CA125-response assessment in epithelial ovarian cancer.

To assess the clinical potential of serial serum CA125 measurements in the follow-up of patients with epithelial ovarian cancer, 74 consecutive unselected patients with histologically confirmed ovarian carcinoma were studied prospectively. There was an 83% concordance between clinical assessment and CA125 assessment of response. The positive predictive values of a rising CA125 for disease progression and a falling CA125 for disease regression were 0.93 and 0.94, respectively. The absolute CA125 values during observations of complete response (mean 96 U/ml; 95% confidence interval; 33 to 128 U/ml), partial response (mean 134 U/ml; 95% confidence interval; 98 to 159 U/ml) and stable or progressive disease (mean 391 U/ml; 95% confidence interval; 282 to 545 U/ml) were significantly different. A randomized study is required to determine whether CA125 monitoring has any benefit in terms of outcome, and particularly survival, in epithelial ovarian cancer.