Role of Rapid On-site Evaluation in CT-guided Fine Needle Aspiration Cytology of Lung Nodules

Objective: To prospectively investigate the value of rapid on-site evaluation (ROSE) in transthoracic fine needle aspiration cytology (FNAC) of patients with pulmonary nodules. Computed tomography (CT) -guided FNA is commonly employed for the diagnosis of lung lesions and the most common reason for not being able to provide a diagnosis in FNA is inadequacy of samples. Materials and Methods: This was a prospective study conducted in the departments of pathology and radiology of our cancer centre. This study had approval from the institutional review board and ethical committee of our institute. Fifty consecutive cases undergoing CT-guided transthoracic FNAC in our centre were included in the study. The smear submitted for ROSE was stained using toluidine blue stain. The specimen adequacy and diagnosis in ROSE was compared with that of the final cytology report, and the concordance regarding adequacy and diagnosis were noted. Results: Smears were adequate in 34 cases (68%) and inadequate in 16 cases (32%) Out of the 16 inadequate cases, 5 (31%) were converted to adequate due to the application of ROSE, thus increasing the adequate number of cases to 39 (78%). A diagnosis of malignancy was made in all 39 adequate cases. Sensitivity of ROSE in determining adequacy was 92% and specificity was 100%. The most common malignancy was adenocarcinoma in 26 cases. Pnemothorax occurred in 2 cases. No significant complications occurred in other cases. Conclusion: CT-guided FNA with ROSE is a safe and useful tool in the diagnostic work-up of lung cancer patients. A multidisciplinary approach along with onsite evaluation of adequacy will increase the diagnostic utility of cytology in lung lesions.