# Clinical Oncological Tolerance of Testosterone Replacement Therapy Over Two Years Among Patients With High-Risk or Very High-Risk Prostate Cancer Undergoing Radiotherapy

## TL;DR

This study found that testosterone replacement therapy for two years did not lead to cancer recurrence in high-risk prostate cancer patients who had completed radiotherapy.

## Contribution

The study provides new evidence on the oncological tolerance of TRT in high-risk prostate cancer patients post-radiotherapy.

## Key findings

- TRT for two years did not result in biochemical or clinical prostate cancer recurrence.
- PSA levels increased initially but remained stable after six months.
- Testosterone and hemoglobin levels increased significantly but stabilized over time.

## Abstract

Objective: Studies have demonstrated that testosterone replacement therapy (TRT) for patients with prostate cancer following curative local therapy does not significantly increase the biochemical and clinical recurrences of cancer. However, evidence on oncological tolerance of TRT for patients with high-risk prostate cancer is currently limited. This study assessed clinical oncological tolerance of TRT in patients with high- or very high-risk prostate cancer undergoing radiotherapy.

Methods: Patients with serum total testosterone (TT) levels <300 ng/dl and any hypogonadal symptoms were screened. Cases without definitive evidence of prostate cancer recurrence were considered as candidates for TRT based on serum prostate-specific antigen (PSA) levels below 0.2 ng/ml for more than 2 years after completing all radical treatment. All patients received testosterone enanthate intramuscularly every four weeks. Blood biochemistry, including PSA levels, was evaluated every three months after TRT. Serum TT levels were measured every six months. Radiological imaging was performed every year.

Results: A total of 20 patients were included in the study. At TRT initiation, the mean age of the patients was 74.1 years. The mean TT and PSA levels were 0.608 and 0.021 ng/ml, respectively. TRT was continued for a mean of 43.7 (3-132) months. Twelve cases (63%) could complete the two-year TRT. The serum PSA levels showed a significant increase for six months after TRT (p < 0.05) and did not change significantly until 24 months. The serum TT levels increased significantly at the six-month visit and remained stable until the 24th month. The hemoglobin levels significantly increased by the sixth month but remained unchanged thereafter. No cases showed biochemical and clinical recurrences of prostate cancer.

Conclusion: TRT for two years might be tolerated for cancer control among patients with high-risk prostate cancer who had undergone radiotherapy. Since this was a retrospective study without a control group, further prospective studies, including a large number of subjects and a control group, are required to reach a more definite conclusion.