Importance of Early Follow-up Colonoscopy in Patients at High Risk for Colorectal Polyps.
OBJECTIVE
Minimizing the polyp miss rate during colonoscopy is important for patients at high risk for colorectal polyps. We investigated the polyp miss rate and the factors associated with it in high-risk patients.


METHODS
The medical records of 163 patients who underwent follow-up colonoscopy between January 2001 and April 2010, which was within 9 months after a polypectomy, because the index colonoscopy had shown multiple (more than 3) adenomas or advanced adenoma were retrospectively reviewed. Miss rates were calculated for all polyps, for neoplastic polyps and for advanced adenomas. Factors associated with the miss rates in these patients, such as the location, shape and size of the polyp, were analyzed.


RESULTS
The miss rates for polyps, adenomas, adenomas <5 mm, adenomas ≥5 mm and advanced adenomas were 32.6%, 20.9%, 17.7%, 3.2%, and 0.9%, respectively. No carcinoma, except for one small carcinoid tumor, was missed. Flat shape and small size (<5 mm) were significantly associated with adenoma miss rate. The miss rate was significantly higher for flat-type advanced adenomas than for protruded-type advanced adenomas (27.7% vs 4.1%).


CONCLUSIONS
The polyp miss rate in patients at high risk for colorectal polyps was higher than expected. Efforts are needed to reduce miss rates and improve the quality of colonoscopy. Also, early follow-up colonoscopy is mandatory, especially in patients at high risk.
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Sung Taek
ST
Jung
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Dae Kyung
DK
Sohn
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Chang Won
CW
Hong
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Byung Chang
BC
Kim
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Ji Won
JW
Park
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Kyung Su
KS
Han
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Hee Jin
HJ
Chang
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Hyo Sung
HS
Choi
Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
Jae Hwan
JH
Oh
Colonoscopy; Colorectal neoplasms; Metachronous adenoma; Miss rate