Bronchial regions of interest (ROI's)suspected to be premalignant or malignant, identified during the bronchoscopy procedure, will be imaged using the OFDI system and catheter before biopsy is done. It is anticipated to obtain a minimum of 3 OFDI-biopsy correlated pairs from each study participant. An additional OFDI image and biopsy will be obtained from region's of normal interest (ROI's). It is expected that the experimental procedure will add less than 10 minutes to the total length of the bronchoscopy procedure, but a stopping rule will be instituted to ensure that the experimental procedure does not exceed 20 minutes.