The purpose of the study was to determine the effect of type 2 diabetes mellitus (T2DM) on outcomes and toxicities among men with localized prostate cancer receiving definitive radiation therapy.
We performed a retrospective review of 3217 patients, from 1998 to 2013, subdivided into 5 subgroups: (I) no T2DM; (II) T2DM receiving oral antihyperglycemic agent that contains metformin, no insulin; (III) T2DM receiving nonmetformin oral agent alone, no insulin; (IV) T2DM receiving any insulin; and (V) T2DM not receiving medication. Outcome measures were overall survival, freedom from biochemical failure (BF), freedom from distant metastasis, cancer-specific survival, and toxicities. Kaplan-Meier analysis, log rank tests, Fine and Gray competing risk regression (to adjust for patient and lifestyle factors), Cox models, and subdistribution hazard ratios (sHRs) were used.
Of the 3217 patients, 1295 (40%) were low-risk, 1192 (37%) were intermediate-risk, and 652 (20%) were high risk. The group I to V distribution was 81%, 8%, 5%, 3%, and 4%. The median dose was 78 Gy, and the median follow-up time was 50 (range, 1-190) months. Group V had increased mortality (sHR, 2.1; 95% confidence interval [CI], 0.66-1.54), BF (sHR, 2.14; 0.88-1.83), and cause-specific mortality (sHR, 3.87; 95% CI, 1.31-11). Acute toxicities were higher in group IV versus group I (genitourinary: 38% vs. 26%; P = .01; gastrointestinal: 21% vs. 5%; P = 001). Late toxicities were higher in groups IV and V versus group I (12%-14% vs. 2%-6%; P < .01).
Men with T2DM not receiving medication and men with T2DM receiving insulin had worse outcomes and toxicities compared to other patients.
Clinical genitourinary cancer. 2016 Sep 08 [Epub ahead of print]
Nicholas G Zaorsky, Talha Shaikh, Karen Ruth, Pankaj Sharda, Shelly B Hayes, Mark L Sobczak, Mark A Hallman, Marc C Smaldone, David Y T Chen, Eric M Horwitz
Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA. Electronic address: ., Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, PA., Biostatistics and Bioinformatics Facility, Fox Chase Cancer Center, Philadelphia, PA., Department of Endocrinology, Fox Chase Cancer Center, Philadelphia, PA., Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, PA.