[Postoperative prognostic factors for carcinoma of the thoracic esophagus]

To evaluate significant postoperative prognostic factors for esophageal carcinoma, clinicopathological findings and several markers for biological malignant potential were studied, including cell nuclear DNA contents, EGF receptor, p53 protein, MMP-2, Ki-67 positive cell rate, and tumors infiltrating Leu 7 cells. The subjects of this study were 96 patients with thoracic esophageal carcinoma, who underwent radical surgery with extended lymphadenectomy. In the pathological findings, the postoperative survival rate significantly correlated with depth of invasion (pT1(-2) vs. pT3, p = 0.003), lymph node involvement (pNo vs. pN1, p = 0.0002), vascular invasion (-vs. +, p = 0.0003), stage (pSt. 1-2A vs. 3, p = 0.0018), and the number of node involvements (1-3 vs. more than 4, p = 0.025). Analyzing the markers for the malignancy, a significant difference in postoperative mortality due to the relapse was recognized with p value of 0.0009 between Ki-67 positive (under 1%) and Ki-67 negative (over 1%) tumor. Ki-67 positive tumor significantly correlated with the mortality in both cases with pNo (p = 0.024) and pN1 (p = 0.020). Low-grade tumor infiltrating Leu 7 cells significantly correlated with the mortality (Grade 1+ vs. 2+, p = 0.013; Grade 1+ vs. 3+, p = 0.008). These results suggest that Ki-67 study is a useful prognostic factor after radical surgery for thoracic esophageal carcinoma.