Estimating Postoperative Survival of Gastric Cancer Patients and Factors Affecting it in Iran: Based on a TNM-7 Staging System

Abstract

Recently, reports have shown that gastric cancer has high abundance in Iran and is at the second level in men, and fourth in total. This study aimed to determine the 5-year survival of gastric cancer patients and to investigate factors affecting the performance, based on TNM-7 staging system. In this study, we investigated 760 patients with gastric cancer since the beginning of 1993 to the end of 2006 in the Iran Cancer Institute who underwent surgery. Survival of these patients was determined after surgery, and the effects of demographic characteristics such as age (during operation), sex, and information on diseases such as cancer site, pathologic type, stage of disease progress (Stage), metastasis and sites of metastases were evaluated. The 5 -year survival probability of patients was 28 %, and median survival time was 25.69 months. Univariate tests showed that sex, cancer site, and pathologic type have no significant effects on patient’s survival. But the probability of 5-year survival significantly decreases with increasing age, and as it is expected, those with metastases were significantly less likely to have 5-year survival, and disease stage was significantly effective on patients’ life (P<0.001). Simultaneous evaluation of different variables’ effects on the probability of survival using the multiple Cox proportional hazards models showed that age and stage disease variables were effective on the survival of patients. The 5-year survival of patients with gastric cancer is low in Iran, although it is improved compared to the past. It seems that one of the main reasons for low survival rate of these patients is a late referral of patients for diagnosis and treatment. Most patients refer in the final stages of the disease, at this stage most patients are affected by lymph nodes metastases, liver and as the result, their treatment will be more difficult.