Objectives. - Percutaneous biopsy is widely used for the diagnosis of primary and secondary bone malignancies. The primary objective of this study was to evaluate the contribution of percutaneous biopsy to the definite diagnosis in patients with suspected bone tumor. The secondary objective was to assess the potential diagnostic benefits of a second percutaneous biopsy when the first failed to provide the diagnosis.

Methods. - We retrospectively reviewed 108 percutaneous biopsies of bone lesions in 89 patients admitted to our rheumatology department from January 1994 to December 2001. There were 61 men and 28 women with a mean age of 59 years. The biopsies were done under computed tomography guidance in 68 patients and fluoroscopy in 21 patients.

Results. - The diagnostic yield of percutaneous biopsies was 68.5% overall and was significantly higher in patients with metastatic bone disease (100%) than in patients with primary tumors (83%) or hematological malignancies (58%) (P = 0.0004 and P < 0.0001, respectively). Yields were higher for peripheral lesions (85%) than for vertebral (65%) and pelvic (60%) lesions. Yields were 87% for lytic lesions, 66% for sclerotic lesions, and 50% for mixed lesions. When soft tissues were sampled, the yield was 100%, as compared to 86% for biopsies composed only of bone.

Conclusion. - Percutaneous biopsy of suspected bone tumors is a safe and inexpensive procedure that consistently ensures the diagnosis of bone metastases. The diagnostic yield is lowest in patients with bone lesions caused by hematological malignancies. When two biopsies fail to provide the diagnosis, further biopsies are unlikely to be helpful.