Bladder Cancer Recurrence Risk Lower in Metformin Users
The protective effect of the diabetes drug metformin among patients who undergo surgery for non-muscle invasive bladder cancer is dose dependent, according to a study.
|The following article is part of conference coverage from the 2017 American Urological Association meeting in Boston. Renal and Urology News' staff will be reporting live on medical studies conducted by urologists and other specialists who are tops in their field in kidney stones, prostate cancer, kidney cancer, bladder cancer, enlarged prostate, and more. Check back for the latest news from AUA 2017.|
BOSTON—Metformin use at the time of transurethral resection (TUR) of non-muscle invasive bladder cancer (NMIBC) is associated with improved recurrence-free survival, according to study findings presented at the American Urological Association 2017 annual meeting. Results also showed that metformin doses of 2000 mg or more are independently associated with decreased recurrence risk.
In a study of 503 patients who underwent TUR for NMIBC, Timothy Rushmer, a fourth-year medical student at the University of Wisconsin in Madison, and colleagues found that, on multivariate analysis, diabetic patients on metformin at the time of TUR had a significant 49% and 40% decreased risk of disease recurrence compared with diabetic patients not on metformin and non-diabetic patients not on metformin, respectively.
The 5-year recurrence-free survival rate was 42.3% for diabetic patients on metformin compared with 9.7% among diabetics not on metformin, and 35.1% for non-diabetics not on metformin.
The study population had a median age of 70.6 years. The median time to recurrence was 15 months.
In a separate multivariate analysis, Rushmer's group found that patients taking 2000 mg or more of metformin at the time of TUR, compared with taking less than 2000 mg, had a significant 61% decreased risk of recurrence.
Rushmer T, Damodaran S, Abel EJ, et al. Improved recurrence free survival in NMIBC patients taking metformin demonstrates dose dependence. [abstract] J Urol 2017;197(4S):e178. Poster presented at the American Urological Association 2017 annual meeting in Boston on May 12, 2017. Poster MP15-19.