Tumor marker studies of cervical smears. Potential for automation.

The distribution of three tumor markers, epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA) and prekeratin (PK) was studied in exfoliated epithelial cells in cervical smears using an immunoalkaline phosphatase staining technique to demonstrate the antigens. EMA was expressed by abnormal cells in a consistent and reproducible fashion whereas the other two markers were variably expressed by both normal and abnormal cells. Our results suggest that immunocytochemical staining for EMA could be of value not only for the diagnosis of cervical intraepithelial neoplasia but also for the automated screening of cervical smears.