Computed tomography guided fine needle aspiration cytology of pulmonary mass lesions in a tertiary care hospital: A two-year prospective study

Background: Percutaneous or transthoracic fine needle aspiration cytology (FNAC) is a rapidly emerging diagnostic modality to assess the nature of radiologically demonstrated lung lesions. Aims: The present study was conducted to evaluate the usefulness of computed tomography (CT)-guided FNAC in the diagnosis of pulmonary mass lesions. Materials and Methods: The present prospective study was carried out on 74 cases of radiologically diagnosed pulmonary mass lesions involving the periphery of the lung parenchyma with strong clinical suspicion of pulmonary neoplasm. CT-guided transthoracic fine needle aspiration was performed and cytology smears were stained with May-Grόnwald-Giemsa (MGG) stain and conventional Papanicolaou (Pap) stain. Smears were broadly categorized into unsatisfactory, benign, suspicious of malignancy and malignant lesion. The cytological diagnosis was compared with subsequent histopathology report where it was necessary. Results: A total of 74 cases of pulmonary mass lesions were included in the present study, of which 58 were males (78.4%). The mean age of the patients was 51.6 years, but the mean age in case of malignant lesions was 62.5 years. Cough was the most common respiratory symptoms (100%) followed by weight loss (91.9%) and fever (62.2%). Maximum cases of benign lesions were chronic non-specific inflammation (10.8%; 8 cases) followed by tuberculosis (8.1%). Regarding the malignant categories, non-small cell carcinoma, not otherwise specified (NOS) (13.5%; 10 cases) was the most common malignancy followed by adenocarcinoma (10.8%; 8 cases), small cell carcinoma (8.1%; 6 cases) and squamous cell carcinoma (6.7%, 5 cases) respectively. All the 38 cases of malignant lesions were confirmed by histopathology. Out of 10 cases of non-small cell carcinoma, NOS 4 cases were diagnosed histopathologically as poorly differentiated adenocarcinoma, 2 cases as high grade squamous cell carcinoma, 2 cases as large cell carcinoma, 1 case as pleomorphic carcinoma and 1 case as adenosquamous carcinoma. Conclusion: CT guided FNAC is a less expensive, simple, fast and reliable method for diagnosis of pulmonary mass lesions.