Analysis of risk factors of stage IV gastric cancer from the SEER database.

INTRODUCTION Gastric cancer is the fourth most common cancer in the world. By the time the patients are diagnosed with stage IV gastric cancer, many patients already have distant metastases. There is no unified systemic treatment plan in existence. The use of gastrectomy is ambiguous in patients with stage IV gastric cancer. The objective of this study was to evaluate the beneficial outcome of gastrectomy in patients with stage IV gastric cancer. METHODS Clinical information of patients with gastric cancer from 2000 to 2010 in the Surveillance, Epidemiology, and End Results database were extracted and analysed. The risk factors for stage IV gastric cancer were also analysed. RESULTS We observed that the median survival time for patients after surgery was greater than that for patients not treated surgically. The five-year survival rate for chemotherapy patients was higher than that of non-chemotherapeutic patients. Patients who receive both chemotherapy and surgery could achieve a more significant survival benefit. The risks following gastrectomy (partial, subtotal, hemi-) were lower than those of other surgical procedures, which provided guidance on the choice of surgical method. The numbers of regional lymph node metastasis were found to be related to prognosis. CONCLUSIONS In patients with stage IV gastric cancer, gastrectomy (partial, subtotal or hemi) should be selected when surgery is necessary. The number of regional lymph node metastasis could be considered as a prognostic factor for patients with stage IV gastric cancer and lymph node dissection could reduce the risk of patients undergoing surgery.