Serum human epididymis protein 4 vs. carbohydrate antigen 125 in ovarian cancer follow-up

Background: The addition of human epididymis protein 4 (HE4) to carbohydrate antigen 125 (CA125) in ovarian cancer (OC) assessment has been proposed. We compared the clinical value of biomarker changes in a prospective series of patients undergoing OC monitoring. Methods: We studied 43 patients (79% post-menopausal), followed for 3.5 ± 3.1 years. Serous OC was prevalent (53.5%), with 81.4% of patients diagnosed at late stages. Both cut-offs and reference change values (RCV) were used for assessing significant marker changes. Results: The use of cut-offs for CA125 and HE4 interpretation appeared equally fitting the evaluation of disease progression defined according to running guidelines, performing better than RCV criterion. However, both markers were simultaneously over cut-offs only in 46% of samples and changed in agreement in 35% of cases. The inspection of individual longitudinal trends indicated as main causes of disagreement the influence of renal impairment on HE4 concentrations and the more significant rate of decrease of CA125 vs. HE4 concentrations early after treatment. CA125 and HE4 changes according to RCV were not predictive of OC progression. Conclusions: CA125 appears the most reliable biomarker for OC monitoring, whereas HE4 contributes additional information only in a minority of cases.