A Prospective Study of Inhibin in Granulosa Cell Tumors of the Ovary

Abstract

Elevated preoperative serum inhibin concentrations have been reported in patients with granulosa cell tumor of the ovary. The aim of this study was to determine if elevations in serum inhibin predated clinical recurrence in patients with a diagnosis of granulosa cell tumor. Twenty-seven consecutive patients with granulusa cell tumor were followed prospectively to assess the relationship between serum inhibin concentrations and disease status. The serum inhibin concentrations in normal postmenopausal women were <77-130 U/liter. In patients with granulosa cell tumor at initial surgery, mean inhibin concentrations preoperatively were 2831 U/liter in 4 postmenopausal subjects (range 2130-3323 U/liter) and 3680 U/liter in each of 2 premenopausal women. In 5 postmenopausal subjects with a histological diagnosis of granulosa cell tumor who underwent secondary surgery because of a recurrent palpable mass, mean inhibin concentrations were 4216 U/liter (range 2672-7360). In 3 patients with known or suspected residual disease despite a secondary debulking operation the serum inhibin concentrations were 475, 1000, and 2541 U/liter. In 13 subjects who were clinically disease free with a previous diagnosis of granulosa cell tumor, serum inhibin concentrations remained within the normal range for reproductive status. We conclude: (1) Preoperative serum inhibin concentrations are typically elevated sevenfold above the normal premenopausal follicular phase levels in women with granulosa cell tumor; (2) after surgery, serum inhibin levels may become elevated up to 2 years before further surgery is undertaken; and (3) serum inhibin concentrations appear to be a valuable tumor marker for the diagnosis of primary or recurrent granulosa cell tumor.