Serum CA125 assay in the early diagnosis of recurrent epithelial ovarian cancer

The present retrospective study included 59 patients who had been treated for epithelial ovarian cancer and who showed an elevation of serum CA125 above 35 U/ml without clinical evidence of disease. Eight patients underwent chemotherapy at the time of serum antigen elevation (group A). The other 51 patients (group B) were periodically checked, and received further chemotherapy only when recurrent disease was detected. Forty-four of the 59 patients relapsed. One patient of group B experienced two different recurrences with two distinct time intervals. The median follow-up of survivors from CA125 elevation was 10 months (range 2-92 months). Of the 8 patients of group A, 3 (37.5%) developed recurrent disease after 14, 17 and 22 months, respectively, from antigen elevation. Of the 51 patients of group B, 41 (80.4%) relapsed. The overall recurrence rate was 82.4% (42/51). The median lead time between CA125 increase and clinical detection of relapse was 3 months (range 2-27 months). The present data confirmed the reliability of serum CA125 assay as predictor of clinical relapse in epithelial ovarian cancer. The recurrence rate seemed to be lower for patients who received chemotherapy at the time of CA125 elevation (37.5% versus 82.4%, p=0.02). However, the small number of patients, the short follow-up, and the non-randomized design of the study do not allow to draw any conclusion on the appropriate timing for second-line chemotherapy.