Ovarian vein vs peripheral blood CA125 serum levels: a comparative study

Direct sampling from the ovarian vessels may be considered as a supplementary method of ovarian cancer diagnosis providing further clinical information for the staging and localization of ovarian carcinoma. This present multi-institutional study evaluates and compares the clinical values of CA125 serum levels sampled directly from the right and left ovarian veins to the peripheral blood supply in an effort to correlate CA125 values to tumor volume and location.

Serum samples from 43 patients with primary ovarian carcinoma were evaluated for the presence of CA125. All patients underwent surgery for the primary tumor, and stage was defined according to the classification of the International Federation of Gynecology and Obstetrics. The measurement of CA125 was accomplished by radioimmunoassay.

Twenty of 20 patients with serous papillary adenocarcinoma, 8/12 patients with tumors of low malignant potential, 6/6 patients with endometrioid carcinoma, 2/4 patients with clear cell adenocarcinoma, and 1/1 patients with mucinous adenocarcinoma had elevated (>35 U/mL) peripheral CA125 levels. Peripheral blood CA125 values had Spearman correlation coefficients of 0.96 and 0.95 with left and right ovarian vein CA125 values, respectively. Similarly, left and right ovarian vein CA125 values had a correlation coefficient of 0.98. CA125 values were moderately correlated with tumor volume in this sample. Spearman correlation coefficients between left ovarian vein CA125 values and left and right tumor volume were 0.51 and 0.43, respectively. Spearman correlation coefficients between right ovarian vein CA125 levels and left and right tumor volume were 0.41 and 0.46, respectively. Those between peripheral CA125 values and left and right tumor volume were 0.56 and 0.36, respectively. Median CA125 values for stage I diseases were elevated (53.25, 101.5, and 74.50 for left, right, and peripheral, respectively).

Direct sampling from the ovarian veins compared to that from the peripheral veins did not appear to offer additional information regarding ovarian tumor volume and location.