The Relationship Between Testosterone Therapy and Cancer: What You Need to Know

PHYSICIAN-REVIEWED TRT SAFETY EDUCATION

Medically reviewed by Dr. Timothy Mackey
Medical Director, NovaGenix · Updated September 2026

For the prostate-specific evidence and monitoring discussion, read Does Testosterone Therapy Cause Prostate Cancer?

Testosterone Replacement Therapy (TRT) has become an increasingly popular treatment for men experiencing symptoms of low testosterone, such as decreased libido, fatigue, and muscle loss. However, concerns about the potential link between TRT and cancer, particularly prostate cancer, have been a topic of debate for many years. This article looks at the relationship between testosterone therapy and cancer, examining the current understanding, historical context, and the importance of regular monitoring and personalized treatment approaches.

Historical Concerns About Testosterone and Cancer

Historical concerns about testosterone and prostate cancer should be distinguished from current evidence and from treatment in men with an existing cancer diagnosis. Research in carefully screened men is reassuring, but it does not establish that TRT has no effect on every patient’s cancer risk or that treatment is appropriate for all cancer survivors.

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Current Understanding of TRT and Prostate Cancer

The TRAVERSE prostate-safety analysis included 5,204 men in its analysis population. Prostate-cancer events were uncommon and did not differ significantly between testosterone and placebo groups. PSA rose more with testosterone, and men at higher baseline prostate risk were excluded. These findings do not prove cancer prevention, equal risk in every population, or lifelong safety.

Key Studies and Findings

• After prostate-cancer treatment: The AUA guideline states that evidence is inadequate to quantify the risk-benefit balance of TRT in men with a history of prostate cancer. Selected patients may be considered after specialist assessment and shared decision-making, but prior treatment does not establish that TRT is universally safe.
• Observational Studies: Large-scale observational studies have also found no strong evidence that TRT is associated with an increased risk of prostate cancer. These studies take into account various factors, including age, baseline testosterone levels, and comorbidities.
• Evidence reviews: Combining studies can help assess patterns, but conclusions remain limited by study size, patient selection, cancer-event counts and follow-up. A nonsignificant result is not proof that risk is absent.

Monitoring Prostate Health During TRT

Prostate assessment should reflect age, risk factors, symptoms and shared decision-making. Baseline and follow-up PSA testing and examination may be appropriate, with abnormal findings evaluated rather than dismissed as a routine treatment effect. See TRT and prostate monitoring.

Prostate-Specific Antigen (PSA) Test

The PSA test measures the level of PSA, a protein produced by the prostate gland, in the blood. Elevated PSA levels can indicate prostate inflammation, enlargement, or cancer. Regular PSA testing helps in tracking any changes in PSA levels over time, providing valuable information for healthcare providers to assess prostate health.

Digital Rectal Exam (DRE)

The DRE involves a healthcare provider manually examining the prostate gland through the rectum to detect any abnormalities, such as lumps or enlargement. This physical examination complements the PSA test and provides additional information about prostate health. The clinician determines whether examination or further investigation is appropriate; no single examination rules out prostate cancer.

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TRT and Other Types of Cancer

Breast Cancer

Gynecomastia is enlargement of breast tissue and is not itself a diagnosis of breast cancer. A new breast lump, nipple discharge or other concerning change warrants evaluation. The Endocrine Society recommends against starting TRT in men with breast cancer. Prostate-trial findings should not be used as proof of breast-cancer safety.

Hematologic Cancers

Evidence about prostate outcomes cannot establish the risk of leukemia, lymphoma or other hematologic cancers. This article does not establish a protective effect or a zero-risk conclusion for these diseases. A cancer history should be discussed with the treating specialists.

Testicular Cancer

Testicular cancer and testicular shrinkage during TRT are different issues. Research focused on prostate outcomes cannot resolve testicular-cancer risk. A new testicular lump or change needs medical assessment. Men treated for testicular cancer may need evaluation for hormone deficiency, with care coordinated through their treating clinicians.

As always, it’s important to consider the following points:

Underlying conditions: Other illnesses and a history of cancer can affect treatment decisions and monitoring. Tell the clinician about new symptoms between scheduled visits.

Hormone suppression and fertility: TRT can suppress natural testosterone and sperm production. Testicular size does not establish fertility, and hCG should not be presented as a guarantee against shrinkage or infertility during TRT. See testicular changes during treatment.

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General Cancer Risk and TRT

Cancer risk must be considered by cancer type and individual history. Reassuring findings from selected prostate studies should not be generalized to all cancers, every patient or lifetime exposure.

Long-Term Studies and Research

Long-term studies and ongoing research are essential to fully understand the potential risks and benefits of TRT. These studies help to identify any long-term trends or emerging concerns related to TRT and cancer risk. By continuously updating medical knowledge, healthcare providers can make informed decisions and provide the best possible care for their patients.

The Importance of Regular Monitoring and Personalized Treatment

Treatment decisions require a discussion of the evidence and its limits, together with the patient’s diagnosis, medical history and goals. Monitoring can identify concerns but cannot guarantee cancer prevention or early detection of every cancer.

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Personalized Treatment Plans

Every patient is unique, and the decision to undergo TRT should be based on a comprehensive assessment of individual needs, health status, and risk factors. Personalized treatment plans take into account many factors such as:

• Baseline testing: Suspected testosterone deficiency requires symptoms or signs and repeat appropriately timed measurements. Routine testosterone screening of every healthy young man is not recommended by the Endocrine Society. See testing before treatment.
• Symptom Severity: The severity of symptoms, such as fatigue, low libido, and muscle loss, guides the need for TRT and the expected benefits. Some people experience different symptom severity and others respond differently to treatment. The fact is, we’re all unique and need to be treated by our physicians as such.
• Medical History: A thorough review of medical history, including any history of cancer or other health conditions, is crucial in assessing the suitability of TRT. A doctor must take into account a patient’s entire medical history prior to starting a patient on TRT/HRT.
• Lifestyle Factors: Lifestyle factors, such as diet, exercise, and smoking status, can influence treatment outcomes and should be considered when developing a personalized TRT plan. Small changes can have a big impact in a positive way.

Regular Monitoring and Follow-Up

Follow-up helps the clinician assess response, review adverse effects and decide whether treatment should continue or change. It cannot establish that all health risks are absent. Discussions should cover symptoms as well as laboratory findings.

• Assess Treatment Efficacy: Regular evaluations will help determine whether TRT is effectively addressing symptoms and improving quality of life and if not, see what changes can be made to optimize outcome and results.
• Monitor prostate health: Follow the agreed screening and monitoring plan and evaluate concerning changes. Screening does not detect every cancer or guarantee prevention.
• Adjust Dosage: TRT dosages may need to be adjusted over time based on individual response and changing health needs. What works now may not work in the future so regular monitoring and consultations to discuss symptom relief is important for both patient and physician.
• Address Side Effects: Regular follow-up allows for the timely identification and management of any side effects or complications. Lab work alone can only tell the doctor so much. Understanding how the medication works through discussing how you feel with the provider and whether the symptoms have been addressed is required to optimize outcomes.

Proactive Management Strategies

Proactive management strategies help to optimize the benefits of TRT while minimizing potential risks. These strategies include:

• Healthy lifestyle: Physical activity, balanced nutrition, smoking cessation and avoiding excessive alcohol support general health. They should not be presented as guaranteed ways to raise testosterone or prevent treatment-related problems.
• Education and Awareness: Providing patients with education about TRT, its potential risks and benefits, and the importance of regular monitoring empowers them to make informed decisions. Too often, we have patients come in with information they found online from various sources and more often than not, it’s more harmful than helpful. Talk to a real physician for proper guidance.
• Collaboration with Specialists: Collaborating with specialists, such as endocrinologists and urologists or HRT specialists, ensures comprehensive care and expert guidance in managing TRT. Not all doctors are knowledgeable in hormone replacement therapy.

TRT and cancer require individualized assessment. Current prostate findings are reassuring within the populations studied, while important uncertainties remain for longer treatment and different cancer histories. A patient should understand those limitations before treatment. For an evaluation, contact NovaGenix or call 561-277-8260.

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Additional reference: Endocrine Society testosterone guideline.