Low serum inhibin B concentrations in male survivors of childhood malignancy

Abstract The aim of this study was to assess the value of serum inhibin B in detecting male gonadal dysfunction in childhood cancer survivors. 27 male postpubertal (Tanner's pubertal stage G5 or P6) and 12 pubertal (≥G2) patients were drawn from the endocrine follow-up protocol of childhood cancer patients at the Paediatric Clinic of Turku University Hospital, Turku, Finland. The average time (mean±S.D.) between the diagnosis and this study was 11.7±4.5 years in the postpubertal and 7.0±3.9 years in the pubertal group. Serum samples for the determination of follicle-stimulating hormone (FSH), luteinising hormone (LH), oestradiol, testosterone, and inhibin A and B dimers were collected. The demographic factors, pubertal stage and testicular size of the patient were measured at the same routine outpatient visit. Serum inhibin concentrations were correlated to testicular volume and gonadotrophin concentrations. Strong correlations were observed between testicular size ( r =0.80, P r =−0.58, P =0.002) and inhibin B concentration in the postpubertal group. Inhibin A was not detectable (