Gastrointestinal stromal tumors/smooth muscle tumors (GISTs) primary in the omentum and mesentery: clinicopathologic and immunohistochemical study of 26 cases.

Gastrointestinal stromal tumor or smooth muscle tumor (GIST) is the designation for a major subset of gastrointestinal mesenchymal tumors that histologically, immunohistochemically, and genetically differ from typical leiomyomas, leiomyosarcomas, and schwannomas. Because GISTs, like the interstitial cells of Cajal, the gastrointestinal pacemaker cells, express CD117 (c-kit protein), the origin of GISTs from the interstitial cells of Cajal has been recently proposed. Comparison of GISTs primary in the omentum and mesentery to GISTs primary in the tubular gastrointestinal tract is of particular diagnostic and histogenetic interest in view of the possible similarity of these tumors with the GIST group. In this study, we analyzed 14 omental and 12 mesenteric primary mesenchymal tumors representing smooth muscle tumors or GISTs. These tumors were phenotypically compared with gastric and small intestinal GISTs, leiomyomas of the esophagus, and leiomyosarcomas of the retroperitoneum. Most (13 of 14) omental and mesenteric (10 of 12) tumors showed histologic features similar to GISTs with elongated spindle cells or epithelioid cells with high cellularity; most of these tumors showed low mitotic activity. Omental and mesenteric GISTs were typically positive for CD117 and less consistently for CD34. They often showed alpha-smooth muscle actin reactivity but were virtually negative for desmin and S-100 protein. One omental and two mesenteric tumors showed features of leiomyosarcoma with ovoid, less elongated nuclei, cytoplasmic eosinophilia; all these tumors had significant mitotic activity. These tumors were positive for alpha-smooth muscle actin and two of them for desmin, but all were negative for CD34 and CD117, similar to retroperitoneal leiomyosarcomas. Tumor-related mortality occurred in the group of mesenteric GISTs, but not in the group of omental GISTs. In contrast, all three patients with a true leiomyosarcoma of the omentum or mesentery had documented liver metastases or died of tumor. In summary, we show that tumors phenotypically identical with GISTs occur as primary tumors in the omentum and mesentery. The occurrence of CD117-positive tumors outside the gastrointestinal tract militates against an origin of these tumors exclusively from the interstitial cells of Cajal.     

Exophytic gastrointestinal stromal tumor of the stomach. Report of two cases

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. Most GISTs occur in the stomach (60-70%). Their diagnosis is established immunohistochemically and reveals that the tumor cells are immunoreactive for the antigens CD117 and CD34. The infiltration of the adjacent organs, the large tumor size (>5cm) and the mitosis count of the cells (>5/50 CHPFs) are typical characteristics of GIST malignancy. GISTs rarely infiltrate adjacent organs and usually push them back. The clinical behaviour of GISTs is highly variable and tumor size mitotic rate and location are prognostic determinants.The biologic behaviour of GIST is variable. The majority were previously thought to be benign due to their characteristically bland histopathologic features. However, it is becoming increasingly clear that with long follow-up, virtually all GISTs have the potential for malignant behaviour, even those 2 cm or less with bland histologic features. Thus, it is not appropriate to define any GIST as "benign" per se.We present two cases of exophytic gastric GIST which were recently treated successfully in our Clinic with “wedge” gastric resection. The margins were negative and there was neither rupture of the tumor, nor spillage.     

Gastrointestinal stromal tumors of the jejunum and ileum: a clinicopathologic, immunohistochemical, and molecular genetic study of 906 cases before imatinib with long-term follow-up

Gastrointestinal (GI) stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are the most common mesenchymal tumors of the GI tract. This study analyzed 1091 tumors originally classified as smooth muscle tumors of the small intestine (including jejunum or ileum and excluding duodenum), and found that 906 (83%) of these were GISTs. The GIST patients had 55:45 male-to-female ratio with a median age of 59 years (range, 13-94 years). Only 0.6% of tumors occurred before the age of 21 years and 13.6% before the age of 40 years. The tumors varied from 0.3 to 40 cm (median, 7.0 cm) and most commonly presented with GI bleeding or acute abdomen; 18% were incidentally detected. Histologically, the tumors were relatively monotypic with spindle cell (86%), epithelioid (5%), or mixed patterns (9%). Skeinoid fibers were present in 44% of cases, and their presence was associated with a favorable course. Most epithelioid tumors were malignant, and this morphology sometimes emerged from less cellular and less mitotically active spindle cell tumors, suggesting that it represented a transformation. KIT was immunohistochemically detected in 98%, CD34 in 40%, smooth muscle actin in 34%, desmin in 0.2%, and S-100 protein in 14% of the tumors tested. Outcome was strongly dependent on tumor size and mitotic activity, with an overall 39% tumor-related mortality, twice that for gastric GISTs. Only <3% of tumors <5 cm and < or = 5 mitoses/50 HPF metastasized, whereas 86% of tumors >10 cm and >5 mitoses/50 HPF metastasized. In stark contrast to corresponding gastric tumors, tumors >10 cm with mitotic activity < or = 5/50 HPF and those < or = 5 cm with mitoses >5/50 HPF had a high metastatic rate (>50%); tumors >5 cm < or = 10 cm with low mitotic rate had a 24% metastatic rate. The median survival times of patients with low mitotic rate tumors who died of disease decreased by increasing tumor size. KIT exon 11 mutations were detected in 90 cases, exon 9 mutation in 17 cases, and exon 17 mutation in 1 case; the presence of mutation or mutation type was not prognostically significant. There were no PDGFRA exon 12 or 8 mutations. Systematic data on prognosis of small intestinal GISTs of various size and mitotic activity categories can be helpful in management and surveillance of patients with these tumors.     

Gastrointestinal stromal tumors in patients with neurofibromatosis 1: a clinicopathologic and molecular genetic study of 45 cases

Gastrointestinal stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, most commonly occur sporadically, but there seems to be some increased tendency for these tumors to develop in patients with neurofibromatosis 1 (NF1). The clinicopathologic profile, KIT, and PDGFRA mutation status and long-term prognosis of patients with GIST in NF1 are incompletely characterized. In this study, we analyzed 45 patients who had NF1 and GIST. There were 26 females and 19 males with a median age of 49 years (10 years lower than the median age of GIST patients in general). A great majority of tumors occurred in the jejunum or ileum, with multiple tumors occurring in 28 cases. Ten patients had a duodenal and one had a gastric GIST. The most common presentations were gastrointestinal bleeding and anemia, and many patients had intermittent bleeding over several years. The majority of the tumors were small and mitotically inactive; only 7 had mitotic activity >5/50 HPFs and 15 tumors were >5 cm. Associated Cajal cell hyperplasia was common. One patient had an intraabdominal peri-intestinal neurofibroma. Five of 35 patients with follow-up died of metastatic disease; all of these had a tumor >5 cm, mitotic rate >5/50 HPFs, or both; three of these tumors were located in the duodenum. The presence of multiple small tumors was not associated with progressive disease. Most patients with long-term follow-up enjoyed a good prognosis; 2 died of other NF1-associated tumors (malignant peripheral nerve sheath tumors, brain tumor). None of the 16 tumors from 15 patients had a KIT exon 9, 11, 13, or 17 or PDGFRA exon 12 or 18 mutation as is typically seen in sporadic GISTs, indicating that GISTs in NF1 patients have a different pathogenesis than sporadic GISTs.     

Clinicopathological and Immunohistochemical Features of Extragastrointestinal Stromal Tumors: Report of Two Cases

CD117 (c-kit proto-oncogene protein product) is expressed in most gastrointestinal stromal tumors (GISTs) and plays a crucial role in the pathogenesis and treatment of this disease. However, the clinicopathological and immunohistochemical features of CD117-positive mesenchymal tumors without connection to the gastrointestinal tract, known as extragastrointestinal stromal tumors (EGISTs), are not well documented because these tumors are rare. We describe the clinicopathological and immunohistochemical features of two cases of EGIST and compare them with those of GIST. Of the 1855 abdominal or esophageal tumors resected during the past 10 years at our hospital, 23 were GISTs and 2 were EGISTs. The clinicopathological or immunohistochemical characteristics do not seem to differ remarkably between EGISTs and GISTs. Although rare, CD117 positivity should be tested in abdominal mesenchymal tumors that have no connection to the gastrointestinal tract. The clinicopathological features of CD117-positive abdominal mesenchymal tumors may not depend on whether the tumor is connected to the gastrointestinal tract.     

Gastrointestinal stromal tumors

Gastrointestinal stromal tumor (GIST) account for 1% of all gastrointestinal neoplasms and are the most common mesenchymal tumor of gastrointestinal tract. There are considered to originate fom the intestinal cell of Cajal, an intestinal pacemaker cell, characterized usually express the KIT protein on immunohistochemistry. The stomach (40-60%) and small intestine (30-40%) are the most common locations. Diagnosis of these tumors is difficult to establish, because symptoms are vague and traditional diagnostic tests are not specific. GISTs shows a wide variety of clinical behaviours ranging fom benign to frankly malignant, making the outcome totally unpredictable. Surgery is the standard treatment of local GIST while Imatinib (tyrosine kinasi inhibitor) is considered as the standard treatment of metastatic disease. Resistence to Imatinib is also becoming a major clinical problem but new tirosyne kinase inibitor are being studied to improve the treatment and survival. The present paper is a review of the salient features of epidemiology, pathophysiology, diagnosis, therapy and prognostic factors of GIST     

Stromal tumors of the small intestine: personal experience and review of the literature

Malignant gastointestinal stromal tumors (M-GIST) are rare mesenchymal tumors that arise in the wall of the gastrointestinal (GI) tract. Small intestinal GIST account for approximately 35% of all GIST the diagnosis of these tumors is difficult to establish, because the symptoms are vague and non-specific and traditional endoscopy is commonly unsatisfactory. Because of the infrequent nature of malignant small bowel tumors, the natural history and factors affecting outcome remain poorly defined; stage at presentation and complete surgical resection seem to be the main prognostic factors. For these rare tumors, surgery remains the treatment of choice, with little efficacy reported for irradiation, chemiotherapy, or both. Two cases of GIST of the jejunum, complicated by intestinal bleeding and intestinal obstruction respectively, are presented and a review of the literature is made.     

Gastrointestinal Stromal Tumors: Current Diagnosis, Biologic Behavior, and Management

Gastrointestinal stromal tumors (GIST) are rare tumors of the gastrointestinal (GI) tract that arise from primitive mesenchymal cells. GISTs occur throughout the GI tract but are usually located in the stomach and small intestine. The majority of GISTs are immunohistochemically positive for c-kit protein (CD117) and CD34. GISTs express a heterogeneous clinical course not easily predicted by standard pathological means. The most important prognostic factors are size >5 cm, tumor necrosis, infiltration and metastasis to other sites, mitotic count >1–5 per 10 high-powered fields, and most recently, mutation in the c-kit gene. Surgical resection remains the mainstay of treatment, as chemotherapy and radiation are ineffective. Long-term follow-up is imperative, as recurrence rates are high.     

Laparoscopic approach of gastric gastrointestinal stromal tumors (GISTs): is it still a courageous choice? Report of two cases

Gastrointestinal stromal tumors (GISTs) are a well-defined clinicopathologic and molecular tumor entity, representing the most common gastrointestinal mesenchymal neoplasm. Differential diagnosis between GIST and other mesenchymal malignancies is crucial, given the successful management using targeted therapy in metastatic GIST. The mainstay of treatment remains surgery, complete tumor resection being the most important independent prognostic factor. Videolaparoscopic approach is still controversial for the high risk of tumor rupture or bleeding. Here we report 2 cases of GIST surgically resected using a videolaparoscopic approach and discuss the efficacy of this technique in selected patients.     

Gastrointestinal stromal tumors of the stomach in children and young adults: a clinicopathologic, immunohistochemical, and molecular genetic study of 44 cases with long-term follow-up and review of the literature

Gastrointestinal stromal tumors (GISTs), specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are rare in children and young adults, and their clinicopathologic and molecular genetic profile is incompletely understood. In this study, we analyzed 44 gastric GISTs occurring by the age of 21 years. There were 32 females and 12 males, youngest of whom were a 5-year-old boy and an 8-year-old girl. All but 1 of 25 patients under the age of 16 were girls. The patients most commonly received medical attention because of chronic, insidious gastrointestinal bleeding with anemia, less commonly with acute GI bleeding. Only 1 patient had Carney triad with pulmonary chondroma. None of the patients had family members with GIST. The tumors measured from 1.5 to 24 cm (median, 5.6 cm). A total of 21 tumors with specified location were in the antrum and 8 were in the gastric body. Histologically, 26 tumors were composed of epithelioid cells, 12 of spindle cells, and 6 of combination thereof. Mitotic activity varied form 0 to 65/50 HPF (median, 5/50). All but one of the 24 tumors tested were KIT-positive, and 20 were CD34-positive. Eleven patients developed liver or abdominal metastases, and 6 of them died of tumor surviving 5.5 to 35.5 years (median, 16 years) after the first surgery; three of these tumors had a low mitotic activity and size <10 cm. Twenty-one patients were alive with no evidence for disease 7 to 41 years (median, 17 years) after the first surgery. None of the 13 tumors examined (7 of them 8- to 16-year-old females) had KIT exon 9, 11, 13, or 17 or PDGFRA exon 12 or 18 mutation as typically seen in adult GISTs. Gastric GISTs in children have mainly epithelioid morphology, often occur in antrum, and have a somewhat unpredictable but slow course of disease. Their pathogenesis may differ from that of adult GISTs because no KIT or PDGFRA mutations were found; connection with Carney triad seems infrequent despite demographic and histologic similarities.     

Surgical options in the treatment of GIST of the upper portion of the stomach. Report of two cases

Gastrointestinal stromal tumors are rare neoplasms arising from mesenchymal precursor cells of the gastrointestinal tract that may differentiate towards the interstitial cells of Cajal, pacemaker cells regulating autonomous motility of G.I. tract. Grading of GIST has been proven to be as difficult as their classification. Two thirds of GISTs are located in the stomach, 20-50% in the small bowel (one third in the duodenum), and 5-15% in colon and rectum; GISTs, however, may rarely be found also in the oesophagus, omentum, mesentery or the retroperitoneum. The distribuition of these tumors in the stomach is: pars media, 40%; antrum, 25%; pylorus, 20%; in less than 15%, GISTs location is next to the EGJ, in the cardia and in the iundus. The upper gastric third location of GISTs is not common, so their surgical management has been not yet well investigated. Total gastrectomy is considered the therapy of choice for the GIST located next to the EGJ, but wedge resection could be considered a surgical option in selected cases. The Authors describe 2 cases of GIST located just under the upper portion of the stomach and discuss about the different surgical options for GISTs of this region.     

Gastrointestinal stromal tumors. A case of small intestine stromal tumor (SIST) with an uncertain biological aspect

Tumors of the small intestine are relatively rare. The diagnosis is difficult to establish because the symptoms are vague and non-specific. Although the small intestine constitutes 75% of the length and over 90% of the mucosal surface area of the gastrointestinal tract, only 1 to 2% of gastrointestinal malignancies occur in this segment. Metastases are usually present at the time of diagnosis. The outcome of these patients can be improved if the possibility of a malignant small bowel tumor is considered in all cases of unexplained abdominal pain or gastrointestinal bleeding, especially in younger age. Malignant tumors occur with increasing frequency in distal small bowel with a preponderance of malignant lesions in the ileum compared with the jejunum and the duodenum. Adenocarcinoma is the most common tumor of the primary malignant small bowel tumors, followed by carcinoid, lymphoma and leiomyosarcoma. Mesenchymal tumors of the gastrointestinal tract, traditionally regarded as smooth muscle tumors, have demonstrated different cellular differentiations based on immunohistochemical and ultrastructural features. Therefore the terms leiomyoma and leiomyosarcoma have been replaced by a more encompassing term, gastrointestinal stromal tumor (GIST). The majority of GISTs occurs in the stomach; stromal tumors involving the small intestine (SISTs) are far less common but seem to have greater malignant potential. The clinical a case of a small intestinal stromal tumor (SIST), localised in the jejunum and characterised by an uncertain histological aspect, is presented and a review of the literature is made.     

Transvaginal excision of a large rectal stromal tumor: an alternative

BACKGROUND: Gastrointestinal stromal tumors (GISTs), the specific kit-positive mesenchymal tumors of the gastrointestinal tract, are rarely found in the anorectum and account for only 0.1% of all colorectal tumors. The main stem of therapy remains surgical excision. The standard surgical approach for anorectal GISTs includes transanal resection or enucleation for smaller and anterior or abdominoperineal resection for larger tumors. METHODS: We present an alternative, transvaginal approach for a local excision of a large rectal GIST. In our case, a 5 x 5 x 8 cm large GIST located 3 cm above the dentate line in the anterior rectal wall was removed through the vagina. RESULTS: In our experience, this approach enables a safe alternative even for larger tumors in the anterior rectal wall with a very low morbidity, sparing the patient from an unnecessary abdominoperineal resection.     

Gastrointestinal stromal tumors: analysis of clinical and pathologic factors

Gastrointestinal mesenchymal tumors have been classified as benign (leiomyoma) or malignant (leiomyosarcomas). More recently, these tumors have been termed gastrointestinal stromal tumors (GISTs). GISTs have a highly variable clinical course. This review analyzes the clinical presentation, pathologic examination, and long-term follow-up of patients with GIST. A retrospective analysis of the clinical course of patients with GIST at a single institution from 1986 to 1998 was performed. Nineteen patients with GIST (12 gastric, two duodenal, three jejunal, and two rectal) were treated. The most common clinical presentation was gastrointestinal bleed. CT scans, contrast studies, and endoscopy were used to identify a tumor mass. Diagnosis of GIST was made in only two patients preoperatively. Tumor size ranged from 0.8 to 23 cm. Histology of the tumors was variable. All patients underwent surgical resection with curative intent. Follow-up ranged from 2 to 55 months. There were two perioperative deaths. Local recurrence occurred in one patient. GISTs are uncommon. Preoperative diagnosis can be difficult, and often the diagnosis is made at the time of surgery. With complete resection of the tumor the clinical course is favorable with very few local recurrences. Therefore complete resection of the tumor is recommended.     

Gastrointestinal stromal tumors of the stomach: a clinicopathologic, immunohistochemical, and molecular genetic study of 1765 cases with long-term follow-up

Gastrointestinal (GI) stromal tumors (GISTs), the specific KIT- or PDFGRA-signaling driven mesenchymal tumors, are the most common mesenchymal tumors of the GI tract. In this study, we analyzed 1869 cases originally classified as smooth muscle tumors of the stomach and found that 1765 (94%) of these were GISTs. The GISTs had a slight male predominance (55%) with a median age of 63 years. Only 2.7% of tumors occurred before the age of 21 years and 9.1% before the age of 40 years. The tumors varied from 0.5 to 44 cm (median, 6.0 cm) and most commonly presented with GI bleeding; 12% were incidentally detected. Several histologic variants were recognized among the spindle cell tumors (sclerosing, palisaded-vacuolated, hypercellular, and sarcomatous) and of epithelioid tumors (sclerosing, dyscohesive, hypercellular, and sarcomatous). Outcome was strongly dependent on tumor size and mitotic activity. Only 2% to 3% of tumors <10 cm and <5 mitoses/50 HPFs metastasized, whereas 86% of tumors >10 cm and >5 mitoses/50 HPFs metastasized. However, tumors >10 cm with mitotic activity <5/50 HPFs and those <5 cm with mitoses >5/50 HPFs had a relatively low metastatic rate (11% and 15%). A small number of patients survived intra-abdominal metastasis up to over 20 years. Tumor location in fundus or gastroesophageal junction, coagulative necrosis, ulceration, and mucosal invasion were unfavorable factors (P <0.001), whereas tumor location in antrum was favorable (P <0.001). KIT expression was detected in 91% of the cases, CD34 in 82%, smooth muscle actin in 18%, and desmin in 5%; the latter two were favorable (P <0.001). KIT exon 11 mutations were detected in 119 cases; patients with point mutations fared better than those with deletions (P <0.01). PDGFRA exon 18 mutations (total 86 cases) were common in epithelioid GISTs and most commonly represented a D842V point mutation; none of these was prognostically significant. The above results may be helpful for setting the criteria for adjuvant treatment such as Gleevec.     

Management of gastrointestinal stromal tumors

A gastrointestinal stromal tumor (GIST) is a rare mesenchymal malignancy of the gastrointestinal (GI) tract. Malignant GISTs were first defined as a separate entity from a collection of nonepithelial malignancies of the GI tract in the 1980s and 1990s based on pathologic and clinical behavior. The discovery of activating KIT mutations as a near-uniform occurrence in these tumors greatly influenced the classification [1] and revolutionized therapeutic management of these tumors. To meet the next challenges, newer tyrosine kinase inhibitors and targeted agents are being developed with the goal of providing improved response rates or alternative therapies for patients progressing on established agents. In this article, the authors describe the management of GISTs, concentrating on surgical management and targeted therapies.     

Esophageal stromal tumors: a clinicopathologic, immunohistochemical, and molecular genetic study of 17 cases and comparison with esophageal leiomyomas and leiomyosarcomas

Although rare elsewhere in the gastrointestinal tract, leiomyomas (LMs) are the most common esophageal mesenchymal neoplasms. In contrast, gastrointestinal stromal tumors (GISTs) predominate in the stomach and intestines but have not been documented in the esophagus. This study was undertaken to determine the clinicopathologic features and frequency of esophageal GISTs compared with LMs and leiomyosarcomas (LMSs) of the esophagus. A total of 68 stromal/smooth muscle tumors from the Armed Forces Institute of Pathology and the Haartman Institute of University of Helsinki were reclassified by current histologic and immunohistochemical criteria. There were 17 GISTs, 48 LMs, and three LMSs. The esophageal GISTs occurred in 12 men and five women with a median age of 63 years (range, 49-75 years). All tumors were from the lowest third of the esophagus, and the most common complaint was dysphagia, whereas two tumors were detected incidentally. Histologically the tumors had an overall basophilic appearance and showed combinations of solid, myxoid, and perivascular collarlike patterns with a spindle cell histology in 13 patients and epithelioid histology in four patients. All tumors were positive for CD117 and for CD34, whereas two patients were also positive for alpha-smooth muscle actin (SMA) and three patients were positive for desmin. One patient showed a unique immunophenotype with coexpression of CD117, CD34, SMA, and desmin. Nine patients died of disease, including all who had a tumor larger than 10 cm, and also one patient whose tumor showed five mitoses per 50 high-power fields. In comparison, esophageal LMs (n = 48) occurred in a younger population (median age, 35 years) but, similar to the GIST group, men predominated (67%). All LMs were clinically indolent tumors with no tumor-related mortality. The LMs showed eosinophilic cytoplasm, and were positive for desmin and SMA, and negative for CD117 and CD34. All three LMSs were large high-grade tumors that showed muscle cell markers but no CD117. All patients died of disease. Esophageal GISTs showed mutations in exon 11 of c-kit as described previously in gastric and intestinal GISTs. The separation of GISTs from esophageal LMs is important diagnostically because the former group has a high risk of malignant behavior.     

Neoadjuvant imatinib in a gastrointestinal stromal tumor of the rectum: Report of a case

Gastrointestinal stromal tumors (GISTs) are rare tumors of the gastrointestinal tract, and of these, GISTs involving the rectum are uncommon. This report describes a case of effective neoadjuvant therapy for a rectal GIST expressing the c-kit gene, where a laparoscopic ultralow anterior resection was successfully performed, thus preserving the anus. A 57-year-old woman visited our hospital due to constipation and was found by a digital examination to have a soft mass on the right wall of the rectum. Computed tomography revealed an 8.0 × 5.0-cm mass with an unclear margin adjacent to the rectum. A biopsy specimen was positive for CD34 and the c-kit gene product, but it was not positive for smooth muscle actin or S-100 protein, and thus the tumor was diagnosed as GIST. An abdominoperineal resection is generally essential for large rectal GISTs; however, she refused this operation. Neoadjuvant treatment with Imatinib decreased the tumor size (4.0 × 3.5 cm) and the anus was preserved by a laparoscopic ultralow anterior resection with direct coloanal anastomosis. She had no evidence of disease for 24 months postoperatively. To preserve the anus, a rectal GIST expressing the c-kit gene is best treated with Imatinib as neoadjuvant therapy.     

Tumor size is a major determinant of recurrence in patients with resectable gastrointestinal stromal tumor

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of the gastrointestinal tract. Surgery remains the mainstay of curative treatment. Recurrence after surgery was frequent and was associated with poor prognosis. In this study, we tried to identify predictors of recurrence in resectable GISTs. METHODS: Between January 1995 and December 2005, 100 patients undergoing surgical resection for GISTs in 2 hospitals were studied. RESULTS: There were 67 gastric and 33 intestinal GISTs. Recurrence was noted in 11 patients (median follow-up of 43 months). Overall 5-year survival was 84%. Multivariate analysis demonstrated that tumor size > or = 10 cm was associated with higher recurrence rates (P = .032) and was the only independent poor prognostic factor for survival (P = .020). CONCLUSIONS: We concluded that tumor size > or = 10 cm carried both a higher risk of recurrence and worse survival in resectable GISTs and could be considered an indicator for adjuvant therapy.     

复发转移胃肠道间质瘤治疗策略

胃肠道间质瘤（GIST）的检出率逐年升高。大多数GIST可行手术切除，单纯手术后约70％～84％会出现复发转移，术后中位复发转移时间约为2年。中位生存期只有1年左右。伊马替尼应用于GIST治疗可延长至5年。然而，约一半以上的复发转移GIST患者应用药物半年以上后最终出现耐药，故如何合理安排此类患者治疗模式成为当前最迫切的需求。本文从复发转移GIST患者的评估、合理用药、手术干预、药物治疗失败后补救措施、患者依从性管理等方面介绍治疗策略。