Cytopathology of Pulmonary Lesions: A Tertiary Care Center Experience

Cytological evaluation of specimens from respiratory tract is the initial investigation in patients suspected to have pulmonary diseases. The various cytological specimens submitted for analysis include bronchoalveolar lavage, bronchial wash, brush smears, transbronchial needle aspiration, guided fine needle aspiration cytology (FNAC) smears and pleural fluid. Present study was undertaken to study the spectrum of lesions diagnosed by cytomorphological analysis of various cytological specimens.

Centrifuged and direct smears from received samples were stained with MGG and PAP stain. Special stains (ZN and PAS) were used wherever required. Cytohistological correlation was done wherever biopsy was available.

This study included 671 samples from 583 patients suspected clinicoradiologically of having a respiratory pathology. A male preponderance (65.87%) was noted with 73.59% of patients in age group 40-80 years. Cytological diagnoses were classified as non-diagnostic (14.90%), negative for malignancy (59.76%), specific benign lesions (5.22%), positive for atypical cells (3.87%) and malignant (16.25%). Tuberculosis (TB) was found in 17 cases. Adenocarcinoma (both primary and metastatic) was the commonest malignancy of the 99 cases positive for malignancy. Incidence of primary lung adenocarcinoma and squamous cell carcinoma were found to be equal.

Lung carcinoma is presently the leading cause of cancer deaths while TB is still a common cause of death in developing countries. Cytopathology has a definite role in diagnosis of malignant lesions and also contributes in diagnosis of unsuspected chronic infections. Cytological diagnosis is fairly accurate if the specimen obtained is adequate and representative.