Diabetes mellitus, race and the odds of high grade prostate cancer in men treated with radiation therapy.
OBJECTIVE
Black men present more frequently with high grade prostate cancer and are more likely to have diabetes mellitus. We evaluated whether there is an independent association between diabetes mellitus and the risk of high grade prostate cancer in men diagnosed with prostate cancer and treated with radiation therapy.


METHODS
A polychotomous logistic regression analysis was performed to evaluate whether a diagnosis of diabetes mellitus was associated with the odds of Gleason score 7 or 8-10 prostate cancer in a cohort of 16,286 men, adjusting for black race, advancing age, prostate specific antigen and digital rectal examination findings.


RESULTS
Black men (adjusted OR 1.84, 95% CI 1.08-3.13, p = 0.024) and nonblack men (adjusted OR 1.59, 95% CI 1.33-1.89, p <0.001) with diabetes were more likely to have Gleason score 8-10 vs 6 or less prostate cancer than nondiabetic men. However, this was not true for Gleason score 7 vs 6 or less prostate cancer. Black race was significantly associated with Gleason score 7 vs 6 or less prostate cancer in men without and with diabetes (adjusted OR 1.38, 95% CI 1.17-1.63, p <0.001 and 1.61, 95% CI 1.17-2.21, p = 0.003, respectively). Black race was also associated with Gleason score 8-10 vs 6 or less prostate cancer in men without and with diabetes (adjusted OR 1.36, 95% CI 1.01-1.83, p = 0.04 and 1.58, 95% CI 0.98-2.53, p = 0.06, respectively).


CONCLUSIONS
In a cohort of men undergoing radiotherapy for prostate cancer the diagnosis of diabetes mellitus was significantly associated with an increased risk of being diagnosed with Gleason score 8-10 prostate cancer independent of black race.
Harvard Radiation Oncology Program and Department of Radiation Oncology, Brigham and Women's Hospital and Dana Farber Cancer Institute, Boston, Massachusetts 02215, USA. tmitin@partners.org
Timur
T
Mitin
Ming-Hui
MH
Chen
Yuanye
Y
Zhang
Brian J
BJ
Moran
Daniel E
DE
Dosoretz
Michael J
MJ
Katin
Michelle H
MH
Braccioforte
Sharon A
SA
Salenius
Anthony V
AV
D'Amico
D001741:Black or African American; D048909:Diabetes Complications / Q000453:epidemiology*; D006801:Humans; D008297:Male; D060787:Neoplasm Grading; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000532:radiotherapy*