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.