Malignant degree of gastrointestinal stromal tumor and the impact on biological behavior

Abstract：Tumor stage and grade for gastrointestinal stromal tumors are undetermined. Twelve 12 clinical and pathological parameters were identified. The parameters are classified into two gross spread parameters including liver metastasis and peritoneal dissemination, five microscopic spread parameters including lymph node metastasis, vascular, fat, nerve and mu-cosal infiltration, and five histological parameters including mi-totic count > or =10 per 50 high-power fields, muscularis pro-pria infiltration, coagulative necrosis, Chinese-ancient-coin-like pattern and severe nuclear atypia. Malignant gastrointestinal stromal tumors which presented at least one of above-mentioned parameters can be divided into clinical stage 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 are of the highest degree of malignancy regardless of the number of parameters. It finds that the clinical stage and grade are associated with biologic behavior strongly.