Prognostic impact of immunohistochemical expression of Ki-67 in patients with advanced gastric cancer who underwent curative resection.

Abstract

19 Background: Ki-67, tumor proliferation marker, is an important prognostic factor in a variety of cancers. In the present study, we investigated the prognostic value of immunoexpression of Ki-67 in patient with gastric cancer who underwent curative resection. Methods: We retrospectively analyzed 241 patients who had undergone curative gastrectomy at Gachon University Gil Hospital between January 2008 and July 2009. Ki-67 proliferation index (PI) by immunohistochemistry on formalin-fixed, paraffin-embedded material and the other clinicopathologic variables were evaluated by univariate and mulvariate analysis. Results: The median follow-up from surgery was 12 months (range, 0.5-26.7 months) and mean recurrence-free survival was 23 months (95% confidence interval, 21.8-24.1 months). The mean Ki-67 PI was 40% (range, 5-90%). No significant correlation was found between Ki-67 PI and other clinicopathologic variables including histologic grade and pathologic TNM (pTNM) stage. Univariate analysis revealed that significant prognostic factors of recurrence-free survival included age, preoperative serum albumin, pre-operative hemoglobin, surgery type, pTNM, histologic grade, lymphatic vessel invasion, peri-neural invasion, and Ki-67 PI. In the multivariate analysis besides pTNM (p=0.046), lymphatic vessel invasion (p=0.024), and surgery type (p=0.047), Ki-67 PI (p=0.005) also remained as an independent prognostic factor of recurrence, whereas the other factors lost its prognostic value. Conclusions: Our results suggest that high Ki-67 PI is independent, poor prognostic factor of recurrence in patient with gastric cancer who underwent curative resection. No significant financial relationships to disclose.