A Closer Look at the Controversy
For decades, testosterone therapy was considered taboo for men with prostate cancer. The prevailing belief, based largely on historical assumptions, held that raising testosterone levels could fuel prostate cancer growth. Yet, in recent years, this narrative has begun to evolve slowly, and so has the science, but with caution.
What is Testosterone Therapy?
Testosterone replacement therapy (TRT) is used to treat men with low testosterone levels—a condition known as hypogonadism. Symptoms of low testosterone can include fatigue, low libido, erectile dysfunction, depression, decreased muscle mass, and osteoporosis. For many men, TRT improves energy, mood, cognition, bone density, and overall quality of life.
Risks in the General Population
In men without prostate cancer, TRT is generally considered safe when properly monitored. However, risks include elevated red blood cell counts (which can increase clot risk), acne, fluid retention, breast enlargement, and potential worsening of sleep apnea. The long-term cardiovascular effects are still debated, with some studies showing possible increased risks and others suggesting neutral or even beneficial effects.
The Old Fear: Testosterone “Feeds” Prostate Cancer
The concern that testosterone causes prostate cancer stems from early 20th-century studies and the observation that androgen deprivation shrinks metastatic prostate cancer. This led to a dogma: more testosterone equals more cancer. But more recent data suggest a more complex relationship.
Men on Active Surveillance (Watchful Waiting)
For men with low-risk prostate cancer under active surveillance, the decision to initiate TRT remains quite controversial. Limited studies suggest that testosterone may not significantly increase cancer progression in carefully selected patients, but long-term data are lacking.
Even while being treated for prostate with active surveillance, prostate cancer can progress without TRT. Therefore, men should be counseled very thoroughly, and if TRT is pursued, it should be done under close monitoring with frequent PSA tests, prostate imaging and prostate biopsy.
Post-Surgical Patients (Radical Prostatectomy)
Emerging studies suggest that in men who have undergone radical prostatectomy for localized prostate cancer—particularly those with undetectable PSA and no high-risk features—TRT may be safe. Several small cohort studies have shown no increased risk of biochemical recurrence in men who begin TRT after surgery. Nonetheless, these men should only be considered for TRT if they have clear symptoms of testosterone deficiency and a stable cancer status. Long term data is lacking beyond 7 years, and most studies are observational, subject to selection bias. Although the chance for PSA recurrence was low, proceed with caution nonetheless.
After Radiation Therapy
TRT after radiation presents a more nuanced risk. Some evidence suggests it may be safe, especially in men with low-risk disease and stable PSA levels. However, as with post-surgical cases, patient selection is key. The presence of high-grade or high-volume disease warrants extreme caution.
The Bottom Line
Testosterone therapy offers significant benefits to men suffering from the effects of low testosterone, but its use in men with prostate cancer must be approached very cautiously. Blanket prohibitions may no longer be justified, but careful selection, thorough counseling, and close monitoring are essential. As with many areas in medicine, the answer is not “yes” or “no,” but “it depends.”
