Fine-needle aspiration of primary osteosarcoma: a cytological-histological study

This study aims to determine the diagnostic accuracy of fine-needle aspiration (FNA) evaluation of primary osteosarcoma (OS) and to review diagnostic criteria and adjunctive methods that can contribute to a confident diagnosis of OS in cytological smears. We evaluated FNA smears of OS in 59 patients for the following: cytomorphology and occurrence of osteoid, usefulness of adjunctive methods in evaluation of FNA smears and correspondence of FNA to the clinical data, and the histological features of excised tumors. Reliable cytological criteria of malignancy were found in 49 smears of high-grade OS. These criteria, correlated with radiographic studies and complemented by ancillary techniques, allowed diagnosis of OS or suspicion of OS in 44 cases. An additional four smears were diagnosed as sarcoma and one case was diagnosed erroneously as being carcinoma metastasis. There were no false positive or false negative diagnoses. We conclude that FNA smears from high-grade OS have characteristic features, which together with clinical and radiological data and ancillary studies allow correct diagnosis in most tumors.