<prompt> Which is the most common location of carcinoid tumor ?BronchusIleumRectumColon  <response>: Location of carcinoid tumors: Bronchus 27.9 , Ileum 14.9, Rectum 13.6 , colon 8.6 . So Ileum comes next to bronchus and first in GI tract. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 3058, Table 350-3 