Testosterone Therapy May Reduce Incidence and Severity of Prostate Cancer

Chicago—There are few data available on whether testosterone therapy in men with hypogonadism increases the incidence or severity of prostate cancer. Researchers in Canada found recently that the risk of prostate cancer diagnosis was decreased in men with long-term testosterone therapy [Wallis et al., Lancet Diab Endocrinol 2016;4:498].

German researchers Ahmad Haider, MD, and Karim Sultan Haider, MD, recently conducted a controlled registry study to assess the incidence and severity of prostate cancer in men on long-term testosterone therapy (T-group) compared with an untreated control group of untreated men with hypogonadism (control). Results were reported during a poster session at the 2017 ASCO Annual Meeting in a poster titled Prostate Cancer in 696 Hypogonadal Men with and without Long-Term Testosterone Therapy: Results from a Controlled Registry Study.

Four hundred symptomatic men with testosterone ≤350 ng/dL received testosterone underconoate 1000 mg every 3 months for up to 10 years; 296 hypogonadal men opted against testosterone therapy. Median follow-up was 8 years; the total observation time covered >5000 patient-years.

Measurements included prostate volume, prostate-specific antigen (PSA), weight, and C-reactive protein; digital rectal examination/transrectal ultrasound was performed prior to the initiation of treatment and again every 6 to 12 months. When indicated by the European Association of Urology guidelines, biopsies were performed.

In the T-group, prostate volume increased slightly but significantly by 2.41 mL (P<.001) and PSA increased by 0.22 (a nonsignificant increase). In the control group, prostate volume decreased slightly but significantly by –1.20 ml (P<.005) and PSA by ­–0.38 (P<.0001). In the T-group, weight dropped by 18.23% and increased 1.78% in the control group. There was a significant decrease in the T-group in C-reactive protein; there was no change in the control group.

Nine men in the T-group (2.3%) were diagnosed with prostate cancer compared with 15 (5.1%) in the control group. The incidence per 10,000 years was 29 in the T-group and 102 in the control group. Mean baseline age of men with prostate cancer in the T-group was 65 years; in the control group, mean baseline age of those with prostate cancer was 65.5 years. All of those diagnosed with prostate cancer underwent prostatectomy.

In the T-group, all but one patient had a Gleason score of ≤6, and all had a predominant Gleason score of 3. Tumor grade was G2 in all nine (100%) of those with prostate cancer; tumor stage was T2a in seven patients (78%) and T2b in two patients (22%). In the control group, all 15 patients had Gleason score >6; four men had a predominant Gleason score of 3, ten had a predominant Gleason score of 4, and one had a predominant Gleason score of 5. Tumor grade was G2 in seven patients (46.7%) and G3 in eight patients (53.3%); tumor stage was T2b in one patient (6.7%), T2c in one patient (6.7%), T3a in one patient (6.7%), T3b in seven patients (46.7%), and T3c in six patients (50%).

“In hypogonadal men, testosterone therapy may decrease prostate cancer incidence compared to controls. Prostate cancer was less severe in the T-group. Weight loss and reduced inflammation by testosterone therapy may have contributed to our findings,” the researchers said.

Source: Haider A, Haider KS. Prostate cancer (PCa) in 696 hypogonadal men with and without long-term testosterone therapy (TTH): results from a controlled registry study. Abstract of a poster presented at the 2017 American Society of Clinical Oncology Annual Meeting, June 5, 2017, Chicago, Illinois.