['18-Fluorodeoxyglucose positron emission tomography (PET) is used clinically to detect recurrent colon cancer after surgical resection, but the sensitivity of PET for premalignant colon lesions and early stage colon cancer is not well defined.', 'In a prospective study, 45 patients with a total of 58 colonic neoplasms, including premalignant polyps, premalignant, flat lesions, and early stage cancers, were evaluated by PET.', 'The sensitivity of PET for cancer was 62% (8/13). PET detected 100% (7/7) of cancers 2 cm or larger but only 17% (1/6) of cancers smaller than 2 cm. PET detected 23% (3/13) of flat, premalignant lesions; 70% (7/10) of protruded, premalignant lesions 3 cm or larger; 38% (3/8) of protruded, premalignant lesions between 2 and 2.9 cm; and 14% (2/14) of protruded, premalignant lesions between 1 and 1.9 cm. There was no false-positive PET reading.'] Does 18-Fluorodeoxyglucose positron emission tomography have limited sensitivity for colonic adenoma and early stage colon cancer?