OBJECTIVES - To determine, in the above populations, the bone mineral density as measured by Dual Energy X-ray Absorptiometry (DEXA) of the lumbar spine, proximal hip (total hip, femoral neck and trochanter), and non-dominant distal radius, to document biochemical markers of bone turnover, to document vertebral fractures and body height, to document other aspects of body composition including adipose tissue and muscle mass as measured by whole body composition densitometry, and to document other potential confounding factors predisposing prostate cancer patients to osteoporosis.