Increased risk of testis failure in testicular germ cell tumor survivors undergoing radiotherapy

Testicular germ cell tumors (TGCTs) are prevalent in males of reproductive age. Among the available therapeutic choices, pelvic radiotherapy (RT) and simple surveillance (SURV) are usually pursued. However, RT is considered to have life-threatening effects on testicular functions. In this study we sought to clarify this issue by evaluating sperm parameters and sex hormones in 131 TGCTs RT-treated-patients at both baseline (T0) and 12 (T1) and 24 months (T2) of follow-up. An age-matched group of 61 SURV patients served as control. Sperm parameters were comparable between SURV and RT at T0. The RT group showed a significant reduction of all sperm parameters at T1 (all values < 0.05 T0 and SURV at T1) and increased levels of sperm aneuploidies, with some degree of recovery at T2. On the other hand, despite normal levels of total testosterone being detected in both groups, luteinizing hormone (LH) levels in the RT group progressively increased at T1 and T2 with a relative risk of developing subclinical hypogonadism of 3.03 (95% CI: 1,50-6,11) compared to SURV. Again, compared to SURV, exposure to RT was associated with a 5.78 fold (95% CI: 2,91-11,48) risk of developing vitamin D insufficiency. These data suggest a likely RT-dependent impairment of the Leydig cell compartment.