PRIMARY SIGNET-RING CELL-CARCINOMA OF COLORECTUM - AN AGE-MATCHED ANDSEX-MATCHED CONTROLLED-STUDY

Objective: To evaluate the differences of clinicopathological features between colorectal signet ring cell carcinoma and ordinary adenocarci noma. Methods: The clinicopathological data of 28 cases with primary c olorectal signet ring cell carcinoma was reviewed and compared with th e data from 56 age- and sex-matched patients with ordinary adenocarcin oma. Results: Fifteen cases (53.5%) with primary signet ring cell carc inoma were younger than 40 yr of age. Compared with 985 ordinary adeno carcinoma cases, signet ring cell carcinoma is present in excess in yo unger patients (p < 0.005). Further comparison with 56 age- and sex-ma tched ordinary adenocarcinomas showed that signet ring cell carcinomas could affect any sites of colon, presented as scirrhous appearance mo re frequently, had a higher percentage of stage III or IV tumors (78.6 vs 48.2%, 14.3 vs 7.2%, p < 0.005), had a higher rate of peritoneal s eeding (35.7 vs 12.5%, p < 0.005) but a lower rate of liver metastasis (14.3 vs 32.1%, p < 0.005), and had a lower curative resection rate ( 64.2 vs 80.4%, p < 0.005) and a higher local or distant metastasis rat e (61.1 vs 17.8%, p < 0.05). Survival with signet ring cell carcinoma is lower than that of ordinary adenocarcinoma, ''Stage-on-diagnosis'' and ''presence of subsequent distant metastasis'' were the major facto rs influencing survival of signet ring cell carcinoma patients. Conclu sion: The delay in diagnosis reduces the chance of curative resection, increases the possibility of local or distant metastasis postoperativ ely, and, thus, shortens the survival chances. To improve outcome, rec ognition of the factors responsible for this delay should be stressed so that this tumor may be found at a stage when cure is possible.