Incidence of prostate, colorectal and male breast cancers in relation with statins and testosterone replacement therapy: SEER-Medicare 2007-2015.

Dual use of statins and TTh was inversely associated with incident hormone-related cancers (HRCs) before 3 years of follow-up.

• The adjusted hazard ratio for dual users vs. neither users was aHR: 0.39 (95% CI: 0.35–0.44) before 3 years of follow-up.
• After 3 years of follow-up, the inverse association persisted but was attenuated (aHR: 0.74; 95% CI: 0.67–0.82).
• The study included 105,690 men aged ≥65 years identified using SEER-Medicare 2007–2015 data.
• Multivariable Time-varying Cox proportional hazards and Accelerated Failure Time (AFT) models were used.
• Greatest associations of HRC risk reduction were observed among dual users (statins plus TTh).

Dual use of statins and TTh was associated with lower risk of advanced stage HRC.

• Lower risk for advanced stage HRC was observed only in the <3 years follow-up period.
• This association was identified in the overall cohort of 105,690 men.
• The study categorized pre-diagnostic prescription use into four groups: neither users, statins alone, TTh alone, and dual users.

Joint inverse associations of statins and TTh were identified specifically for incident prostate cancer and aggressive prostate cancer.

• Similar joint associations were identified with incident PCa and aggressive PCa.
• These associations were observed across the full follow-up and specifically noted at <3 years of follow-up.
• The cohort included 82,578 White and 10,256 Black men identified from the SEER-Medicare dataset.

Joint inverse associations of statins and TTh were identified for incident colorectal cancer, including right- and left-sided CRC.

• Inverse associations were found for incident CRC and its specific right- and left-sided subtypes.
• These associations for specific CRC subsites were observed only at <3 years of follow-up.
• Findings from the AFT analysis were similar to those from the Cox proportional hazards models.

Inverse associations between dual use of statins and TTh and HRC risk persisted among White men, primarily at less than 3 years of follow-up.

• The study identified 82,578 White men in the SEER-Medicare cohort.
• Inverse associations among White men were observed mainly at <3 years of follow-up.
• Race-stratified analyses were performed to assess whether associations varied by race.

Inverse associations between dual use of statins and TTh and HRC risk persisted among Black men, particularly for high-grade HRC and at less than 3 years of follow-up.

• The study identified 10,256 Black men in the SEER-Medicare cohort.
• Among Black men, the inverse associations were observed for high-grade HRC and at <3 years of follow-up.
• The authors noted the sample of Black men was relatively smaller and called for larger samples in future studies.

Statins and TTh were each independently associated with reduced risks of HRC and specific cancer sites.

• Independent associations were observed for statins alone and TTh alone compared to neither users.
• These independent associations were noted at three years of follow-up overall, and among White and Black men.
• Pre-diagnostic prescription of statins and TTh was ascertained and categorized for the analysis.

The study population was drawn from SEER-Medicare data spanning 2007–2015 and included men aged 65 years and older.

• A total of 105,690 men were identified, comprising 82,578 White and 10,256 Black men.
• The study used a retrospective cohort design.
• Pre-diagnostic prescription of statins and TTh was the primary exposure of interest.
• The authors noted that male breast cancer site had limited representation, warranting further study.