Tissue carcinoembryonic antigen levels in benign and malignant diseases of the breast.

The peroxidase-antiperoxidase histochemical method of staining for tissue carcinoembryonic antigen (CEA) was performed on 20 samples of malignant breast tissue, 20 samples of fibroadenomatous breast tissue, and 15 samples of breast tissue that variably contained minimal fibrosis (N = 7), ductal ectasia (N = 5), and sclerosing adenosis (N = 3; the fibrocystic changes of the breast). The intensity of staining was described to be either negative, weak, intermediate, or strong and was assigned a point value of 1, 2, 3, or 4, respectively. The following weighted average values of tissue CEA were obtained: carcinoma, 3.35 +/- 0.88; fibroadenomas, 2.85 +/- 0.67; fibrocystic changes, 2.13 +/- 0.52. Carcinomatous tissue is likely (55%) to display intense tissue staining, whereas fibrocystic disease (0%) or fibroadenoma (15%) are unlikely to exhibit such a reaction. The tissue CEA content between carcinoma and fibrocystic changes (P less than 0.01), carcinoma and fibroadenoma (P less than 0.01), and fibroadenoma and fibrocystic changes (P less than 0.05) are statistically significant.