Conventional vs. Liquid Based Cytology in Fine Needle Aspirates of Lung and Mediastinal Masses

Background: Lung cancer most common worldwide cancer, early diagnosis makes effective treatment in lung cancer. Liquid Based Cytology (LBC) for non-gynae specimens has gained popularity over conventional Cytology (CS) during last one decade because of increased sensitivity and specificity. Aim and objectives: To assess the diagnostic utility of LBC versus CS in fine needle aspirates of lung and mediastinal mass lesions. Compare cyto-morphological parameters in terms of adequacy, interpretation, concordance and diagnostic efficiency. Materials and Methods: Eighty -two cases suspected of lung or mediastinal mass lesions underwent imagine guided Transbronchial Needle aspiration (TBNA) or Trans Thoracic Needle aspiration (TTFNA). Fine needle passes were made for both conventional and LBC smears. All smears were examined and diagnosis was correlated in each case with histopathology as gold standard for final diagnosis. Results: Histopathology of 82 cases, 21 were non -neoplastic and 61 were malignant respectively.34 cases of adenocarcinoma, 15 cases of squamous cell carcinoma, 5 cases of adenosquamous cell carcinoma, 4 cases of small cell carcinoma, 1 cases of poorly differentiated 1 case of carcinoid and 1 cases of germ cell tumor. LBC were diagnosed 17 non -neoplastic and 54 were malignant respectively. 25 cases of adenocarcinoma, 11 cases of squamous cell carcinoma, 5 cases of adenosquamous cell carcinoma and 3 cases of small cell carcinoma, CS was diagnosed 4 non -neoplastic and 37 were malignant respectively. 24 cases of adenocarcinoma, 7 cases of squamous cell carcinoma, 4 cases of adenosquamous cell carcinoma and 2 cases of small cell carcinoma. Conclusion: Concordance of LBC with histopathology was found in higher proportion (72%) as compared to conventional smear (48.8%) (p=0.004), because percentage of adequacy for LBC (85.37%) was higher as compared to CS (56.1%) (P<0.001). The assessment of all the morphological parameters were predominantly equal in both methods except in few cases.