For men with prostate cancer who are on active surveillance (monitoring instead of immediate treatment), low testosterone levels are linked to a higher chance that their cancer will progress to a more aggressive grade.

Low Testosterone Levels and Grade Group Progression Among Localized Prostate Cancer Patients on Active Surveillance: A Retrospective Cohort Study.

·Cohort Study·Human·2026

This study found that men with low testosterone were 61% more likely to develop a more aggressive prostate cancer (Grade Group 3 or higher) while on active surveillance, which supports the idea that low testosterone is linked to higher risk of cancer progression.

Low serum total testosterone level as a predictor of upstaging and upgrading in low-risk prostate cancer patients meeting the inclusion criteria for active surveillance

·Cohort Study·Human·2017

This study found that men with low-risk prostate cancer who had low testosterone levels were more likely to have aggressive cancer when examined after surgery, suggesting that low testosterone is linked to a higher chance of cancer progression, which supports the claim.

Can testosterone therapy be offered to men on active surveillance for prostate cancer? Preliminary results

·Cohort Study·Human·2016

Men with low testosterone who took testosterone supplements did not have a higher chance of their prostate cancer getting worse compared to those who didn't take testosterone, so low testosterone might not actually increase risk.

Oncological safety of testosterone replacement therapy in men with localised prostate cancer: a systematic review of observational studies

·Systematic Review·Review·2025

The study looked at men with low testosterone who were monitoring their prostate cancer, and found that giving them testosterone didn't make their cancer more likely to get worse, suggesting that low testosterone isn't actually linked to higher risk of progression.