Combination of serum hCG beta and p53 tissue expression defines distinct subgroups of serous ovarian carcinoma.

Serous ovarian carcinoma comprises a clinically heterogenous group of tumors, and molecular markers stratifying patients into clinically meaningful subgroups are needed. Numerous markers have been evaluated, but none of them has yet been routinely incorporated into clinical practice. Previously we have found that elevated serum levels of the free beta subunit of human chorionic gonadotropin (hCG beta) and aberrant p53 expression confer poor prognosis in ovarian carcinoma. The aim of our study was to evaluate their combined effect in predicting the outcome of patients with serous ovarian carcinoma. The study material consisted of 173 consecutive patients treated for primary serous ovarian carcinoma in 1 institution between 1990 and 2000. The preoperative serum level of hCG beta was analyzed by a ultrasensitive and specific immunofluorometric assay, and p53 tumor tissue expression by immunohistochemistry using a novel classification. Elevated serum hCG beta (>or=2.0 pmol/L) was detected in 57 (33%) of 173 patients, and aberrant p53 expression in 103 (62%) of 167 interpretable cancers. Elevated hCG beta and aberrant p53 expression were strongly associated with poor prognosis (p < 0.0001 for both). Their additive prognostic effect was marked. Five-year survival was 14% (0-29%) when both markers were aberrant, 44% (29-60%) when either one was aberrant and 82% (70-94%) when both were normal. Preoperative serum hCG beta and tumor tissue p53 expression are feasible markers that divide serous ovarian carcinomas into clinically relevant subgroups.