Cytological profile in diagnosis of lung lesions and comparison with gold standard lung biopsy (TBLB)

Abstract

The diagnostics in field of lung pathology with advent of bronchoscopic modalities comprises of BAL, BB, TBNA and TBLB. As the detection of malignancy at the earliest has taken so much importance in terms of treatment, prognosis and life expectancy use of cytological bronchoscopic modalities have come to an age and has promised early, accurate diagnosis and better patient outcome. In India as cases of lung diseases continues to increase, the use of cytology has a special role and in particular neoplastic lesions, infectious diseases and in ILD cases. TBNA technique should be encouraged due to its superior sensitivity. This study of BAL, BB, TBNA was done during routine diagnostic bronchoscopies at Government tertiary care centre and comparing their results with TBLB as gold standard. The study consisted of clinically diagnosed / suspected cases of lung lesions. The BAL/TBNA/BB cytology and TBLB specimens were taken by the pulmonologist. The clinical, radiological and bronchoscopic data was assessed. Only the cases where BAL, BB, TBNA and TBLB were received simultaneously were included. Investigations done were complete blood count, random blood sugar, blood urea, serum creatinine, electrolytes, HIV evaluation and Chest X-ray/ CT. In our study of 200 cases, 62 were neoplastic and 109 non-neoplastic on and in 29 cases no abnormality was detected. Out of 62, 46 are of squamous cell carcinoma, 10 of adenocarcinoma and others were 06 in number. The non-neoplastic cases includes 06 cases of acute inflammatory lesions, 29 cases of Tuberculosis, 34 cases of Interstitial pneumonia, 6 cases of sarcoidosis, 1 case of fungal infection, and 17 cases of nonspecific inflammation. On combining TBNA with BAL and BB, overall sensitivity was 62.6% with total positive cases 114. For neoplastic lesions combined sensitivity for all BAL, BB and TBNA was 53.8% (n=62), and for non- neoplastic sensitivity was 73.9%. For assessing the level of agreement all cases of study reviewed by supervisor and κ value calculated was 0.75. This κ value of 0.75 suggests very good agreement with results of this study and validates the results of this study. The proposed protocol for cytopathological diagnosis includes use of all BAL, BB, TBNA and TBLB in suspected lung cases for accurate and early diagnosis for better and early treatment. Combination of these yields best sensitivity and accurate diagnosis. However biopsy remains the gold standard.