Abstract
This study was conducted to assess the usefulness of peritoneal lavage cytology as a prognostic factor in colorectal cancer patients. The subjects were 687 colorectal cancer patients who underwent resections for colorectal cancer and peritoneal lavage cytology from January 2005 to April 2014. Cases were considered ‘positive’ when diagnosed as class III-V. The association between positive peritoneal lavage cytology and clinicopathological features or prognostic factors was investigated. Multivariate analysis showed that depth of invasion (T4), lymphatic invasion (ly2-3), and peritoneal dissemination were independent risk factors for positive peritoneal cytology. In the patients who underwent curative resection, overall survival and disease-free survival two years after operation were significantly shorter in the positive cytology group. Positive peritoneal lavage cytology is a risk factor and a significant prognostic factor in colorectal cancer.
