Chromosome constitution of adenoma and adenocarcinoma of the colon

Abstract

The chromosome patterns of 17 adenomas and 7 adenocarcinomas of the colon were studied using a direct technique. The typical adenomas showed definite abnormalities of chromosome pattern. Many pseudodiploids and many cells with counts of 47 were identified. These latter appeared due to a trisomy. Nondisjunction with persistence of the resulting abnormal stemline is postulated. Those adenomas with areas of histologic atypia showed greater hyperploidy and more numerous individually abnormal chromosomes. Hyperploidy was also marked in three adenomas which were in whole or part villous. These two groups were similar to the markedly hyperploid and aneuploid carcinomas studied. Two poorly differentiated adenocarcinomas were much less hyperploid than the remaining five better differentiated adenocarcinomas.