Benign and malignant tumors of bone often have common musculoskeletal manifestations mimicking rheumatic disorders. The detection and resolution of mimicking symptoms require knowledge, skills, and a problem-solving attitude for musculoskeletal disorders. Before engaging in an extensive investigation, a careful history and full physical examination must be done. This review addresses the recent literature from June 2001 to May 2002 on musculoskeletal manifestations of benign and malignant tumors of bone using "red flag" rubrics: nonspecific pain pattern, atypical soft-tissue or bony swellings, pathologic fracture, spinal paresis, osteolytic x-ray findings, and unexpected results of laboratory tests. Early diagnosis (appropriate use of imaging techniques) and multidisciplinary management have improved considerably the survival of patients with primary malignant bone disease (eg, osteosarcoma). For some benign bone tumors (eg, osteoid osteoma), interstitial laser photocoagulation is now the treatment of choice with a success rate comparable with that of other treatments.