Background:   Bronchogenic carcinoma is the leading cause of cancer-related death worldwide in men and second most-common in women after breast cancer. Patients with bronchogenic carcinoma have poor prognosis with an overall survival rate of 10-15%. The early detection and accurate staging of bronchogenic cancer is crucial in planning the optimal treatment modalities and further management. Radiological imaging plays a critical role in the initial detection and diagnosis of lung cancer. Multi Detector computed tomography (MDCT) is the standard modality of choice for evaluating the lung cancer because of its better spatial resolution. CT has a role in identifying the lung nodules and characterizing them as benign or malignant.

Objectives: The study aims to assess the accuracy of Multi detector computed tomography in diagnosis and staging of Bronchogenic carcinoma. The study also intends to identify the various imaging characteristics types of bronchogenic carcinoma by MDCT.

Methodology:  This study was a descriptive study conducted on 80 subjects with clinically or radiologically suspicious bronchogenic carcinoma who were referred to department of radio diagnosis, Govt Medical college, Thrissur for undergoing contrast enhanced CT over a period of one year, and were selected based on inclusion and exclusion criteria. Pre and post contrast CT scans were performed. Lung lesions were analysed based on various variables and staging and provisional diagnosis were made and then correlated with histopathology. The data was managed using Microsoft Excel 2016 and statistical analysis was done with IBM SPSS Statistics v25. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of each characteristic as well as the combined values in comparison to histopathological findings were obtained.

Results: Majority of the patients belonged to 60 – 70 years age group (47.5%) with male predominance (77.5%).   About 66.8 % patients had history of smoking. Cough and dyspnea were the commonest symptoms. Most common radiological finding was central hilar mass lesion (57.5 %) followed by peripheral lesion in 42.5 %. Squamous cell carcinoma was the most common histopathological type (46.3%), followed by adenocarcinoma (22.5%) then small cell carcinoma (12.5%). The most common lobe affected by bronchogenic carcinoma was right upper lobe. The most common site of distant metastasis was adrenal gland (42.6%) followed by pleura (35.3%) and then liver (29.4%). Majority of the patients (69.1%) presented with TNM stage IV.

Conclusions:  Overall, CT had a sensitivity of 95.7% and specificity of 81.8%, positive predictive value of 97.1% and negative predictive value of 75 %. Multi detector computed tomography has high positive predictive value suggestive of great diagnostic accuracy in the evaluation of bronchogenic carcinoma. MDCT is a useful tool in the staging of Bronchogenic Carcinoma.

Keywords: Multidetector Computed Tomography (MDCT), Bronchogenic Carcinoma, Histopathology.

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Dr Akhil R Nambiar

Anjali, Chirakkal, Kannur 670011