The treatment of cancer can have a negative influence on bone metabolism. This can result in the development of early osteoporosis or the aggravation of existing osteoporosis, with an increased risk of fractures. Depending on the duration and type of cancer therapy, prophylactic or therapeutic measures against osteoporosis may become necessary. The risk of osteoporosis may be assessed by screening with osteodensitometry, among other methods. Effective treatment is possible, for example with bisphosphonates.