6 [16]. Osteoblasts produce cytokines including IL-6 that appear to lead to androgen-independent induction of PSA genes [17]. Increases in PSA may lead to greater production of endothelin-1, a protein that stimulates osteoblasts and inhibits osteoclasts in the presence of androgen-insensitive prostate cancer cells [18]. All of the above factors may explain why spine BMD may be higher in men with elevated PSA. Of note, Vitamin D levels were fairly replete in both groups of men, those with and without fractures. This is likely because the Urology Clinic at the Dallas VAMC often empirically starts Calcium plus Vitamin D 500 mg/250 U replacement twice a day before we see men in the Osteoporo- sis clinic. Limitations of our study include the small sample size, retrospective data collection, and possible selection bias from inclusion criteria. Based on prior studies discussed above, one would expect BMD and fracture risk to be associated with testosterone levels and the duration of ADT. However, we did not ﬁnd it in our study. The cross- sectional nature of the study is not optimal for evaluating predictors of fracture since fractures are already present at the time the variables are assessed. Our inclusion criteria likely generated some selection bias due to the inclusion criteria of height loss. A future study could include subjects without height loss to compare groups with or without height loss. The range of height loss was relatively small with over 50% of subjects with height loss of 2 inches or less. Including BMD of distal 1/3 radius has been shown to increase sensitivity of DXA scans in detecting osteoporosis [3] but is not included in routine DXA scans at DVAMC. Going forward it would be important to study prospec- tively if the FRAX calculator is a precise predictor of fractures in men with prostate cancer on ADT. 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