FINE-NEEDLE ASPIRATION BIOPSY IN THE DIAGNOSIS AND MANAGEMENT OF BONE-LESIONS - A STUDY OF 450 CASES

BACKGROUND. Fine-needle aspiration (FNA) biopsy has proved to be a cos t-effective technique, with low complication risks and high diagnostic Value in distinguishing neoplastic versus nonneoplastic lesions in ma ny organs. This study was designed to determine the reliability, areas of diagnostic difficulty, and limitations of FNA in tile diagnosis of bone lesions encountered in a university-affiliated tertiary care hos pital. METHODS. The cytology of 450 FNA biopsies of bone lesions, perf ormed an 427 patients between 1979 and 1996, were reviewed. The result s were correlated with the corresponding histology when available, and with clinical follow-up, in an attempt to define the role of FNA in m anaging patients with bony lesions. RESULTS. The patients ranged in ag e from 5 to 94 years, with a male-to-female ratio of 1.25:1. The spine was the most frequency aspirated site (49%), followed by the ilium, s acrum, mandible, ribs, and femur. Three hundred and eighty-five aspira tes (86%) were adequate for evaluation, with 215 cases diagnosed cytol ogically as positive for malignancy, 11 cases as suspicious but not di agnostic of malignancy, and 2 cases as inconclusive. One hundred and f ifty-seven cases were interpreted as showing no evidence of malignancy . Metastatic carcinoma was present in 175 of the 215 malignant aspirat es, and 67% of these were adenocarcinomas. Forty cases were primary ma lignant bone neoplasms, including myeloma, lymphoma, Ewing's sarcoma, chondrosarcoma, ameloblastoma, chordoma, neurofibrosarcoma, and unclas sified high grade sarcoma, False-negative diagnoses were rendered in t en cases; however, on review, material representative of the bone lesi on was not present in six cases. Five cases were correctly diagnosed a s malignant but were misclassified with regard to the type of malignan cy. CONCLUSIONS. FNA biopsy of bone lesions is a reliable and easily p erformed diagnostic test for metastatic and primary bone tumors. False -positive results have major therapeutic implications, hence the signi ficance of the authors' conservative diagnostic approach, which result ed in a false-positive rate of 0.2%. Areas of difficulty were due to i nadequate sampling or misclassification with regard to the exact type of malignancy. The simplicity and accuracy of this procedure, which do es not require any surgical incisions (open biopsy or manipulation), s upports its important role in triaging and managing bone lesions with minimum risk or morbidity. (C) 1997 American Cancer Society.