1. Bone Cancer

2. Development of Bone Cancer • Advancing age and a previous history of cancer are the two most important risk factors for cancer • Primary bone cancer is uncommon; however, the skeleton is the most common organ affected by metastatic cancer. • Primary cancers of the breast, prostate, thyroid, lung, and kidney commonly metastasize to the bone. • Cancer is more likely to metastasize to the vertebrae, pelvis, ribs, skull, proximal femur, sternum, or cervical spine. • Bone pain in the lumbar spine or proximal femur can refer pain to the knee.

3. Common Risk Factors • Age over 50 years • Ethnicity: racial minorities and ethnic groups are at an elevated risk • Family history • Environment and lifestyle

4. Presentation of Bone Cancer • Deep pain • Poorly localized • Pain increases with activity • Pain description: burning, aching, stabbing • Pain is cyclic and progressive until it becomes constant • Decreased tolerance to weight bearing • Antalgicpatterns. • Bone pain does not respond well to physical agents • Soft tissue swelling • Pathologic fractures • Hypercalcemia • Back or rib pain

5. Additional Signs and Symptoms • Unexplained changes in appetite • Unexplained weight gain or loss of 10% of total body weight within the last 4 weeks • Proximal muscle weakness • if the nerves are compressed • Change in two or more deep tendon reflexes • Palpable lump or mass • Pain present at night, unrelieved by change in position

6. Tests to Differentiate • Heel strike test • Pain reproduced is indicative of a fracture • Fractures can also be associated with tumors • Pain that subsides with salicylates is characteristic of an osteoidosteoma • Osteoidosteoma is a benign osteoblastic tumor that commonly occurs in the diaphysis of long bones • Occurs usually between ages 7 to 25

7. Recommendation • Refer to primary care physician for further testing

8. Reference • Siegenthaler, Walter. 2007. Siegenthaler’s Differential Diagnosis in Internal Medicine: From Symptom to Diagnosis. Georg ThiemeVerlag. Stuttgart, Germany. 1144 pages.