Increased risk of cancer among azoospermic men

Objective To determine whether men with azoospermia are at an elevated risk of developing cancer in the years following an infertility evaluation. Design Cohort study. Setting United States andrology clinic. Patient(s) A total of 2,238 men with complete records were evaluated for infertility at a single andrology clinic in Texas from 1989 to 2009. Intervention(s) None. Main Outcome Measure(s) Cancer incidence was determined by linkage to the Texas Cancer Registry. Result(s) In all, 451 men had azoospermia, and 1,787 were not azoospermic, with a mean age at infertility evaluation of 35.7 years. Compared with the general population, infertile men had a higher risk of cancer, with 29 cases observed compared with 16.7 expected (standardized incidence rate [SIR] 1.7, 95% confidence interval [CI] 1.2–2.5). When stratifying by azoospermia status, azoospermic men had an elevated risk of cancer (SIR 2.9, 95% CI 1.4–5.4). Infertile men without azoospermia had a trend toward a higher rate of cancer (SIR 1.4, 95% CI 0.9–2.2). The Cox regression model revealed that azoospermic men had 2.2-fold higher cancer risk compared with nonazoospermic men (hazard ratio 2.2, 95% CI 1.0–4.8). Conclusion(s) Men with azoospermia have an increased risk of subsequently developing cancer, suggesting a possible common etiology between azoospermia and cancer development. Additional follow-up of azoospermic men after reproductive efforts end may be warranted.