In the 37 tumors with matching benign tissues adjacent to the tumors, most benign breast epithelial cells exhibited negative or weak staining for CARM1 (mean IHC score, nuclear 50.00, cytoplasm 37.57); staining for CARM1 was significantly stronger in matched adenocarcinoma cells (mean IHC score, nuclear 111.35, cytoplasm 87.57). This evidence concerns the gene CARM1 and adenocarcinoma.