@Article{,
AUTHOR = {Daniel Taussky, Felix Preisser, Pierre I. Karakiewicz, Derya Tilki, Carole Lambert, Jean-Paul Bahary, Guila Delouya, Robert Wistaff, Mikhael Laskine, Paul Van Nguyen, Madeleine Durand, Fred Saad},
TITLE = {Impact of diabetes and metformin use on prostate cancer outcome of patients treated with radiation therapy: results from a large institutional database},
JOURNAL = {Canadian Journal of Urology},
VOLUME = {25},
YEAR = {2018},
NUMBER = {5},
PAGES = {9509--9515},
URL = {http://www.techscience.com/CJU/v25n5/60740},
ISSN = {1488-5581},
ABSTRACT = {<b>Introduction:</b> Conflicting data exists on the influence of metformin on prostate cancer. We investigated the importance of metformin in patients treated with radiotherapy or brachytherapy.<br/>
<b>Materials and methods:</b> All patients from a large institutionalized database, treated for primary localized prostate cancer with either brachytherapy or external-beam radiotherapy ± androgen deprivation therapy were identified. Groups were compared by Kaplan–Meier analyses and Cox regression models. Multivariate analysis was adjusted for CAPRA-Score, type of treatment, and age.<br/>
<b>Results:</b> A total of 2441 patients with complete data was identified. Among them, 382 patients (16% of total) were diabetic. Two hundred eighty-one of the 382 diabetics (74%) were treated with metformin and 101 were treated with other anti-diabetic medication. Median follow-up was 48 months (interquartile range [IQR] 24-84). Two hundred eighteen patients (9%) died and 150 (6%) experienced biochemical recurrence (BCR). On unadjusted univariate analysis for BCR-free survival, metformin users showed a 50% reduction in BCR compared to non-metformin users. The results remained significant on multivariate analysis comparing diabetic metformin users to non-metformin users (diabetics and non-diabetics combined) (hazard ratio [HR] 0.5-0.6, p = 0.03-0.04), but lost significance when adjusting for cancer aggressiveness. On multivariate analysis, diabetics had worse overall survival (OS) than non-diabetics (HR 1.5, 95% confidence interval [CI] 1.08-2.06, p = 0.01), but diabetics on metformin fared better than diabetics not taking metformin (HR 0.5, 95% CI 0.26-0.86, p = 0.01).<br/>
<b>Conclusion:</b> Metformin use in this analysis appears to be associated with better BCR and OS. Larger datasets and prospective trials are warranted to validate these results.},
DOI = {}
}