Progressive microsatellite changes in replication error positive (RER+) endometrium were used to reconstruct evolutionary stages of nonfamilial adenocarcinoma. RER+ putative endometrial precancers (atypical endometrial hyperplasias) progress to RER+ carcinomas, which retain some of the altered microsatellites acquired in earlier precursor stages. The RER+ phenotype may provide a specific marker for early-stage endometrial neoplasms that cannot be resolved by routine histopathology and may be a useful tool to stratify stages in the evolution of RER+ tumors.
This work was supported by grants EDT-86 (to G. L. M.) and 94–671 (to A. S. J.) from the American Cancer Society and by NIH Training Grant T32-HL07627 (to W. C. F.).