine receptor kinases that are therapeutic targets for tyrosine kinase inhibitors, including imatinib and sunitinib. A small minority of GISTs possessing neither KIT nor PDGFRA mutations may have germline mutations in SDH, suggesting a potential role of SDH in the pathogenesis. Immunohistochemical detection of KIT, and more recently DOG1, has proven to be reliable and useful in the diagnosis of GISTs. Because current and future therapies depend on pathologists, it is important that they recognize KIT-negative GISTs, GISTs in specific clinical contexts, GISTs with unusual morphology, and GISTs after treatment. This review focuses on recent developments in the understanding of the biology, immunohistochemical diagnosis, the role of molecular analysis, and risk assessment of GISTs.

Laparoscopic pancreas-preserving subtotal duodenectomy for gastrointestinal stromal tumor

Gastrointestinal stromal tumors (GISTs) of the duodenum are rare neoplasms. The optimal surgical procedure is debated and several options ranging from limited resections to pancreaticoduodenectomy have been reported. The laparoscopic approach has been validated for gastric GISTs, but it does not yet represent a standard technique for tumors of the duodenum. We report the case of a localized duodenal GIST that was successfully treated by totally laparoscopic pancreas-preserving subtotal duodenectomy. This procedure may represent a feasible and effective treatment option for localized GISTs of the duodenum. Large series with long-term follow-up are needed.

Pancreas-preserving segmental duodenectomy for gastrointestinal stromal tumor of the duodenum and splenectomy for splenic angiosarcoma

BACKGROUND

Gastrointestinal stromal tumors are the most common mesenchymal tumors of the gastrointestinal tract and occur rarely in the duodenum. Splenic angiosarcoma is an aggressive neoplasm with an extremely poor prognosis.

METHODS

We report a case of a 70-year-old man hospitalized for abdominal pain in the upper quadrants, dyspepsia and nausea, previously treated for Hodgkin lymphoma 30 years ago. Abdominal CT showed a solid nodular lesion in the third portion of the duodenum, the presence of retropancreatic, aortic and caval lymph nodes, and four nodular splenic masses. (111)In-octreotide scintigraphy revealed pathological tissue accumulation in the duodenal region, and in the retropancreatic, retroduodenal, aortic and caval lymph nodes, suggesting a nonfunctioning neuroendocrine peripancreatic tumor.

RESULTS

At exploratory laparotomy, an exophytic soft tumor was found originating from the third portion of the duodenum. Pancreas-preserving duodenectomy with duodenojejunostomy, splenectomy and lymphnodectomy of retropancreatic aortic and caval lymph nodes were performed. Pathological evaluation and immunohistochemical studies showed the presence of a duodenal gastrointestinal stromal tumor with low mitotic activity and a well-differentiated angiosarcoma localized to the spleen and invading lymph nodes.

CONCLUSIONS

We speculated that the angiosarcoma and duodenal gastrointestinal stromal tumors of this patient were due to the treatment of Hodgkin lymphoma with radiotherapy 30 years ago. Pancreas-preserving segmental duodenectomy can be used to treat non-malignant neoplasms of the duodenum and avoid extensive surgery. Splenectomy is the treatment of choice for localized angiosarcomas but a strict follow-up is mandatory because of the possibility of recurrence.

Adjuvant treatment of GIST: patient selection and treatment strategies

Tyrosine kinase inhibitors that target the key molecular drivers of gastrointestinal stromal tumour (GIST) are effective treatments of advanced-stage GIST. Yet, most of these patients succumb to the disease. Approximately 60% of patients with GIST are cured by surgery, and these individuals can be identified by risk stratification schemes based on tumour size, mitosis count and site, and assessment of rupture. Two large randomized trials have evaluated imatinib as adjuvant treatment for operable, KIT-positive GIST; adjuvant imatinib substantially improved time to recurrence. One of these trials reported that 3 years of adjuvant imatinib improves overall survival of patients who have a high estimated risk for recurrence of GIST compared with 1 year of imatinib. The optimal adjuvant strategy remains unknown and some patients might benefit from longer than 3 years of imatinib treatment. However, a strategy that involves GIST risk assessment following surgery using a validated scheme, administration of adjuvant imatinib for 3 years, patient monitoring during and after completion of imatinib to detect recurrence early, and reinstitution of imatinib if GIST recurs is a reasonable choice for care of patients with high-risk GIST.

Gastrointestinal stromal tumors

INTRODUCTION

The gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the intestinal tract, known to be refractory to conventional chemotherapy or radiation. Its pathogenesis is defined by mutations within the KIT and PDGFRA gene, which constitutively activate KIT and PDGFRA oncoproteins, and serve as crucial diagnostic and therapeutic targets.

DISCUSSION

Besides surgery, therapy with imatinib mesylate, which inhibits KIT kinase activity, represents the other cornerstone for the treatment of GIST. Still, the only curative option for GIST is given after complete surgical removal even in a metastatic setting, but recurrence is common, and the risk can be defined by surgical factors like incomplete resection, intraperitoneal rupture, or bleeding and tumor associated factors like tumor size, mitotic index, or localization.

CONCLUSION

Consequently, adjuvant therapy with imatinib mesylate or other tyrosine kinase inhibitors is recommended for high-risk patients after complete resection. For unresectable and advanced GIST, a partial response or stable disease can be achieved in about 80% of patients with imatinib mesylate.

Histopathology of gastrointestinal stromal tumor

Gastrointestinal stromal tumor (GIST), generally driven by oncogenic KIT or PDGFRA mutations, is the most common mesenchymal tumor of the gastrointestinal (GI) tract. GIST is most common in the stomach (60%) and small intestine (30%), but can occur anywhere in the GI-tract and the intra-abdominal soft tissues. GIST can show spindle cell or epithelioid morphology, and mitotic count and tumor size are most important prognostic parameters. GISTs in NF1 patients and children are distinctive clinicopathologic groups. Immunohistochemical testing for KIT and sometimes for DOG1/Ano 1 is essential in confirming the diagnosis.

Morphology of gastrointestinal stromal tumors: historical perspectives

About 2/3 of gastrointestinal stromal tumors occur in the stomach and about 1/5 in the small intestine with few in the rectum, colon, and esophagus. Their cells are related to the interstitial cells of Cajal. They differ by site in terms of cell type and growth pattern. Benign and malignant tumors are separated based on their light microscopic appearances, size as measured by innumerable pathologists and assistants and mitotic counts.

Gastrointestinal stromal tumours: origin and molecular oncology

Gastrointestinal stromal tumours (GISTs) are a paradigm for the development of personalized treatment for cancer patients. The nearly simultaneous discovery of a biomarker that is reflective of their origin and the presence of gain-of-function kinase mutations in these tumours set the stage for more accurate diagnosis and the development of kinase inhibitor therapy. Subsequent studies of genotype and phenotype have led to a molecular classification of GIST and to treatment optimization on the basis of molecular subtype. The study of drug-resistant tumours has advanced our understanding of kinase biology, enabling the development of novel kinase inhibitors. Further improvements in GIST treatment may require targeting GIST stem cell populations and/or additional genomic events.

Gastrointestinal stromal tumors of the stomach and duodenum

PURPOSE OF REVIEW

Gastrointestinal stromal tumors (GISTs) are rare, malignant neoplasms of the gastrointestinal tract which are in most cases driven by oncogenic mutation of KIT or PDGFRA. GISTs may arise anywhere along the gastrointestinal tract but the stomach is the most common primary location, whereas duodenal GISTs are rare. New data regarding the adjuvant treatment of these tumors were recently reported and are likely to impact patient management.

RECENT FINDINGS

In this article, we review the diagnostic, prognostic and therapeutic specificities of gastric and duodenal GISTs. Also, specificities in the molecular biology of gastric and duodenal GISTs are discussed.

SUMMARY

Gastric GISTs are relatively frequent and recent data indicate that imatinib-resistant PDGFRA-D842V mutation may be found in up to 10% of cases of localized gastric GISTs and this impacts the prescription of adjuvant imatinib. Duodenal GISTs, on the contrary, are rare and have rather poor prognosis. Furthermore these tumors frequently harbor KIT exon 9 mutations for which the adequate dose of adjuvant imatinib is debated.

A large gastrointestinal stromal tumor of the duodenum: a case report

Introduction

Gastrointestinal stromal tumors of the duodenum are uncommon. They can reach a large size. Diagnosis can be elusive and managing them can be difficult. Our case report aims to increase awareness and highlight some issues related to the diagnosis and management of duodenal gastrointestinal stromal tumors.

Case presentation

We present the case of a 38-year-old Middle Eastern woman with a large, slowly-growing gastrointestinal stromal tumor of the duodenum. Her complaints were minor epigastric discomfort and swelling. A pancreaticoduodenectomy with complete tumor excision was performed. She was doing very well with no evidence of disease recurrence when she was last seen 34 months after her operation.

Conclusion

Gastrointestinal stromal tumors of the duodenum should be suspected in any patient with a duodenal wall mass. Extramural growth and central ulceration with or without bleeding should alert the endoscopist to the possibility of a duodenal gastrointestinal stromal tumor diagnosis. There is more than one surgical approach available; however, complete surgical excision, with negative margins, is the absolute requirement. Preoperative imatinib mesylate can be considered in unresectable or borderline resectable cases.

Segmental duodenectomy with duodenojejunostomy of gastrointestinal stromal tumor involving the duodenum

Duodenal gastrointestinal stromal tumors (GISTs) are uncommon and a relatively small subset of GISTs whose optimal surgical procedure has not been well defined. Because submucosal spread and local lymph node involvement is infrequent in GISTs, wide margins with routine lymph node dissection may not be required. Various techniques of limited resection for duodenal GISTs have been described depending on the site and the size of the tumors. In this study, we report two cases of GIST involving the third and fourth portion of the duodenum successfully treated by segmental duodenectomy with end-to-end duodenojejunostomy. This technique should be considered as a treatment option for GIST located at the third and fourth portion of the duodenum.

Advances in clinicopathological classification and genotyping of gastrointestinal stromal tumors

In recent years, the discovery of new markers and advances in mutation detection technologies have made it easy to diagnose gastrointestinal stromal tumor (GIST). However, it is still difficult to predict the biological behavior of GIST. Currently, the most prevalent GIST classification systems, including the National Institutes of Health (NIH) consensus criteria for assigning risk to gastrointestinal stromal tumors (2008 Revision) and the International Union Against Cancer TNM classification of malignant tumors (2010 version), are based on tumor size, mitotic rate, tumor location, and presence of a tumor rupture or not. Molecular genetic studies have shown that genotype of GIST is closely related to tumor prognosis and response to imatinib mesylate.

Different sites and prognoses of gastrointestinal stromal tumors of the stomach: report of 187 cases

BACKGROUND

The stomach is the most common site of gastrointestinal stromal tumors (GISTs), but the clinical behavior of gastric GISTs at different sites is unclear. This study was designed to evaluate the clinicopathological (CP) parameters and influence of different gastric sites on outcome in patients with GIST.

METHODS

The CP and follow-up records of 187 patients with GIST who were treated at TianJin Medical University Cancer Institute & Hospital between January 1985 and December 2006 were reviewed. There were 97 men and 90 women (aged 17-88 (median, 56.5) years). CP factors were assessed for overall survival (OS) by using univariate and multivariate analysis.

RESULTS

The numbers of cases of upper, middle, and lower third gastric GISTs were 69 (36.9%), 103 (55.1%), and 15 (8%), respectively. Sites of GISTs in the middle or upper stomach, tumor size, intermediate- or high-risk groups, high mitotic count, and low resection status were associated with poor OS (p = 0.041, 0.046, 0.006, 0.000, 0.000, respectively) in a univariate analysis. In a multivariate analysis, tumor location in the upper and middle third of the stomach (p = 0.035), an intermediate or high risk (p = 0.01), and incomplete resection status (p = 0.006) were predictive of poor OS.

CONCLUSIONS

Patients in intermediate- and high-risk groups had an unfavorable outcome. A complete resection is the most important treatment for survival. The location of GIST in the lower third of the stomach may be a favorable factor, and the significance of different tumor sites for prognosis of gastric GISTs needs to be further clarified.

Colorectal gastrointestinal stromal tumor

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm arising in the digestive tract, with an estimated prevalence of 15-20 per 1,000,000. GISTs are related to the interstitial cells of Cajal and are characterized by constitutive over-expression of the transmembrane tyrosine kinase receptor KIT. This is produced by a patognomonic mutation of the proto-oncogene c-kit that occurs in up to 90% of cases. Exon 11 is affected most frequently; exons 9 and 13 are less commonly involved. One-third of GISTs lacking KIT mutations exhibits alternative activating mutations in the PDGFRα gene. Colorectal GISTs represent about 5-10% of the cases, mainly located in the rectum that is the third common site. Benign GISTs are more common, but many tumors are of uncertain malignant potential; tumor size and rate of mitosis are still the most reliable criteria for assessing the risk of an aggressive behavior. Surgery is the first-line treatment for resectable non-metastatic colorectal GIST. Standard oncologic resection is inappropriate because skip metastases and lymphatic spread are rarely reported. Segmental colectomy with negative margins is recommended, and local excision is oncologically adequate in highly selected rectal tumors. Radical surgery alone is not always curative especially in high-risk GISTs, and half of patients develops local recurrences or distant metastases after R0 operation. Medical therapeutic strategies have rapidly evolved after the introduction of targeted molecular therapy. Efficacy and safety of imatinib mesylate was first demonstrated in patients with metastatic and unresectable disease. Adjuvant and neoadjuvant use of imatinib are promising therapeutic options to improve the outcome of surgery to downstage unresectable lesions and to allow less extensive resections.

Epidemiology of cancer of the small intestine

Cancer of the small intestine is very uncommon. There are 4 main histological subtypes: adenocarcinomas, carcinoid tumors, lymphoma and sarcoma. The incidence of small intestine cancer has increased over the past several decades with a four-fold increase for carcinoid tumors, less dramatic rises for adenocarcinoma and lymphoma and stable sarcoma rates. Very little is known about its etiology. An increased risk has been noted for individuals with Crohn’s disease, celiac disease, adenoma, familial adenomatous polyposis and Peutz-Jeghers syndrome. Several behavioral risk factors including consumption of red or smoked meat, saturated fat, obesity and smoking have been suggested. The prognosis for carcinomas of the small intestine cancer is poor (5 years relative survival < 30%), better for lymphomas and sarcomas, and best for carcinoid tumors. There has been no significant change in long-term survival rates for any of the 4 histological subtypes. Currently, with the possible exceptions of obesity and cigarette smoking, there are no established modifiable risk factors which might provide the foundation for a prevention program aimed at reducing the incidence and mortality of cancers of the small intestine. More research with better quality and sufficient statistical power is needed to get better understanding of the etiology and biology of this cancer. In addition, more studies should be done to assess not only exposures of interest, but also host susceptibility.

Surgical options for localized and advanced gastrointestinal stromal tumors

The development of imitinab has led to a revolution in the management of gastrointestinal stromal tumors (GIST), but surgical resection remains the cornerstone of treatment for patients with localized disease. The principles to surgical treatment of GIST include careful handling of tissues to prevent tumor rupture and resection to negative margins without the need for wide excision. Minimally invasive techniques have proven equally efficacious provided appropriate oncologic resections are performed.

Gastrointestinal Mesenchymal Neoplasms other than Gastrointestinal Stromal Tumors: Focusing on Their Molecular Aspects

Gastrointestinal (GI) mesenchymal tumors other than gastrointestinal stromal tumor (GIST) are rare neoplasms, but they often enter the differential diagnosis of more common GI lesions. Some of these mesenchymal tumors in the GI tract have well understood molecular pathologic aspects, including desmoid tumors, inflammatory myofibroblastic tumor (IMT), clear cell sarcoma (CCS), inflammatory fibroid polyp (IFP), and synovial sarcoma (SS). Molecular pathology is fast becoming a mainstream focus in laboratories because it aids in the precise classification of tumors, may be prognostic, and may help predict response to therapy. The following review is not intended as an exhaustive summary of all mesenchymal tumors that have been reported to involve the GI tract, but instead will highlight the current knowledge of the most important non-GIST GI mesenchymal neoplasms, focusing on those tumors with well-characterized molecular pathology and how the molecular pathologic features impact current diagnostic, therapeutic, and prognostic standards.

Gastrointestinal Stromal Tumor in a Patient with Neurofibromatosis: Abscess Formation in the Tumor Leading to Bacteremia and Seizure

A 66-year-old woman with neurofibromatosis type 1 (NF1) was brought to the emergency room with seizures and high-grade fever. Seizure in adult NF1 patients raises concern for intracranial lesions. However, neurological examination and central nervous system imaging failed to detect any causative intracranial lesions for her seizure. Gram-positive cocci, Streptococcus anginosus, were detected by blood cultures. Abdominal computed tomography revealed a well-defined round mass 7 cm in diameter, which was found to be a small intestinal gastrointestinal stromal tumor (GIST) containing an abscess. There was fistula formation between the intestinal lumen and the abscess, in which there were numerous Gram-positive cocci. The seizure may have been caused by hypoosmolality (hyponatremia and hypoproteinemia), which may result from decreased food intake associated with high-grade fever and general malaise. In this case GIST originating from the small intestine was invaded by S. anginosus through a fistula, leading to abscess formation, bacteremia, high-grade fever, and seizure, which was the first clinical manifestation.

Robot-assisted oncologic resection for large gastric gastrointestinal stromal tumor: a preliminary case series

BACKGROUND

Laparoscopic resection of gastric gastrointestinal stromal tumor (GIST) has been shown as feasible and safe in terms of oncologic results. However, laparoscopic resection has been demonstrated to be mainly suitable for small, favorably localized GIST. The robotic approach may, by its characteristics, enable the surgeon to perform atypical gastrectomies in an unfavorable location (i.e., close to pylorus or cardia). Its use in oncologic gastric surgery has been poorly defined and has never been reported for GIST.

MATERIALS AND METHODS

All patients who underwent robotic-assisted gastric resection for GIST at a single institution from 2006 to 2009 were prospectively followed-up.

RESULTS

There were 5 patients (3 men and 2 women), with a median age of 39 years (range, 32-74), who had a complete resection (R0). Two patients had a cardial GIST and 3 of the antrum. Median tumor sizes were of 5.5 cm (range, 4.2-7). According to Fletcher criteria, 4 tumors (80%) were classified as intermediate or high risk. No postoperative morbidity and mortality were noted. One patient had a conversion to open surgery because of a suspicion of diffuse adenocarcinoma on fresh frozen section and necessitated a total gastrectomy with a radical lymph node dissection. Median operation time was 192 minutes (range, 132-285). With a median follow-up of 18 months (range, 11-27), disease-free survival rate was 100%.

CONCLUSIONS

The da Vinci robot (Intuitive Surgical, Inc., Sunnyvale, CA) is a valuable instrument for oncologically safe resection with esogastric or duodenogastric junction preservation for an unfavorably located gastric GIST. Moreover, the three-dimensional, high-definition vision, instrument mobility, and ease of performing a difficult suturing enable a safe, large atypical gastrectomy, close to the pylorus or cardia.

Duodenal gastrointestinal stromal tumor resembling a pancreatic neuroendocrine tumor in a patient with neurofibromatosis type I (von Recklinghausen's disease): a case report

Introduction

Gastrointestinal stromal tumor is the most frequent nonepithelial tumor found in the gastrointestinal tract. One important clinical problem is that gastrointestinal stromal tumors, especially the extramural growth type, can be difficult to distinguish from other organ tumors. The case of a patient with an extramural gastrointestinal stromal tumor of the duodenum that mimicked a pancreatic head tumor has previously been reported. Here, we report a rare case of a patient with a duodenal gastrointestinal stromal tumor with extramural growth that mimicked a pancreatic neuroendocrine tumor. In this case, the gastrointestinal stromal tumor was also associated with neurofibromatosis type 1 (also known as von Recklinghausen's disease). To the best of our knowledge, this is the first report to describe the case of a patient with a duodenal gastrointestinal stromal tumor with neurofibromatosis type 1 in which the radiological findings resembled those of a pancreatic neuroendocrine tumor.

Case presentation

A 60-year-old Japanese woman with a history of neurofibromatosis type 1 was admitted to our hospital for the treatment of a tumor of her pancreas. She had no symptoms, but an abdominal ultrasonography screening examination had revealed a hypoechoic mass in the head of her pancreas. Laboratory data, including tumor markers, were within the normal ranges, and her insulin and glucagon levels were also within the normal ranges. However, her plasma gastrin level was elevated at 580 pg/mL (30 to 150 pg/mL). A computed tomography examination revealed a hypervascular tumor measuring 14 mm in diameter in the head of her pancreas. We diagnosed the patient as having a pancreatic neuroendocrine tumor and performed a tumor resection with a duodenal wedge resection. Microscopic analysis revealed spindle cell tumors in a trabecular pattern. The patient was finally diagnosed as having a duodenal gastrointestinal stromal tumor of the uncommitted type.

Conclusion

Extramural growth-type gastrointestinal stromal tumors can be difficult to distinguish from other organ tumors. In our case, a duodenal gastrointestinal stromal tumor was difficult to distinguish from a pancreatic neuroendocrine tumor based on radiological findings. When patients are identified as having hypervascular lesions that have adhered to the gastrointestinal tract, the possibility of an extramural growth-type gastrointestinal stromal tumor as a differential diagnosis should be considered in patients with neurofibromatosis type 1.

Occurrence of other tumors in patients with GIST

OBJECTIVE

Evaluate the presence of other tumors in cohort of patients with GIST treated at a cancer treatment referral center - INCA.

METHODS

We reviewed the medical records of patients diagnosed with GIST who were treated at INCA between 1998 and 2008. Immunohistological diagnosis was confirmed by a pathologist specialized in sarcomas. Patients presenting second non-GIST tumors were identified. Age, sex, tumor location, risk groups (according to the National Institutes of Health criteria), characteristics of non-GIST tumors and treatment results were analyzed.

RESULTS

Among the 101 patients diagnosed with GIST who were evaluated during the study period, 14 (13.8%) had other non-GIST tumors, 9 females (64.3%), with a median age of 68 years (10-79 years). The stomach was the location of GISTs in 8 cases (57.1%), followed by the small bowel in 4 cases (28.5%), colon and mesentery with 1 case (7.1%) each. The mean size of lesions was 4.79 cm (0.3-15 cm), with malignant potential low/very low in 7 cases (50%), intermediate in 5 cases (35.7%) and high in 2 cases (14.3%). The diagnosis of GIST was incidental in 6 cases and in one case the non-GIST tumor was incidental. The non-GIST tumors were most frequent in the stomach (adenocarcinoma), in 4 cases (28.5%) and colon/rectum (adenocarcinoma) in 4 other cases. The other sites involved were breast (ductal carcinoma), kidney (clear cell carcinoma), prostate (adenocarcinoma), endometrium (adenocarcinoma), ovary (adenocarcinoma) and adrenal (neuroblastoma), with one case each. The tumors were synchronous in 7 cases (50%). With a median follow-up after GIST resection of 41 months (2-87 months), 9 patients were alive without evidence of disease, 2 died due to GIST, 2 died due to non-GIST tumors and the remaining patient died due to postoperative complications.

CONCLUSIONS

We discovered a 13.8% incidence of non-GIST tumors in a series of 101 GIST cases under our care. This association should always be considered in the management of patients with GIST.

Endoscopic resection of small gastrointestinal stromal tumors

BACKGROUND

The common treatment principle of gastrointestinal stromal tumors (GISTs) is complete resection of the tumor. The rapid development of endoscopic skill makes it possible to resect GISTs en-bloc through the endoscopic approach.

AIMS

The aim of this study is to evaluate the feasibility of endoscopic resection for small-size (<30 mm) gastric GISTs.

METHODS

A total of 25 patients with gastric GISTs underwent endoscopic resection assisted with needle knife, loop, and snare. Clinical data, perioperative outcomes, tumor size and microscopic characteristics, immunohistochemical staining results, and follow-up outcomes were recorded.

RESULTS

Endoscopic resection was successfully accomplished in 25 patients at age of 56.72 +/- 11.42 years. The average operation time was 58.52 +/- 21.84 min. Perforation for 2-6 mm occurred in seven patients (28%) and was closed well with clips, with no conversions to open surgery. No mortalities occurred. All tumors were located in the stomach, and had an average size of (11.64 +/- 6.12) mm (5-30 mm). The average length of hospitalization was 4.28 +/- 0.84 days. Out of the total of 25 patients, 21 (84%) were at very low risk and only one (4%) was at intermediate risk. Positive rate of CD117 and CD34 was 92 and 84%, respectively. A follow-up for 11.44 +/- 5.79 months (2-23 months) showed no recurrence or metastasis.

CONCLUSIONS

Endoscopic resection is feasible, safe, and effective for small-size gastric GISTs (<30 mm). Short-term follow-up evaluation merits favorable clinical results.