Impact of therapy and androgen receptor polymorphism on sperm concentration in men treated for testicular germ cell cancer: a longitudinal study

BACKGROUND: Testicular cancer (TC) patients have a high survival rate, and the question of post-therapy recovery of sperm production and its dependence on genetic predisposition is of major interest. METHODS: Ejaculates were obtained from 112 TC patients at one or more of the following time points: post-orchidectomy, or 6, 12, 24, 36 and 60 months post-therapy. The lengths of the androgen receptor (AR) function modulating CAG and GGN repeats in leukocyte DNA were also analysed. RESULTS: No significant decrease in sperm concentration was seen in men who received 1-2 cycles of adjuvant chemotherapy (ACT). Radiotherapy (RT) or more than two cycles of chemotherapy (HCT) caused an initial decline in sperm concentration, which returned to pre-treatment levels 2-5 years after therapy. In the HCT group, sperm concentration 12-24 months post-treatment (T(12-24)) was inversely correlated with CAG length (rho = -0.72, P = 0.03). The type of treatment, but not the concentration at T(0), was an independent predictor of sperm concentration at T(6) (P < 0.0005) and T(12-24) (P = 0.004). CONCLUSION: ACT did not induce a significant decline in sperm concentration. After HCT and RT, a significant reduction of sperm concentration was observed, recovering to pre-treatment levels 2-5 years post-treatment. In HCT-treated patients, the AR CAG length influenced the recovery of spermatogenesis.