title: Coexistence of gastrointestinal stromal tumors and gastric adenocarcinomas.
abstract: The purpose of this study is to detect the clinicopathology of gastrointestinal stromal tumors (GISTs) occurring synchronously with gastric adenocarcinomas and to unveil the potential underlying relationship between the synchronous GIST and gastric adenocarcinoma. This study included 15 patients with incidental GISTs found during operations for gastric adenocarcinoma and 30 patients who underwent gastrectomy for gastric cancer without discovering GIST between January 2005 and December 2010 at the Beijing Cancer Institute. We collected the clinicopathological data and analyzed the KIT/PDGFRA mutational status of GISTs, corresponding gastric adenocarcinoma specimens, and the normal tissue around the cancer lesions. Additionally, as a control group, the mutational status of the patients with gastric adenocarcinoma and no other tumors was assayed. Overall, 18 GISTs were found in 15 gastric adenocarcinoma patients. Multiple GIST lesions were found in three cases (20 %). The patients' age ranged from 46 to 85 years, with an average of 67.6 years. The average size of the GISTs was 0.85 cm. All mesenchymal lesions showed low proliferative activity, were of low or very low risk, and were identified as CD117-positive by immunostaining. In GIST lesions, mutations in KIT were detected in 7 out of 13 cases, and of these mutations, 6 were found in exon 11 (46.2 %), and 1 was found in exon 9 (7.7 %). A total of five deletions and one point mutation were in exon 11, and one insertion was in exon 9. Mutations were not detected in exon 17 or 13 of KIT. There was no remarkable mutation analyzed in the gastric adenocarcinoma lesions or normal tissues from either the test or control groups. Clinicopathological profiles and molecular analysis of KIT/PDGFRA showed no obvious relationship between gastric cancer and GISTs in tumor genesis, such as similar oncogene mutations.
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Surgery, Beijing Cancer Hospital and Institute, Peking University School of Oncology, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.forename: Ziyu
authors.initials: Z
authors.lastname: Li
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Liu
authors.forename: Lianhai
authors.initials: L
authors.lastname: Zhang
authors.forename: Jiyou
authors.initials: J
authors.lastname: Li
authors.forename: Jiafu
authors.initials: J
authors.lastname: Ji
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D046152:Gastrointestinal Stromal Tumors / Q000235:genetics / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009378:Neoplasms, Multiple Primary / Q000235:genetics / Q000473:pathology*; D011379:Prognosis; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics*; D013274:Stomach Neoplasms / Q000235:genetics / Q000473:pathology*
chemical_list: D014408:Biomarkers, Tumor; D019009:Proto-Oncogene Proteins c-kit; D020796:Receptor, Platelet-Derived Growth Factor alpha