Signet-ring cell carcinoma of the colon and rectum - A matched control study

PURPOSE: There is little information comparing signer-ring cell carcinoma t o common non-signet-ring cell colon and rectal cancers. The aim of this stu dy was to better define the clinicopathologic differences between these two distinct entities. METHODS: Using a prospective database of 5,350 surgical patients with rectal cancers operated on at Memorial Sloan-Kettering Cance r Center between 1986 and 1997, 46 patients with signer-ring cell carcinoma were identified. Signet-ring cell carcinoma lesions were those in which si gnet-ring cells constituted more then 50 percent of the tumor. Six patients who presented with recurrent disease were excluded from the study. Control patients were matched for age, gender, TNM stage, primary site, procedure, ;md adjuvant therapy. Age, primary site of the tumor, stage at presentation , and survival times of patients with signer-ring cell carcinoma were also compared with 3,371 patients with primary non-signet-ring cell rectal cance rs. Survival was calculated using Kaplan-Meier survival estimates. RESULTS: Mean age of the signet-ring cell carcinoma group was 59 +/- 12 years and m edian age was 61 (range, 20-91) years. Male-to-female ratio was 1.1:1. Lymp hatic and peritoneal spread was more common among the signer-ring cell carc inoma group. Approximately one-third of signet-ring cell carcinoma patients presented with metastatic disease. Mean survival time of the signer-ring c ell carcinoma group was 45.4 months (95 percent confidence interval, 26.9-6 3.8) compared with 78.5 months (95 percent confidence interval, 62.0-94.9) for the control patients group; P = 0.02 by the log-rank test. The cumulati ve survival curve of patients with signet-ring cell carcinoma resembles tha t of patients with poorly differentiated rectal cancers. CONCLUSIONS: Patie nts with signer-ring cell carcinoma of the colon and rectum have a worse pr ognosis compared with matched controls with the same stage of disease.