Importance of biopsy of new bone lesions in patients with previous carcinoma

Development of destructive bone lesions in a patient with a history of visceral carcinoma may be assumed to be metastatic disease. However, this assumption may lead to inappropriate treatment. We prospectively enrolled 50 patients (54 previous malignancies) from the South Australian Musculoskeletal Tumour Service with new metastases to bone after a previous diagnosis of localized visceral carcinoma. We performed biopsies on the new lesions and reviewed the patients' histories. The most common diagnosis was breast carcinoma (24 patients), followed by prostate (11 patients) carcinoma. The mean time between the first primary malignancy and the development of a bony lesion was 84 months (range, 30-83 years). The longest latency was with breast carcinoma and the shortest was with lung carcinoma. The bone abnormality was a new tumor in nine patients (15%), necrotic tissue in two patients, and normal tissue in one patient. A new tumor was most likely in patients with breast carcinoma (five patients) or prostate carcinoma (three patients). The bone lesion was always the same malignancy in patients with a history of renal or lung carcinoma. Failure to do a biopsy would have resulted in serious treatment errors in two of the three patients who had new tumors develop. We recommend performing biopsies for new bone lesions, especially if breast carcinoma was the previous primary malignancy.