Percutaneous Fine Needle Aspiration Biopsy for the Intrathoracic Lesions: What is the Meaning of Non-Diagnostic Results?

ABSTRACT

PURPOSE: To know what is the meaning of non-diagnostic results of fine needle aspiration biopsy (FNAB) and whether repeated aspiration is needed or not in those situations. MATERIALS AND METHODS: We reviewed 1845 patients who underwent FNAB from 1997 to 2001. Non-diagnostic results of the first FNAB were divided into four groups insufficient number of cells, inflammatory cells, necrotic debris and atypical cells. We analyzed final diagnosis of 531 patients who had non-diagnostic results from the first FNAB. Among them, 207 lesions were re-biopsied because of clinical and radiologic suspicion of malignancy. The diagnostic yield of repeated FNAB was analyzed and compared with the results of the first FNAB. RESULTS: Among 255 cases with "inflammatory cells only" results, 120 cases were confirmed benignancy on follow-up. Twenty nine of 50 atypical cells (58%) were malignant on follow-up. One hundred one of 207 repeated FNAB resulted in the non-diagnostic reports, and 106 of 207 repeated FNAB were diagnosed as specific diagnosis. Among thirty lesions showing atypical cells on the repeated FNAB, 22 (73%) were identified as malignant neoplasms. CONCLUSION: When the specimen of FNAB shows atypical cells, the possibility of malignancy is very high. When the results of FNAB is non-diagnostic in the cases with clinical and radiological suspicion of malignancy, repeated FNAB procedures should be seriously considered and will be helpful for accurate specific diagnosis.