Background. Cancer patients experience osteoporosis resulting from accelerated loss of bone mineral density (BMD) caused by their treatment. Such bone loss greatly increases the risk for fracture and can have other serious effects on quality of life.Methods. In the current report, the author focuses on studies of cancer therapy-associated bone loss, its prevalence and pathogenesis, and resulting clinical impact. Options for management and prevention are also reviewed, including treatment guidelines where available.Results. A variety of cancer therapies, including hormonal therapy, chemotherapy, and glucocorticoids, affect gonadal hormone production, which increases bone resorption and decreases BMD. Such bone loss occurs more rapidly and to a greater degree than normal age-related osteoporosis, increases the risk for fracture