Incidence rates of testicular cancer are increasing among postpubescent men. This suggests that putative exposures may operate early in life and have changed over time. The age at which endocrine activity accelerates (age at puberty) may be such an exposure. This study was undertaken to investigate the relationship between age at puberty and testicular cancer risk.
A population-based case-control study was conducted in the province of Ontario, Canada which included males, aged 16 to 59 years, diagnosed with testicular germ cell cancer between 1987 and 1989, and age-matched controls. Data were collected on 502 cases, 346 case mothers, 975 controls, and 522 control mothers. Surrogate measures for age at puberty included age at starting to shave, appearance of hair, growth spurt, and voice change.
A protective effect of later puberty was evident for all four measures of puberty as reported by both subjects and mothers, and greater protection was conferred when the greatest number of later puberty events were reported. Risk associated with earlier puberty was inconclusive.
As age at puberty is decreasing in the population, the proportion of boys experiencing the protective effect of later puberty may be diminishing. This may help explain the increasing incidence of testicular cancer.