Increased carcinoembryonic antigen expression in cervical intraepithelial neoplasia grade 3 and in cervical squamous cell carcinoma

Carcinoembryonic antigen (CEA) is a highly glycosylated cell surface protein that is overexpressed in a variety of human tumors and has been used as a tumor marker for disease progression in colorectal cancer patients. Recently, CEA has been used as a target for vaccine therapy against advanced CEA-expressing colonic adenocarcinomas. Previous reports have found elevated serum CEA levels in patients with cervical cancer, although this did not correlate with disease progression. In this study, cervical biopsy specimens from patients with normal histology, cervical intraepithelial neoplasia (CIN) grades 1 to 3, cervical squamous cell carcinoma (SCC), and adenocarcinoma were evaluated for CEA expression by immunohistochemistry by using the monoclonal antibody COL-1. Staining intensity was graded on a scale of 0 to 3 and was correlated with histologic diagnoses. CEA staining intensity was significantly increased in high-grade squamous lesions (CIN III and SCC) compared with normal cervical mucosa and CIN grades I or II (P <.0001). There was a linear correlation between grade of lesion and staining intensity (r = 0.71). CEA expression increased most significantly between CIN grades 2 to 3. Only 1 of 7 primary cervical adenocarcinomas expressed CEA. Only 1 of 10 patients with high CEA expression in their tumors by immunohistochemistry had elevated serum CEA. We thus have shown that lesional CEA expression increases in CIN 3 and SCC without elevations in serum CEA. CEA expression may be a useful diagnostic tool and a useful marker for identifying those at risk for progressive cervical neoplasia. HUM PATHOL 31:1357-1362.