Objective: To evaluate the clinical and biochemical effects of long-acting testosterone undecanoate injections in men with prostate cancer treated with brachytherapy, as the use of testosterone therapy (TTh) in men with prostate cancer is highly controversial, with limited published safety data, particularly after brachytherapy treatment.
Patients and methods: In all, 20 men treated with brachytherapy for prostate cancer received TTh for symptoms of testosterone deficiency from February 2005 to August 2013. Symptoms of testosterone deficiency included low libido, erectile dysfunction, and fatigue. The mode of TTh was long-acting testosterone undecanoate injections in all cases. Sexual function was assessed by Sexual Health Inventory for Men (SHIM) questionnaire. Serum PSA and testosterone concentrations were recorded monthly for 3 months, then every 3 months for the first year, every 6 months for the second year, and annually then after.
Results: The mean (range) age was 62 (49-74) years and the mean (range) serum PSA level at the time of prostate cancer diagnosis was 6.2 (2-11.5) ng/mL. The Gleason score was 2 + 3 in one patient, 3 + 3 in 15 patients, 3 + 4 in three patients and 4 + 4 in one patient. In all, 15 men were stage T1c and five were T2a. The mean (range) baseline total testosterone concentration was 343 (200-592) ng/dL, and 6.9 (2.1-9.7) ng/dL for free testosterone. The mean SHIM scores improved with treatment from 16.1 at baseline to 22.1 with TTh (P = 0.002). There was a decrease in mean PSA level from baseline of 0.7 ng/mL before initiation of TTh to 0.1 ng/mL at last follow-up (P < 0.001), with a median (range) follow-up of 31 (12-48) months. There were no cases of prostate cancer progression or recurrence.
Conclusions: With a median of 31-months follow-up, long-acting testosterone injections in men with prostate cancer treated with brachytherapy produced significant clinical benefits. There were no cases of rising serum PSA, prostate cancer progression or recurrence.