A study on significant prognostic factors in patients with stage IB Gastric Cancer

Author(s): Keishiro Aoyagi, Yu Tanaka, Hideaki Kaku, Yuya Tanaka, Taro Isobe, Naotaka Murakami, Seiya Ishibashi, Fumihiko Fujita

Objectives:

Aim: Most stage IB gastric cancers can undergo curative resection by surgery, but early stage and advanced cancers are mixed at this stage and little is known regarding their prognostic factors. In this study, factors involved in relapse-free and overall survival in stage IB gastric cancer were examined.

Methods: One hundred eighty-six patients with stage IB gastric cancer who underwent resection at our hospital between 1994 and 2018 were analyzed. Univariate analyses of factors involved in relapse-free survival and overall survival were performed using bivariate analyses, and multivariate analyses were undertaken using the Cox proportional hazards model.

Results: Five-year survival rate was 83.7% in stage IB (84.3% in T2N0 and 82.3% in T1N1). For relapse-free survival, a significant difference was observed in the degree of lymphatic vessel invasion and the number of lymph node metastases in the univariate analysis, and in the multivariate analysis, the degree of lymphatic vessel invasion was an independent prognostic factor. For overall survival, there were significant differences in age, clinical lymph node metastasis, tumor location, number of dissected lymph nodes, and preoperative co-existing disease in the univariate analysis. Age and clinical lymph node metastasis were independent prognosis factors in the multivariate analysis.

Conclusion: For relapse-free survival, the degree of lymphatic vessel invasion was an independent prognostic factor, and for overall survival, age and clinical lymph node metastasis were independent prognostic factors. We suggest that adjuvant chemotherapy should also be considered in cases with severe lymphatic invasion.