Inhibin B

Notes

Inhibin is a glycoprotein secreted by granulosa cells of the ovary and sertoli cells of the testis. It exists as a dimer of two subunits (alpha and beta) linked by disulphide bonds. They selectively suppress the secretion of pituitary follicle stimulating hormone and also have local paracrine actions in the gonads.

Inhibin B is rarely requested and is only available for the monitoring of patients after surgery for recurrence of ovarian granulosa tumours. Tumour markers are not diagnostic and are of most use in monitoring response to treatment and early detection of relapse. Normal values do NOT exclude malignancy.

In pre-menopausal fertile woman, inhibin B levels vary throughout the menstrual cycle. Due to the paucity of studies and the variability of inhibin B levels between women throughout the cycle, reference intervals serve only as a guide. Hormone replacement therapy will artificially stimulate inhibin B production in the menopause.

Sample requirements

For adults, blood taken into a 5mL narrow gold top gel tube.

Storage/transport

Send immediately to the laboratory at ambient temperature. Samples cannot be stored overnight and serum must be frozen as soon as possible after centrifugation.

Required information

Relevant clinical details including reason for the request.

Turnaround times

Samples are sent to a referral laboratory for analysis with results expected back within 3 weeks.

Reference ranges

Age and sex dependant reference ranges are supplied with the reports from the assaying laboratory.

Further information

• http://labtestsonline.org.uk/understanding/analytes/tumor-markers/
• http://emedicine.medscape.com/article/254489-workup
• http://patient.info/doctor/ovarian-cancer-pro

Page last updated: 07/02/2019