Serum levels of squamous cell carcinoma antigen SCC, carcinoembryonic antigen CA 125, and tissue polypeptide antigen were determined in 142 patients with primary cervical carcinoma, 60 patients with precancerous lesions and in 129 healthy women. With regard to elevated tumour marker levels, specificity ranged from 94.6% to 97.7%. Sensitivity was highest (44.4%) for SCC. A stage relation was found for all tumour markers except for carcinoembryonic antigen. In stage Ib, SCC levels increased according to tumour volume. SCC, CA 125 or both markers were elevated in 7 of 8 patients with pelvic lymph node metastases compared with only 17 of 58 patients with negative nodes (P = 0.005). In a multivariate analysis, pretreatment serum levels of SCC and CA 125 were found to be significantly related to patient survival, in addition to stage. In cervical SCC, the risk of a fatal outcome increased 16 times with SCC levels > or = 4.5 ng/ml, compared with SCC levels < or = 1.3 ng/ml. We conclude that pretreatment serum levels of SCC may be of value as an adjunct to clinical staging. In addition, serum determinations of SCC and CA 125 seem to be useful in predicting the risk of pelvic lymph node metastases and as prognostic risk factors for disease outcome.