A 65 yr old man is presenting with chronic cigarette cough which has recently changed its character. Tuberculosis and other infectious causes have been ruled out. What should be the next investigation:

In this scenario, the patient is suspected to be having bronchogenic Ca, because of the change in the character of chronic cigarette cough. The investigations to rule out are transbronchial biopsy during fibreoptic bronchoscopy or through a CT guided fine needle aspiration cytology (FNAC). Bronchoscopy should be the first choice in this instance. Ref: Textbook of Medicine By Vasan, R.S, Page 598 ; Harrison's Manual of Medicine, 2002, Page 59