Cytologic diagnosis of osseous lesions: A review with emphasis on the diagnosis of primary neoplasms of bone

Fine‐needle aspiration has been utilized as the initial diagnostic technique at a large number of body sites for over three quarters of a century. As early as the 1930s, fine‐needle aspiration (FNA) was used to investigate lesions of the musculoskeletal system. In many early reports, FNA was most frequently and successfully used for the diagnosis of metastatic disease to bone. Less emphasis was placed on its utility for the investigation of primary neoplasms of bone and soft tissue. Current utilization of FNA continues to de‐emphasize its application to the diagnosis of primary lesions of the musculoskeletal system. Recent advances in imaging techniques, immunohistochemistry, and molecular diagnostics along with an increasing familiarity among pathologists with the cytologic appearance of primary osseous tumors has led to reevaluation of the technique for investigation of these tumors. The diagnostic accuracy of FNA along with its relatively low cost and high degree of safety makes it a desirable technique for the investigation of primary lesions of the musculoskeletal system. This article reviews issues of diagnostic accuracy, optimal practice procedures, and benefits of the technique including cost reduction. The article will review criteria for selection of appropriate tissue targets for FNA to reduce the number of unsatisfactory specimens. Cytomorphologic features of the more common primary neoplasms of bone will be summarized along with recommendations for the utilization of immunohistochemistry and molecular diagnostics in the work‐up of primary neoplasms of bone. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.