Are serum inhibin concentrations new markers of placental tumours in the course of chemotherapy?

BACKGROUND

The study was conducted to evaluate whether the detection of serum molecular forms of inhibin (A and B) could be useful for the diagnosis, prognosis and follow-up of placental tumours.

METHODS

A total of 17 patients with hydatidiform mole (n = 13), invasive mole (n = 1) or choriocarcinoma (n = 3) were studied; serum concentrations of inhibins A and B, human chorionic gonadotrophin (HCG) and its free beta subunit (HCGbeta) were measured before chemotherapy (after mole evacuation for eight patients) and also during the course of chemotherapy (for 10 patients).

RESULTS

After evacuation or before chemotherapy for refractory disease, serum inhibin A and B concentrations were found to be increased in 10/17 and 4/17 patients, when HCG and HCGbeta were high in all patients. In 10 patients with a follow-up during treatment, nine had a high concentration of inhibin A which correlated with those of HCG and HCGbeta. Normalization of inhibin A was faster than that of HCG and HCGbeta for three and six patients respectively. There was no correlation between changes of inhibin B and HCGbeta concentrations.

CONCLUSIONS

Our results suggest that inhibins A and B are not useful markers and that HCG determination still remains the most useful marker for diagnosis and follow-up of placental tumours.