Diagnostic utility of fine-needle aspiration cytology of lesions involving bone

Background: Fine-needle aspiration (FNA) is utilized in the diagnostic work-up of bone lesions in a number of institutions, either in isolation or in conjunction with core biopsy. We report our experience with FNA of bone-based lesions, including comparison of this approach with concurrent core biopsy specimens. Methodsl: Retrospective review over a 5-year period (2011-2015) revealed 233 cases of bone FNAs. Results: The most commonly encountered diagnosis was malignant neoplasm (160 cases, 68.7%); within this group of malignancies, 103 cases (64.4%) represented metastatic carcinoma. Benign lesions were encountered infrequently (9 cases, 3.9%). While 37 cases (15.9%) revealed no evidence of malignancy, 12 cases (5.2%) showed atypical findings, 3 cases (1.3%) demonstrated inflammatory conditions, and 12 aspiration biopsies were deemed nondiagnostic (5.2%). In 202 cases, concurrent core biopsies were performed following FNA and rapid on-site evaluation (ROSE). Comparison of the FNA and core biopsy diagnoses among malignant neoplasms revealed 19 diagnostic discrepancies, including 16 cases with a false-negative FNA (7.9% of all FNAs with concurrent core biopsy) and 3 cases with a false-negative core biopsy (1.5% of all cases with corresponding FNA). Conclusion: Our findings indicate that FNA of bone lesions is a useful diagnostic technique with high sensitivity, particularly when the cytologic findings are interpreted in conjunction with the core biopsy and pertinent clinical and radiologic findings. In addition, ROSE followed by open, dynamic communication with the performing radiologist leads to an extremely low rate of inadequate core biopsy specimens, resulting in optimal patient diagnosis and management.