Later puberty onset protective against testicular cancer
medwireNews: Males who undergo puberty late appear to have a lower than average risk for developing testicular cancer, report scientists, who emphasize that early puberty is not associated with an increased cancer risk.
They write in the International Journal of Andrology: "Our finding of a decreased risk of testicular cancer in association with late puberty has plausible biological explanations."
The first, simpler explanation relates to the period at risk for testicular cancer - almost no cases of testicular cancer occur between 2-3 years of age and age 15 years, suggesting that the period at risk starts with puberty.
A second possible explanation is that testicular cancer and age at puberty share genetic factors or postnatal risk factors, they explain, such as childhood nutrition, childhood obesity, and exposure to specific chemicals.
"Thirdly, if puberty represents a window of susceptibility, a change in age at puberty might imply a change in the type and level of exposures occurring during that time window," the researchers add.
The team, led by Milena Maule, from the University of Turin, Italy, searched the PubMed database in order to perform a meta-analysis of the effect of age at puberty on testicular cancer risk, identifying 12 studies that met the inclusion criteria and eight that were retained for the final meta-analysis.
The researchers found that, compared with individuals who started shaving at the same age as their peers, late shaving was linked to an odds ratio (OR) of testicular cancer of 0.84, while early shaving was associated with an OR of testicular cancer of 0.98.
Compared with individuals whose voices changed at the same age as peers, the OR of testicular cancer among those whose age at voice change was older was 0.87, while that for individuals whose voice changed earlier was 1.04.
Late-onset puberty was associated with an OR of testicular cancer of 0.67 when compared average onset, while early-onset puberty was linked to an OR of 0.89 compared with the norm. When comparing late age at puberty with early or average age at puberty, the OR was 0.81.
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By Liam Davenport, medwireNews Reporter