Abstract

Objectives:

In patients with a granulosa cell tumor of the ovary, the value of serum inhibin A and B concentrations for the assessment of disease status was investigated.

Methods:

In 30 consecutive patients with a stage I–III granulosa cell tumor, inhibin A and B concentrations were measured in pre- and post-treatment serum samples. Clinical data concerning diagnosis, treatment and follow-up of these patients were related to serum inhibin A and B concentrations. Serum samples from 41 premenopausal females with cervical dysplasia served as controls.

Results:

In 30 patients, 13 (43%) recurrences were observed during a median follow-up of 10 years (range 1–31 years). Serum inhibin A and B concentrations were elevated in respectively 67% and 89% of the patients at diagnosis, and in 58% and 85% at recurrence. Inhibin A and B concentrations were normal in all controls. Sensitivity of inhibin A testing for the diagnosis of granulosa cell tumor was 67% with a specificity of 100%, compared to 89% and 100% respectively for inhibin B (ns). Elevations in serum inhibin B concentrations predated recurrences by a median of 11 months. None of the patients in remission showed increased concentrations of inhibin A and B.

Conclusion:

Inhibin B seems to be the predominant form of inhibin secreted by granulosa cell tumors and appears to reflect disease status more accurately than inhibin A. Measurement of serum inhibin B concentrations may be preferred for the follow-up of granulosa cell tumors (Fig 3).

Figure 3: Serum inhibin A and B concentrations of patient A. At diagnosis patient A was a 49 year old premenopausal female, and therefore the serum inhibin A concentration was considered normal and the inhibin B concentration elevated. After surgery and adjuvant chemotherapy, she became postmenopausal and both inhibin A and B decreased to normal postmenopausal levels. Fifty months after diagnosis, serum inhibin A and B concentrations were both within the normal range. Tumor recurrence was confirmed 10 years after the initial diagnosis. In retrospect, serum inhibin B was already increased 19 months before the clinical manifestation of recurrent disease. After surgical debulking, inhibin B initially decreased, but shortly thereafter it increased again. The rapid elevation of inhibin B at that stage, compared to the more gradual increase before, reflected the swift deterioration of the patient’s clinical condition. She died 12 years after the initial diagnosis. (Reprinted from Mom CH, Engelen MJA, Willemse PHB, et al. Granulosa cell tumors of the ovary: the clinical value of serum inhibin A and B levels in a large single center cohort. Gynecol Oncol. 2007;105:365-372, with permission from Elsevier.)