The prognostic value of the pretreatment serum CA 125, squamous cell carcinoma antigen (SCC), and carcinoembryonic antigen (CEA) levels in relation to tumor type, vascular invasion by tumor cells, and lymph node metastases was investigated in 77 patients with cervical adenocarcinoma. In Stage IB (International Federation of Gynecology and Obstetrics [FIGO]), the five-year actuarial survival of patients with pretreatment serum CA 125 levels greater than 16 U/ml was 52.4% versus 95.6% when normal serum CA 125 levels were determined (P less than 0.01). Pretreatment serum SCC or CEA levels had no substantial prognostic value. In Stage IB (FIGO), 42% of the patients with elevated serum CA 125 levels had lymph node metastases versus 4% when normal levels were found (P = 0.012). The presence of vascular invasion (P = 0.01) or lymph node metastases (P = 0.001) was associated with an increased risk for recurrent disease. Adenosquamous tumors showed a higher incidence of vascular invasion (P = 0.05) and a higher incidence of elevated serum CA 125 levels (P = 0.03). Particularly in Stage II, adenosquamous tumors were found to have a poorer prognosis than adenocarcinomas (P = 0.0566). We conclude that in cervical adenocarcinoma serum CA 125 is an important prognostic factor and an implicit indicator of tumor virulence.