Serum ribonuclease activity in patients with ovarian tumors.

The RNase activities have been assayed in 1678 serum samples from a total of 209 patients. 52 with histologically confirmed ovarian carcinoma, 13 with benign tumors of the ovary, and 144 patients without any clinically detectable malignancy. The serum RNase activity is unequivocally increased in the group with ovarian cancer (p less than 0.01). Considering the distribution of the RNase activities with a margin at 300 ngeqvs/ml serum we find 8.3% false negative and 4.9% false positive results. The serum RNase activity does not display any evident relationship with tumor spread, histology, clinical grading (TNM), nor metastasis at the time of the blood taking. It is concluded that the serum RNase activity is a meaningful criterion together with the careful clinical examination for the diagnosis and the surveillance of ovarian cancer.