Detection of Tumor Markers Including Carcinoembryonic Antigen, APC, and Cyclin D2 in Fine-Needle Aspiration Fluid of Breast

Context.—The traditional triple test for breast cancer diagnosis is physical examination, mammography, and aspiration cytology. However, the accuracy of mammography on young women with nonatrophied breasts is poor compared with that for women older than 50 years, and additional methods for diagnosis of breast cancer are needed. Objective.—To investigate whether carcinoembryonic antigen (CEA), CA 15-3, and CA 125 concentrations in breast aspiration fluid are useful as breast cancer biochemical markers and whether APC and cyclin D2 gene promoter hypermethylation could be regarded as a breast cancer molecular marker. Design.—CEA, CA 15-3, and CA 125 concentrations were measured, and methylation status of the APC gene promoter 1A and the promoter region of the cyclin D2 gene were analyzed using a methylation-specific polymerase chain reaction assay of ex vivo breast aspiration fluid obtained from 49 samples of excised breast tissue. Setting.—The specimens were collected during a 1-year period in the tertiary care teaching hospital in Seoul, Korea. Patients.—Forty-nine patients with breast masses were surgically treated. Thirty-four patients had breast cancer, and 15 had benign breast disease. Results.—Aspiration fluid CEA concentrations were significantly higher in breast cancer cases than in cases of benign breast disease (mean, 69.90 ng/mg protein vs 0.68 ng/mg protein, respectively; P < .001). At 90% specificity of the assay (CEA, 2.13 ng/mg protein), the corresponding sensitivity for breast cancer detection was 62%, according to the receiver operating characteristic curve drawn. The APC gene promoter 1A and the promoter region of the cyclin D2 gene were methylated in 42% (14/33) and 70% (23/33) of the breast cancer aspiration fluid samples, respectively. A cumulative incidence of methylation of these 2 genes was 85% (28/33). The APC and cyclin D2 gene promoters were both unmethylated in the aspiration fluids from 19 women with nonmalignant breast disease. Conclusions.—Breast aspiration fluid CEA concentration and the methylation of the APC gene promoter 1A and the promoter region of the cyclin D2 gene can be used as tumor markers to overcome some of the limitations of aspiration cytology. In combination with the mammogram and physical examination, assays for these markers could be used to help determine a definitive diagnosis when cytologic results are suspicious for malignancy.