ABSTRACT
BACKGROUND/AIMS: FDG-PET is widely used for the evaluation of cancer patients. FDG-PET is usually employed for a staging of colorectal cancer and for the early detection of postoperative recurrence of cancer. Areas of focal uptake that suggest colonic lesions, including benign adenoma, may be seen on an FDG-PET image. This study evaluated the characteristics of colonic adenoma as detected by FDG-PET. METHODS: 60 subjects (M/F: 30:30, mean age: 55+/-11) who underwent both PET study and colonoscopy were enrolled and their data were retrospectively analyzed. RESULTS: A total of 50 lesions of colonic adenoma (3~35 mm) were found in 17 subjects by colonoscopy. Compared with the colonoscopic findings, FDG- PET had a positive predictive value of 52.9% and a negative predictable value of 81.4%. The positive rate increased with the size of the colonic adenoma (15 mm, 100.0%; > or =10 mm, 82.4%; <5 mm, 0.0%) and with the protruded type of polyp (sessile, 25.0%; subpedunculated, 47.7%; pedunculated, 90.9%). CONCLUSIONS: FDG-PET positive colonic lesions should raise a concern for not only possible malignancy, but also for the large sized or malignant transforming colonic adenoma.