The presence of large serrated polyps increases risk for colorectal cancer.
OBJECTIVE
There is evidence that serrated polyps (serrated adenomas and hyperplastic polyps) have different malignant potential than traditional adenomas. We used a colonoscopy database to determine the association between the presence of serrated colorectal polyps and colorectal neoplasia.


METHODS
We performed a multicenter observational study of 10,199 subjects who underwent first-time colonoscopies. Data collected on study subjects included age and sex and the location, size, and histology of polyps or tumors found at colonoscopy. Serrated polyps were defined as those diagnosed by the pathologists in the participating hospitals as a serrated lesion (a lesion given the term of "classical hyperplastic polyp," "traditional serrated adenoma," "sessile serrated adenoma," or "mixed serrated polyp"). Large serrated polyps (LSPs) were defined as those ≥ 10 mm.


RESULTS
There were 1573 patients (15.4%) with advanced neoplasia, 708 patients (6.9%) with colorectal cancer (CRC), and 140 patients (1.4%) with LSPs in our cohort. Multivariate analysis associated the presence of LSPs with advanced neoplasia (odds ratio [OR], 4.01; 95% confidence interval [CI], 2.83-5.69) and CRC (OR, 3.34; 95% CI, 2.16-5.03). The presence of LSPs was the greatest risk factor for CRC, particularly for proximal CRC (OR, 4.79; 95% CI, 2.54-8.42). Proximal and protruded LSPs were the highest risk factors for proximal CRC (OR, 5.36; 95% CI, 2.40-10.8 and OR, 9.00; 95% CI, 2.75-19.2, respectively).


CONCLUSIONS
The presence of LSPs is a risk factor for CRC, particularly CRC of the proximal colon.
Hiraoka
Sakiko
S
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Kato
Jun
J
Fujiki
Shigeatsu
S
Kaji
Eisuke
E
Morikawa
Tamiya
T
Murakami
Takatoshi
T
Nawa
Toru
T
Kuriyama
Motoaki
M
Uraoka
Toshio
T
Ohara
Nobuya
N
Yamamoto
Kazuhide
K
D000236:Adenoma / Q000175:diagnosis / Q000453:epidemiology*; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D003111:Colonic Polyps / Q000175:diagnosis / Q000453:epidemiology*; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000453:epidemiology*; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution