Serum squamous cell carcinoma antigen in gynecologic malignancies with special reference to cervical cancer.

Squamous cell carcinoma (SCC) antigen was measured by double-antibody radioimmunoassay in the sera of 113 patients with gynecologic malignancies and 30 controls. The mean serum SCC antigen level was 9.24 ng/ml in those with cervical squamous cell carcinoma, 2.15 ng/ml in those with other gynecologic malignancies, and 1.25 ng/ml in controls. With a cutoff value of 2.23 ng/ml (2 SD above the mean of the control group), the rate of SCC antigen elevation was 54% in cervical cancer (78), 14% in vulvar or vaginal cancer (7), 22% in ovarian cancer (18), and 10% in endometrial cancer (10). In cervical squamous cell carcinoma, the rates of elevated SCC antigen level increased with disease advancement in stages 0, I, II, III, and IV, by 13, 50, 53, 78, and 100%, respectively. In early-stage cervical squamous cell carcinoma, SCC antigen was not sensitive enough for screening. However, if elevated, serum SCC antigen levels decreased rapidly after successful surgical treatment. One case with a serum SCC antigen level above 65 multiples of the cutoff value had widespread cancer and postoperative recurrence. In the advanced case, the sensitivity was much higher. In the recurrent case, the positive rate was 73%. Serum SCC antigen level is useful in predicting the prognosis and monitoring the course of cervical squamous cell carcinoma, especially in the detection of a recurrence.