Critical Evaluation of Fine Needle Aspiration Cytology as a Diagnostic Technique in Bone Tumors and Tumor-like Lesions

Background: Though open surgical biopsy is the procedure of choice for the diagnosis of bone tumors,many disadvantages are associated with this approach. The present study was undertaken to evaluate the roleof fine needle aspiration cytology (FNAC) as a diagnostic tool in cases of bony tumors and tumor-like lesionswhich may be conducted in centers where facilities for surgical biopsies are inadequate.
Methods: The studypopulation consisted of 51 cases presenting with a skeletal mass. After clinical evaluation, radiological correlationwas done to assess the nature and extent of each lesion. Fine needle aspiration was performed aseptically andsmears were prepared. Patients subsequently underwent open surgical biopsy and tissue samples were obtainedfor histopathological examination. Standard statistical methods were applied for analysis of data.
Results:Adequate material was not obtained even after repeated aspiration in seven cases, six of which were benign.Among the remaining 44 cases, diagnosis of malignancy was correctly provided in 28 (93.3%) out of 30 casesand categorical diagnosis in 20 (66.67%) . Interpretation of cytology was more difficult in cases of benign andtumor-like lesions, with a categorical opinion only possible in seven (50%) cases. Statistical analysis showedFNAC with malignant tumors to have high sensitivity (93.3%), specificity (92.9%) and positive predictive value of96.6%, whereas the negative predictive value was 86.7%.
Conclusion: FNAC should be included in the diagnosticworkup of a skeletal tumor because of its simplicity and reliability. However, a definitive pathologic diagnosisheavily depends on compatible clinical and radiologic features which can only be accomplished by teamwork.The cytological technique applied in this study could detect many bone tumors and tumor-like conditions andappears particularly suitable as a diagnostic technique for rural regions of India as other developing countries.