Lymphangiosis as a predictor of outcome in patients with primary diffusely infiltrative adenocarcinoma of the colon and rectum

Objective: To investigate the relationships between outcome and clinicopathological factors, DNA flow cytometrical characteristics, and postoperative adjuvant therapy in patients with primary diffusely infiltrative colorectal adenocarcinoma. Design: Inception cohort study. Setting: A medical center that offers a mixture of primary, secondary, and tertiary care services. Patients: Among 7035 patients undergoing resection of primary colorectal adenocarcinoma from 1980 to 1996, 37 patients with a pathological diagnosis of primary diffusely infiltrative tumor were selected. All patients had received regular follow-up until February 28, 1998, or until death. Main Outcome Measures: Cancer-specific survival compared by log-rank test and Cox regression model. Results: Univariate analyses revealed tumor stage (stages II-III vs stage IV, P=.01) and severity of lymphangiosis (absent/mild vs moderated/severe, P=.04) were significant in predicting outcome. A proliferative index of greater than 20% was insignificant (P=.08) in predicting outcome. In a Cox regression model TNM stage and lymphangiosis were independently correlated with a worse outcome. When compared with tumors having less severe lymphangiosis, the odds ratio of death due to cancer in cases of tumors with moderate to severe lymphangiosis was 2.4 (95% confidence interval, 1.0-5.6; P=.05). Conclusion: Lymphangiosis and TNM stage were independently predictive of outcome in patients with primary diffusely infiltrative colorectal cancer.