Evaluation of Survival and Prognostic Factors in Patients with Gastrointestinal Stromal Tumor

Background: Gastrointestinal stromal tumors (GIST) comprise 1% of primary tumors of gastrointestinal (GI) tract. The aim of this study is to survey overall survival (OS), disease free survival (DFS) and also the effect of some factors such as mitotic count, tumor size, age, gender on prognosis and time of appearing recurrence which is rarely studied in Iran.  Methods: This study is a type of survival analysis, which was performed on 95 patients who were suffering from GIST during 2004-2017 within Yazd, Shiraz, Kermanshah and Kerman cities. Statistical data were analyzed by SPSS version 21 and the patients^, OS and DFS were calculated by Kaplan- meier test. Investigation of risk factors such as age, gender, mitotic count and tumor size on prognosis, time of recurrence (local recurrence or metastasis) were evaluated by log rank test and cox regression model. Result: OS and DFS were studied on these patients. In this survey OS was 96%, 94% and 83% in the first year, second year and the fifth year, and DFS was 87%, 81% and 51% respectively. In addition, some factors like mitotic count and tumor size and risk classification were significantly related to disease free survival based on log rank test, and mitotic count and male gender were negative predictor of malignant behavior based on cox regression model (p<0.05). Conclusion: The survival time in these patients after introduction imatinib remarkably increased and some factors such as mitotic count has prominent effect on prognosis, in comparison with other factors.