Fine needle aspiration cytology and correlation with biopsy in lung lesions

Abstract

Introduction: Lung cancer is one of the leading cause of death worldwide. High mortality makes early diagnosis and treatment of utmost importance. Cytology plays an important role in the initial evaluation and diagnosis of these patients. Currently various sampling techniques are available to procure specimens for cytologic evaluation, which include exfoliative, abrasive cytology and fine needle aspiration cytology (FNAC). The aim of the study is to assess the role of CT/USG guided FNAC of lung and pleural lesions and correlate the findings with biopsy Methods: 82 patients with lung lesions were evaluated with USG/CT guided FNA and biopsy between January 2016 & July 2016. The findings of FNAC were correlated with the biopsy wherever available, in order to assess the reliability of a cytologic diagnosis of the various lung lesions on FNAC. The various differential diagnosis are also discussed. Results: The age group ranged from 19-84ys with a median age of 60 yrs, and a male predominance (92.6%). Majority of lesions involved the lung parenchyma. Benign, suspicious and malignant lesions accounted for 8.5%, 3.7% and 87.8% respectively. On classification, adenocarcinomas accounted for majority of the malignant lesions (34.1%) followed by squamous cell carcinomas (26.8%). 57 out of 82 patients underwent biopsy of the lung lesions. When the FNAC findings were correlated with the histopathological biopsy findings, 6.7 % (4) of cases did not correlate. Thus the sensitivity and specificity of the study were 84.2% and 100% respectively. Preoperative diagnosis of lung cancer detected by screening with CT could be reliably made by FNAC. Difficulty in classification occurs in carcinomas of high nuclear grade with prominent nucleoli, including poorly differentiated squamous cell carcinoma and large cell neuroendocrine carcinoma. Differentiating adenocarcinoma and squamous cell carcinomas could also be challenging at times. Conclusion: CT guided FNAC has emerged as a less invasive, cost effective, rapid and fairly accurate diagnostic aid in the evaluation of lung lesions. Correlation of the cytomorphologic features with the clinical presentation of the patient including radiologic imaging are absolutely critical in the accurate interpretations of respiratory cytology specimens.