Thirty one patients (51.7%) presented with bronchogenic carcinoma, while 16 patients (26.7%) had tubercular sequelae like persisting cavity, collapse, fibrosis, etc. Among the different co-morbid conditions and risk factors, the common associations included diabetes mellitus (DM), severe anaemia (Hb <9%), use of steroids, alcoholism and chronic carrier state of HBV. Here, GSTM1 is linked to diabetes mellitus.