From the article:
A total of 1,023 patients on T[estosterone] therapy were followed for up to 17 years with a median follow-up of approximately 5 years. Two study cohorts of 261 (cohort 1) and 340 (cohort 2) men were treated by urologists since 2004 and a third cohort of 422 men was treated at an academic andrology center since 1996. Hypogonadism was diagnosed if testosterone was ≤12 nmol/L [345.82 ng/dL] and if other symptoms were present, such as erectile dysfunction, fatigue, depression, or unfavorable changes in body composition (gaining of fat mass and waist circumference despite physical activity). If no contraindications were present, all were started on T therapy.
There were six (2.3%) diagnoses of PCa [prostate cancer] in cohort 1, there were five (1.5%) diagnoses of PCa in cohort 2, and all biopsies were negative in cohort 3. PCa incidence per 10,000 patient-years in cohorts 1 and 2 was 54.4 and 30.7, respectively, which is lower than 116 reported by the PLCO (Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial) and 96.6 reported by the ERSPC ( European Randomized Study of Screening for Prostate Cancer).
Investigators stress that if guidelines for T therapy are properly applied, it is safe in hypogonadal men.