BACKGROUND/AIMS: Colonoscopic polypectomy is the best diagnostic and therapeutic tool to detect and prevent colorectal neoplasms. However, previous studies have reported that 17% to 28% of colorectal polyps are missed during colonoscopy. We investigated the miss rate of neoplastic polyps and the factors associated with missed polyps from quality-adjusted consecutive colonoscopies. METHODS: We reviewed the medical records of patients who were found to have colorectal polyps at a medical examination center of the Kangbuk Samsung Hospital between March 2012 and February 2013. Patients who were referred to a single tertiary academic medical center and underwent colonoscopic polypectomy on the same day were enrolled in our study. The odds ratios (ORs) associated with polyp-related and patient-related factors were evaluated using logistic regression analyses. RESULTS: A total of 463 patients and 1,294 neoplastic polyps were analyzed. The miss rates for adenomas, advanced adenomas, and carcinomas were 24.1% (312/1,294), 1.2% (15/1,294), and 0% (0/1,294), respectively. Flat/sessile-shaped adenomas (adjusted OR, 3.62; 95% confidence interval [CI], 2.40–5.46) and smaller adenomas (adjusted OR, 5.63; 95% CI, 2.84– 11.15 for ≤5 mm; adjusted OR, 3.18; 95% CI, 1.60–6.30 for 6–9 mm, respectively) were more frequently missed than pedunculated/sub-pedunculated adenomas and larger adenomas. In patients with 2 or more polyps compared with only one detected (adjusted OR, 2.37; 95% CI, 1.55–3.61 for 2–4 polyps; adjusted OR, 11.52; 95% CI, 4.61–28.79 for ≥5 polyps, respectively) during the first endoscopy, the risk of missing an additional polyp was significantly higher. CONCLUSIONS: One-quarter of neoplastic polyps was missed during colonoscopy. We encourage endoscopists to detect smaller and flat or sessile polyps by using the optimal withdrawal technique.
Academic Medical Centers ; Adenoma ; Colonoscopy* ; Colorectal Neoplasms ; Endoscopy ; Humans ; Logistic Models ; Medical Records ; Odds Ratio ; Polyps* ; Risk Factors*

PURPOSE: False-positive (FP) results of fecal immunochemical tests (FITs) conducted in colorectal cancer (CRC) screening could lead to performing unnecessary colonoscopies. Hemorrhoids are a possible cause of FP FIT results; however, studies on this topic are extremely rare. We investigated whether hemorrhoids are associated with FP FIT results. MATERIALS AND METHODS: A retrospective study was conducted at a university hospital in Korea from June 2013 to May 2015. Of the 34547 individuals who underwent FITs, 3946 aged ≥50 years who underwent colonoscopies were analyzed. Logistic regression analysis was performed to determine factors associated with FP FIT results. RESULTS: Among 3946 participants, 704 (17.8%) showed positive FIT results and 1303 (33.0%) had hemorrhoids. Of the 704 participants with positive FIT results, 165 had advanced colorectal neoplasia (ACRN) and 539 had no ACRN (FP results). Of the 1303 participants with hemorrhoids, 291 showed FP results, of whom 81 showed FP results because of hemorrhoids only. Participants with hemorrhoids had a higher rate of FP results than those without hemorrhoids (291/1176, 24.7% vs. 248/2361, 10.5%; p<0.001). Additionally, the participants with hemorrhoids as the only abnormality had a higher rate of FP results than those experiencing no such abnormalities (81/531, 15.3% vs. 38/1173, 3.2%; p<0.001). In multivariate analysis, the presence of hemorrhoids was identified as an independent predictor of FP results (adjusted odds ratio, 2.76; 95% confidence interval, 2.24–3.40; p<0.001). CONCLUSION: Hemorrhoids are significantly associated with FP FIT results. Their presence seemed to be a non-negligible contributor of FP results in FIT-based CRC screening programs.
Aged ; Colonoscopy ; Colorectal Neoplasms/*diagnosis ; Confidence Intervals ; Early Detection of Cancer/methods ; False Positive Reactions ; Female ; *Hemorrhoids ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; *Occult Blood ; Odds Ratio ; Regression Analysis ; Republic of Korea ; Retrospective Studies ; Unnecessary Procedures

PURPOSE: Limited data are available regarding the association between circulating serum carcinoembryonic antigen (CEA) or carbohydrate antigen 19-9 (CA 19-9) concentrations and colorectal adenoma. We aimed to investigate whether elevated serum CEA and CA 19-9 levels are correlated with the presence of colorectal neoplasia (CRN) and whether the levels of these antigens vary according to CRN severity. MATERIALS AND METHODS: A cross-sectional study was performed on asymptomatic subjects who underwent colonoscopy between 2010 and 2014 as part of a comprehensive health screening program in Korea. RESULTS: A total of 124509 participants with measured serum CEA levels and 115833 participants with measured serum CA 19-9 levels were analyzed. Elevated CEA concentrations were associated with a higher rate of any adenoma, advanced adenoma, high-risk adenoma, advanced CRN (ACRN), overall CRN, and colorectal cancer (CRC). Elevated CA 19-9 concentrations were also associated with a higher rate of advanced adenoma, high-risk adenoma, ACRN, and CRC. Both elevated levels of CEA and CA 19-9 were identified as independent predictors of ACRN. Among patients with CRN, the proportions of elevated CEA/CA 19-9 levels were significantly higher in patients with ACRN than in those with non-ACRN, and these levels were correlated with larger lesion size and multiplicity of adenomas. CONCLUSION: Both elevated serum CEA and CA 19-9 levels were associated with the presence of ACRN, as well as CRC. Elevated CEA levels were also associated with the presence of overall CRN. Moreover, both CEA and CA 19-9 levels were correlated with the severity of CRN.
Adenoma ; Carcinoembryonic Antigen ; Colonoscopy ; Colorectal Neoplasms ; Cross-Sectional Studies ; Humans ; Korea ; Mass Screening

PURPOSE: A substantial proportion of patients with colorectal cancer (CRC) present with iron deficiency anemia (IDA), and fecal immunochemical test (FIT) has proven to be an effective method for detecting the majority of CRC cases. A combination strategy of FIT results and IDA may be useful for risk stratification for detecting advanced colorectal neoplasia (ACRN). We compared the prevalence of ACRN among four groups stratified by FIT results and the presence of IDA. MATERIALS AND METHODS: A cross-sectional study was performed on asymptomatic male participants who underwent both FIT and colonoscopy between 2010 and 2014 as part of a comprehensive health screening program in Korea. RESULTS: Of 17236 participants, 522 (3.0%) showed positive FIT results and 26 (0.2%) had IDA. The mean age of the study participants was 40.8 years. The participants were classified into four groups: positive FIT result/IDA (G1, n=7), positive FIT result/no IDA (G2, n=515), negative FIT result/IDA (G3, n=19), and negative FIT result/no IDA (G4, n=16695). The prevalences of ACRN in G1, G2, G3, and G4 were 28.6, 13.4, 5.3, and 1.5%, respectively (p<0.001) and those of CRC were 28.6, 1.6, 0.0, and 0.01%, respectively (p<0.001). Subjects with positive FIT results and IDA had an increased risk of ACRN and CRC in both group aged <50 and ≥50 years. CONCLUSION: Subjects with positive FIT results and IDA had an increased risk of ACRN. Our results suggest that a combination strategy of FIT and IDA may be helpful in selecting and prioritizing asymptomatic men for colonoscopy.
Anemia, Iron-Deficiency* ; Colonoscopy ; Colorectal Neoplasms ; Cross-Sectional Studies ; Humans ; Iron* ; Korea ; Male ; Mass Screening ; Methods ; Prevalence

PURPOSE: Limited data are available regarding the associations between parameters of glucose and lipid metabolism and the occurrence of metachronous adenomas. We investigated whether these parameters affect the occurrence of adenomas detected on surveillance colonoscopy. MATERIALS AND METHODS: This longitudinal study was performed on 5289 subjects who underwent follow-up colonoscopy between 2012 and 2013 among 62171 asymptomatic subjects who underwent an initial colonoscopy for a health check-up between 2010 and 2011. The risk of adenoma occurrence was assessed using Cox proportional hazards modeling. RESULTS: The mean interval between the initial and follow-up colonoscopy was 2.2±0.6 years. The occurrence of adenomas detected by the follow-up colonoscopy increased linearly with the increasing quartiles of fasting glucose, hemoglobin A1c (HbA1c), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), and triglycerides measured at the initial colonoscopy. These associations persisted after adjusting for confounding factors. The adjusted hazard ratios for adenoma occurrence comparing the fourth with the first quartiles of fasting glucose, HbA1c, insulin, HOMA-IR, and triglycerides were 1.50 [95% confidence interval (CI), 1.26–1.77; p(trend)<0.001], 1.22 (95% CI, 1.04–1.43; p(trend)=0.024), 1.22 (95% CI, 1.02–1.46; p(trend)=0.046), 1.36 (95% CI, 1.14–1.63; p(trend)=0.004), and 1.19 (95% CI, 0.99–1.42; p(trend)=0.041), respectively. In addition, increasing quartiles of low-density lipoprotein-cholesterol and apolipoprotein B were associated with an increasing occurrence of adenomas. CONCLUSION: The levels of parameters of glucose and lipid metabolism were significantly associated with the occurrence of adenomas detected on surveillance colonoscopy. Improving the parameters of glucose and lipid metabolism through lifestyle changes or medications may be helpful in preventing metachronous adenomas.
Adenoma* ; Apolipoproteins ; Colonoscopy* ; Dyslipidemias ; Fasting ; Follow-Up Studies ; Glucose* ; Homeostasis ; Insulin ; Insulin Resistance ; Life Style ; Lipid Metabolism* ; Longitudinal Studies ; Proportional Hazards Models ; Triglycerides

BACKGROUND/AIMS: There has been no evidence for the necessity of endoscopy in asymptomatic young men with iron deficiency anemia (IDA). To determine whether endoscopy should be recommended in asymptomatic young men with IDA, we compared the prevalence of gastrointestinal (GI) lesions between young men (< 50 years) with IDA and those without IDA. METHODS: We conducted a case-control study on asymptomatic young men aged < 50 years who underwent both esophagogastroduodenoscopy (EGD) and colonoscopy as part of a health checkup between 2010 and 2014. RESULTS: Of 77,864 participants, 128 (0.16%) had IDA and 512 subjects without IDA were matched for several variables including age. Young men with IDA had a significantly higher proportion of colorectal cancer (CRC) (0.8% vs. 0.0%, p = 0.045), villous adenoma (0.8% vs. 0.0%, p = 0.045), and inflammatory bowel disease (IBD; 2.3% vs. 0.4%, p = 0.025) than those without IDA. Additionally, the prevalence of advanced colorectal neoplasia (ACRN) tended to be higher in subjects with IDA than in those without IDA (3.1% vs. 1.0%, p = 0.084). The prevalence of significant lower GI lesions including ACRN and IBD was higher in subjects with IDA than in those without IDA (5.5% vs. 1.4%, p = 0.011). Regarding upper GI lesions, a positive association with IDA was observed only for gastric ulcer (4.7% vs. 1.0%, p = 0.011). CONCLUSIONS: GI lesions including CRC, villous adenoma, IBD, and gastric ulcer were more common in asymptomatic young men with IDA. Our results suggest that EGD and particularly colonoscopy should be recommended even in asymptomatic young men with IDA.
Adenoma, Villous ; Anemia, Iron-Deficiency* ; Case-Control Studies ; Colonoscopy ; Colorectal Neoplasms ; Duodenoscopy ; Endoscopy* ; Endoscopy, Digestive System ; Humans ; Inflammatory Bowel Diseases ; Iron* ; Male ; Prevalence ; Stomach Ulcer

BACKGROUND/AIMS: Limited data are available regarding the association between age at menarche and the risk of colorectal adenoma. Therefore, we aimed to evaluate the relationship between reproductive factors including age at menarche and the risk of colorectal adenoma. METHODS: A cross-sectional study was performed on asymptomatic female subjects who underwent colonoscopy between 2010 and 2014 as part of a comprehensive health screening program in Korea. The association between reproductive factors including age at menarche and the presence of adenomas was assessed using multivariate logistic regression analysis. RESULTS: Among 32,620 asymptomatic female subjects, the proportion of patients with menarche at 10 to 11, 12 to 13, 14 to 15, 16 to 17, and 18 to 19 years of age was 4.1%, 31.7%, 45.4%, 14.9%, and 4.0%, respectively. Age at menarche was not significantly associated with the risk of any adenoma (adjusted odds ratio [AOR], 0.99; 95% confidence interval [CI], 0.97 to 1.02; p = 0.500) or advanced adenoma (AOR, 0.98; 95% CI, 0.91 to 1.04; p = 0.468) after adjusting for confounding factors. Age at menarche was not significantly associated with the risk of adenoma even among similar age groups. In addition, parity, use of female hormones, and menopause were not associated with the risk of adenoma. CONCLUSIONS Age at menarche, parity, use of female hormones, and menopause were not significantly associated with the risk of colorectal adenoma. Our findings indicate that reproductive factors including age at menarche do not affect the development of colorectal adenoma.