Introduction:
Male gonads are susceptible to the deleterious effect of anticancer therapy (chemotherapy, radiation to the pelvis, central nervous system, or total body irradiation). Hormonal dysfunction after anticancer treatment was evaluated in young male cancer survivors.

Material and methods:
In 153 male adolescent cancer survivors divided into three risk groups (low-LR, moderate-MR, and high-HR) and 24 controls, gonadal and pituitary hormones were analysed. FSH, LH, and testosterone levels were assessed in all the studied patients using immunoenzymatic techniques, dimeric inhibin B – by ELISA method.

Results:
All cancer survivor groups had lower mean values of inhibin B (86.87 ±69.07 ng/l vs. 161.07 ±60.64 ng/l; p < 0.001), and higher FSH (10.23 ±13.35 mIU/l vs. 4.38 ±2.39 mIU/l; p < 0.001) and LH (5.0 ±3.43 IU/l vs. 3.58 ±2.17 IU/l; p = 0.016); testosterone levels were comparable to the controls. Abnormal values of inhibin B were found: in 15.2% of survivors in LR, 47.6% in MR, and 94.1% – in the HR group. Elevated FSH levels were seen in 20.4% of survivors in LR, 47.4% in MR, and 92.2% in the HR group. The inhibin B: FSH ratio was lowered in MR and HR risk groups. We did not observe any influence of the age at treatment and the time since treatment termination on the analysed hormonal values.

Conclusions:
Anticancer treatment increases the risk of gonadal damage, particularly in the HR group. Patients and parents ought to be informed about the risk of lowered reproductive function, and pretreatment semen cryopreservation should be recommended.