Abstract
The clinicopathological features of 21 cases of poorly differentiated adenocarcinoma of the colon and rectum resected in our department from 1988 to 1996 were compared with those of 472cases of well and 162cases of moderately differentiated adenocarcinoma. Poorly differentiated adenocarcinomas were more frequently found in the right side of the colon. Eighty five point seven percent of poorly differentiated adenocarcinomas invaded beyond serosal and adventitical layer, and 28.6% of them had high grade lymph node metastasis. Sixty six point seven percent of poorly differentiated adenocarcinomas were Dukes C and D, and 57.1% were over 3b. Poorly differentiated adenocarcinomas were more advanced than well differentiated adenocarcinomas with significant difference. No differences were observed between poorly differentiated adenocarcinomas and well and moderately differentiated adenocarcinomas in frequency of liver and lung metastasis. However, the incidence of peritoneal dissemination was higher in poorly differentiated adenocarcinomas than in well and moderately differentiated adenocarcinomas at the time of primary surgery and recurrence. The curative A resection was done in 71.4% of poorly differentiated cases, and the five-year survival rate was 77.8% in cases with curative A resection. There was no significant difference in the five-year survival rate between poorly differentiated and well and moderately differentiated adenocarcinomas in case of curative A resection. Advanced disease was more often discovered in patients with poorly differeniated adenocarcinoma, however, the prognosis may be improved by early detection and sufficient lymphadenectomy.
