Male gonadal function after chemotherapy in survivors of childhood malignancy

Investigations of adult patients have shown that chemotherapy causes gonadal damage, but much less information is available about the impact of chemotherapy on gonadal function in children with malignant disease. At one time, being prepubertal during therapy was thought to confer some protection against chemotherapy induced gonadal damage. However, recent studies have indicated otherwise. We designed this study to assess gonadal function in 15 postpubertal males who had received polychemotherapy for a malignant disease during childhood and we compared them with 13 control adults males. The mean age of the patients at the time of the study was 18.2 +/- 3.6 years (range 13.8-29.0), and when given chemotherapy treatment was 10.2 +/- 3.0 years (range 6-16). At that time 12 were prepubertal and at the time of the study all were Tanner V. The mean interval from the completion of treatment until the study was 6.42 years (range 2.0-16.5). All patients had received polychemotherapy. We evaluated testicular size, sperm counts, LH and FSH after GnRH test, and testosterone levels. Puberty had progressed normally in all patients. We found no significant differences in testosterone and basal LH levels between patients and controls. However, we detected an appreciable difference in peak LH levels (P < 0.05) and in basal and peak FSH levels (P < 0.001). Seven patients had exaggerated LH response to GnRH, indicating dysfunction of the Leydig cells. The results of semen analyses were: 8 patients had azoospermia, 3 oligospermia, and 1 patient had a normal semen analysis. All patients with semen abnormalities presented a basal and peak FSH higher than the mean +2 SD of the control group. In summary, we found no evidence of gonadal protection in prepubertal patients. We found a high incidence of germinal cell damage, whereas Leydig cell abnormalities were found less often. An endocrine study of patients that have received chemotherapy is warranted.