title: [Staging and histologic grading of gastrointestinal stromal tumors].
abstract: OBJECTIVE
  To investigate the clinical stage and histological grade of gastrointestinal stromal tumors.
  
  
  METHODS
  Twelve clinical and pathological parameters were assessed in 613 patients with follow-up information. These parameters were classified into two gross spread parameters including liver metastasis and peritoneal dissemination, five microscopic spread parameters including lymph node metastasis, vascular, fat, nerve and mucosal infiltration, and five histological parameters including mitotic count ≥ 10 per 50 high-power fields, muscularis propria infiltration, coagulative necrosis, perivascular pattern and severe nuclear atypia.
  
  
  RESULTS
  The accumulated 5-year disease-free survival (DFS) and overall survival (OS) of 293 patients without any of these predictive parameters of malignancy were 99.3% and 100.0%, respectively. They were regarded as nonmalignant and further evaluations on the stage and grade of these tumors were not performed. At least one and at most seven predictive parameters of malignancy were identified in 320 patients. For these patients, the accumulated 5-year DFS and OS rates were 43.9% (mean 6.7 years) and 59.7% (mean 9.3 years), respectively. The DFS showed significant difference between patients with and without gross spread (P < 0.01), with and without microscopic spread (P = 0.001). DFS and OS were associated with the number of predictive parameters of malignancy in patients without gross spread (P < 0.01 for both DFS and OS), but not in patients with gross spread (P = 0.882 and 0.441, respectively).
  
  
  CONCLUSIONS
  Malignant GIST could be divided into clinical stages I and II based on the absence and presence of gross spread, respectively. The degree of malignancy of patients in clinical stage I could be graded according to the number of predictive parameters of malignancy. Patients in clinical stage II were of the highest degree of malignancy regardless of the number of parameters. The staging and grading of gastrointestinal stromal tumors in this study are strongly associated with prognosis.
authors: Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai 200032, China.
authors: De-ming
authors: DM
authors: He
authors: Yuan
authors: Y
authors: Shi
authors: Ying-yong
authors: YY
authors: Hou
authors: Jun
authors: J
authors: Hou
authors: Shao-hua
authors: SH
authors: Lu
authors: Ya-lan
authors: YL
authors: Liu
authors: Chen
authors: C
authors: Xu
authors: Qin
authors: Q
authors: Hu
authors: Yun-shan
authors: YS
authors: Tan
authors: Xiong-zeng
authors: XZ
authors: Zhu
mesh_terms: D000199:Actins / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018952:Antigens, CD34 / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D046152:Gastrointestinal Stromal Tumors / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading / Q000379:methods*; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging / Q000379:methods*; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism; D015996:Survival Rate; D055815:Young Adult
chemical_list: C541116:ACTA2 protein, human; D000199:Actins; D018952:Antigens, CD34; D019009:Proto-Oncogene Proteins c-kit