The burden of tuberculosis among patients with non-small cell lung carcinoma in a tertiary care center

Background Lung cancer and tuberculosis share similar risk factors, clinical spectrum, radiological features and it is difficult to differentiate but it is important to diagnose both conditions for targeted therapy and better outcome. Aims Our primary objective was to estimate the proportion of TB in primary biopsy proven non-small cell lung carcinoma (NSCLC) cases. Material & methods This prospective observational study was conducted in the Departments of Medicine/Pulmonary Medicine/Medical Oncology and Microbiology at the All India Institute of Medical Sciences, New Delhi for a period of 2 years (January 2020-December 2021). Patients with biopsy proven, primary non-small cell lung cancer were recruited and sputum samples were subjected to microbiological investigations to confirm tuberculosis. Comparison was done in two groups of lung cancer patients with confirmed TB (Group A) and without confirmed tuberculosis (Group B). Results Total 75 patients with biopsy proven, primary NSCLC were recruited and 16 % (12/75) were diagnosed with confirmed TB. Adenocarcinoma (36.48 %) and Squamous cell carcinoma (33.44 %) were the two predominant histopathological subtypes of NSCLC. About 57 (76 %) of them were found to be in stage IV of Lung cancer at initial presentation itself (75 % in group A & 74.6 % in group B; p value < 0.80). A majority of patients (11/12 cases; 91 %) of group A were males with a mean age of 59 +/- 7.5 years. The upper lobes of the lung were involved in 65 % (49/75) of the cases and showing a mass lesion on imaging (75 % in group A & 65 % in group B; p value < 0.52). Kaplan Meier survival revealed a median survival time of 11 months in subjects with only NSCLC and a median survival time of 4 months in the group with concomitant TB and NSCLC (p value < 0.44).