The biopsy is a critical step in the evaluation of patients with suspected malignancies. The surgical approach in performing the biopsy can significantly affect the patient's future treatment options and prognosis. From July 1985 to July 1986, 63 patients were referred for evaluation by the Orthopaedic Oncology Service at Walter Reed Army Medical Center. Seven patients with primary musculoskeletal malignancies had biopsy or surgery prior to referral. In six patients this had an adverse impact on their treatment, resulting in amputation. Careful consideration of masses as potential malignancies should be undertaken prior to biopsy, and should the surgeon or the hospital be unable to provide definitive care for the patient, consideration should be given to early referral before biopsy.