Prognostic factors in stage IV gastric cancer: univariate and multivariate analyses

BACKGROUND: The prognosis of stage IV gastric cancer is poor with the 5-year survival rate still being about 10%.METHODS: We classified 130 patients with stage IV gastric cancer into four groups: peritoneal metastasis, liver metastasis, lymph node metastasis, and multiple factor groups, according to the factors that determined stage IV in each patient and compared survival in the four groups. We also performed univariate and multivariate analyses of various prognostic clinicopathological factors. The 5-year survival rate in the patients with stage IV gastric cancer was 7.4%.RESULTS: No significant differences were observed in survival among the four groups. Univariate analysis showed significant differences in survival among the categories of lymphatic invasion ( P = 0.0045), venous invasion ( P = 0.0024), peritoneal metastasis ( P = 0.0019), postoperative chemotherapy ( P = 0.0385), curability ( P = 0.0001), and lymph node dissection ( P = 0.0001). In the curability B group, survival was prolonged in the postoperative chemotherapy group. Multivariate analysis revealed the highest relative hazard (RH) for lymph node dissection (RH, 2.261), followed, in descending order, by curability (RH, 1.905), peritoneal metastasis (RH, 1.896), lymphatic invasion (RH, 1.736), and venous invasion (RH, 1.481).CONCLUSION: As prognostic factors in stage IV gastric cancer, the tumor factors of peritoneal metastasis and vessel invasion, and the treatment factors of curability and lymph node dissection may be important, and active treatment appears to improve survival.