Abstract
We investigated the significance of intraoperative peritoneal lavage cytology (CY) in 868 patients with colorectal cancer. According to the classification by the depth of invasion, carcinomas of m, sm and mp had negative CY, and carcinomas of se, a2, si and ai had positive CY more frequently than those of ss and a1. The rate of positive CY increased as peritoneal dissemination and lymph node metastasis became severer. With reference to histological type, CY was predominantly positive in poorly-differentiated carcinomas. The cumulative 5-year survival rate was significantly poorer in patients with positive CY than those with negative CY. Based on multivariate analysis, CY proved to be a significant covariate associated with survival. When the survival rate was compared with the results of CY and the presence or absence of peritoneal dissemination (P), the survival rate was significantly higher in patients with negative CY irrespective of the presence of P. In patients with cur A and B, peritoneal recurrence was less in patients with a negative CY irrespective of the presence of P. The above results suggest that patients with highly advanced carcinomas predominantly have positive CY and that CY is one of important prognostic factor.
