Diagnosis Of Colorectal Lesions Research Articles

Linked color imaging versus white light imaging in the diagnosis of colorectal lesions: a meta-analysis of randomized controlled trials.

Miss rate of colorectal neoplasia is associated with lesion histology, size, morphology, or location. We aim to compare the efficacy of Linked color imaging (LCI) versus white light imaging (WLI) for adenoma detection rate (ADR), the detection of sessile serrated lesions (SSLs), serrated lesions (SLs), advanced adenomas (AAs), diminutive lesions (DLs), and flat lesions (FLs) by using per-patient and per-lesion analysis based on randomized controlled trials (RCTs). Systematic review and meta-analysis. PubMed, Embase, and Cochrane databases were searched through May 1st, 2023. We calculated risk ratio for dichotomous outcomes and mean difference for continuous outcomes, and performed sensitivity analyses and subgroup analyses. Overall, 17 RCTs (10,624 patients) were included. In per-patient analysis, ADR was higher in the LCI group versus the WLI group (p < 0.00001). This effect was consistent for SSL (p = 0.005), SLs (p = 0.01), AAs (p = 0.04), DLs (p < 0.00001), and FLs (p < 0.0001). In per-lesion analysis, LCI showed a significant superiority over WLI with regard to the mean number of adenomas per patient (p < 0.00001). This effect was in accordance with mean SSL (p = 0.001), mean SLs (p < 0.00001), and mean DLs (p < 0.0001) per patient. A subgroup analysis showed that the beneficial effect of the LCI group on the detection of AAs, SSL, and FLs was maintained only for studies when experts and trainees were included but not for experts only. Meta-analyses of RCTs data support the use of LCI in clinical practice, especially for trainees.

Clinical value of JNET classification for non-real-time diagnosis of colorectal lesions

Objective To study the diagnostic value of Japan narrow band imaging expert team (JNET) classification for differentiating pathological type of colorectal lesions. Methods A total of 418 colorectal lesions were retrospectively diagnosed by magnifying endoscopy with narrow band imaging (ME-NBI) using JNET classification by two inexperienced doctors after a short time of training in JNET classification. Then lesions were diagnosed with Sano classification by the two doctors. Diagnostic results were compared with histologic findings as a golden standard. Results The sensitivity, specificity, and accuracy of JNET classification and Sano classification for neoplastic lesion differentiation were 98.2% VS 98.5%, 77.8% VS 66.7%, and 96.9% VS 96.4%, respectively (all P>0.05). These indicators for diagnosing cancerous lesions, including high grade intraepithelial neoplasia, intramucosal carcinoma and submucosal carcinoma, were 66.7% VS 80.2% (P=0.023), 87.6% VS 79.5% (P=0.006), and 82.1% VS 79.7% (P=0.379), respectively, and those for predicting submucosal deep invasive cancers were 34.8% VS 39.1%, 100.0% VS 99.0%, and 96.4% VS 96.3%, respectively (all P>0.05). The diagnostic accuracy of JNET classification for differentiating neoplastic lesions were 95.2% in those with diameter <10 mm, 97.0% in 10~<20 mm, and 97.8% in ≥20 mm (P=0.483), this finding were 95.2%, 85.1% and 72.1% for cancer, respectively (P<0.000 1), and 100%, 96.3%, and 94.4% for submucosal deep invasive cancer, respectively (P=0.026). Shape and location of colorectal lesions showed no significant effect on the diagnostic efficacy of JNET classification. Conclusion JNET classification is valuable for doctors without experience of ME-NBI in diagnosing colorectal lesions and the efficiency is slightly superior to Sano classification. However, the accuracy of diagnosis for cancer with diameter ≥20 mm need to be improved. Key words: Intestinal polyp; Diagnostic techniques, digestive system; Diagnostic imaging; JNET classification

Mo1985 Endocytoscopic Vascular Patterns Provide Highly Accurate Diagnosis of Colorectal Lesions

Mo1985 Endocytoscopic Vascular Patterns Provide Highly Accurate Diagnosis of Colorectal Lesions

Sa1591 The Diagnostic Ability of Micro Vascular Pattern Observed by Endocytoscopy

Sa1591 The Diagnostic Ability of Micro Vascular Pattern Observed by Endocytoscopy

705 Prophylasix of Post-ERCP Pancreatitis With Nafamostat Mesilate: Comparison of 24-Hour and 8-Hour Infusion of Nafamostat Mesilate: a Prospective Randomized Comparison Trial

705 Prophylasix of Post-ERCP Pancreatitis With Nafamostat Mesilate: Comparison of 24-Hour and 8-Hour Infusion of Nafamostat Mesilate: a Prospective Randomized Comparison Trial

Mo1646 Texture Analysis of Confocal LASER Endomicroscopy Images Using a Model of Gray Level Co-Occurrence Matrices

Confocal laser endomicroscopy (CLE) has shown high accuracy in the diagnosis of colorectal lesions by providing in vivo optical biopsies. It can differentiate between normal mucosa, neoplastic and inflammatory lesions based on the examiner's interpretation of crypts architecture and vascular pattern during ongoing colonoscopy. Texture analysis is used to find the texture boundaries, for the purpose of image segmentation. It can be helpful when objects in an image are more characterized by their texture than by intensity, such as the case of images obtained by CLE.

Digital Chromoendoscopy for Diagnosis of Diminutive Colorectal Lesions

Introduction. To compare the accuracy of digital and real-time chromoendoscopy for the differential diagnosis of diminutive (<5 mm) neoplastic and nonneoplastic colorectal lesions. Materials and Methods. This is a prospective randomized study comparing the Fujinon intelligent color enhancement (FICE) system (65 patients/95 lesions) and indigo carmine (69 patients/120 lesions) in the analysis of capillary meshwork and pit pattern, respectively. All lesions were less than 5 mm in diameter, and magnification was used in both groups. Histopathology was the gold standard examination. Results. Of 215 colorectal lesions, 153 (71.2%) were adenomas, and 62 were hyperplastic polyps (28.8%). Morphological analysis revealed 132 (61.4%) superficial lesions, with 7 (3.3%) depressed lesions, and 83 (38.6%) protruding lesions. Vascular meshwork analysis using FICE and magnification resulted in 91.7% sensitivity, 95.7% specificity, and 92.6% accuracy in differentiating neoplastic from nonneoplastic lesions. Pit pattern analysis with indigo carmine and magnification showed 96.5% sensitivity, 88.2% specificity, and 94.2% accuracy for the same purpose. Conclusion. Both magnifying virtual chromoendoscopy and indigo carmine chromoendoscopy showed high accuracy in the histopathological diagnosis of colorectal lesions less than 5 mm in diameter.

Tu1658 The Diagnosis of Colorectal Cancer With NBI Magnifying Endoscopy, Magnifying Chromoendoscopy and Endocytoscopy

The Diagnosis of Colorectal Cancer With NBI Magnifying Endoscopy, Magnifying Chromoendoscopy and Endocytoscopy Shin-Ei Kudo, Yoshiki Wada, Tomoyuki Ishigaki, Masashi Misawa, Yuichi Mori, Kunihiko Wakamura, Hideyuki Miyachi, Nobunao Ikehara, Fuyuhiko Yamamura, Shigeharu Hamatani Digestive Disease Center, Showa University Northern Yokohama Hospital, Yokohama, Japan; Department of Pathology, Showa University Northern Yokohama Hospital, Yokohama, Japan Aim: The aim of this prospective study is to compare the usefulness of magnifying narrow band imaging (NBI), magnifying chromoendoscopy and endocytoscopy for the diagnosis of colorectal lesions and providing precise treatment decision by means of a thorough NBI evaluation combined to pit pattern. Method: The subject sample was composed of 278 patients who underwent a complete colonoscopic examination and endoscopic or surgical treatment from January 2006 to June 2010. A total of 290 submucosal invasive cancerous lesions was evaluated. The NBI/chromoendoscopy digital images were recorded and the diagnosis was made independently from each other by two endoscopists who were blinded to the final pathological conclusion. The vascular pattern was classified into six classes accordingly to our service1. The pit pattern was classified according to Kudo’s classification. The findings of endocytoscopy were classified into five classes2. In submucosal cancers, 145 cases were treated surgically. What so ever Kudo’s classification was used for the degree of submucosal invasion and classified cancer accordingly. Prediction of the invasion depth is very important for deciding a way of intervention. Sm1a or 1b cancer without vessel permeation does not metastasize. In contrast, sm1c, sm2 or sm3 lesions show a substantial proportion (around 10%) of nodal metastasis. Massively invasive submucosal cancer (SMm) was indicated for surgical operation. Slightly invasive submucosal cancer (SMs) was indicated for endoscopic treatment. Results: By recognizing irregular or sparse vascular pattern with NBI, SMm could be diagnosed with sensitivity and specificity of 94.9% and 76.0% respectively. Through chromoendoscopy, the differentiation between SMm and SMs was achieved by evaluating the pit pattern with sensitivity of 89.7% and specificity of 88.0%. On the other hand, when assuming EC3b endocytoscopical class as SMm, SMm could be diagnosed with sensitivity and specificity of 89.9% and 90.0% respectively. Conclusion: In diagnosis of submucosal cancer, the specificity of pit pattern was superior to NBI colonoscopy. Thus, it is desirable to perform chromoendoscopy in addition to NBI for distinguishing between SMs and SMm lesions and determining treatment selection, whether endoscopical or surgically. Nevertheless, since a high accurate method, endocytoscopy might prove the best treatment selection in the future.1. Wada Y, Kudo S, Kashida H et al. The diagnosis of colorectal lesions with magnifying narrow-band imaging system. Gastrointest Endosc 2009; 70: 522-312. Kudo S, Takemura O, Ohtsuka K. Flat and Depressed Types of Early Colorectal Cancers: From East to West. Gastrointest Endoscopy Clin N Am 2008; 18: 581-593.

Serum M2-pyruvate kinase: A promising non-invasive biomarker for colorectal cancer mass screening

To explore the value of serum M2-pyruvate kinase (M2-PK) in colorectal cancer (CRC) mass screening. We conducted a molecular epidemiology study in Hangzhou, China, from year 2006 to year 2008. Serum samples were collected from 93 CRC, 41 advanced adenomas, 137 adenomas, 47 non-adenomatous polyps, and 158 normal participants in a community setting. Serum M2-PK and carcinoembryonic antigen (CEA) were measured using Enzyme-linked immunosorbent assay. SPSS 16.0 software was used to perform data analysis. Area under the receiver operating characteristic curve (AUC), sensitivity, and specificities were estimated for serum M2-PK in diagnosis of colorectal lesions and compared with CEA. Average serum M2-PK value among 158 normal people was 2.96 U/mL and not affected by gender (P = 0.47) or age (P = 0.59). Average serum M2-PK (U/mL) was 14.75 among stage III and 13.10 among stage I and II CRC patients, about 4 times higher than that among normal people. Average serum M2-PK was 8.58, 6.70, 5.13 and 2.51 U/mL among advanced adenoma, adenomas, non-adenomatous polyps, and inflammatory bowel disease patients, respectively. AUC for serum M2-PK was greater than that for CEA among all colorectal lesions. AUC for serum M2-PK was 0.89 (0.84, 0.94) (95% confidence interval), higher than that for CEA [0.70 (0.62-0.79)] in CRC stage I and II, 0.89 (0.84-0.94) vs 0.73 (0.63-0.83) in CRC stage III, 0.81 (0.74-0.86) vs 0.63 (0.53 - 0.73) in advanced adenomas, 0.69 (0.64-0.76) vs 0.54 (0.47-0.60) in adenomas, and 0.69 (0.62-0.78) vs 0.58 (0.48-0.68) in non-adenomatous polyps. The diagnostic sensitivity for all colorectal lesions increased with decrease in the cut-off value of serum M2-PK. The diagnostic sensitivity (%) of serum M2-PK was 100.00 for CRC, 95.12 advanced adenoma, 82.48 adenoma, and 82.98 non-adenomatous polyp. There were no CRC cases missed and 40.51% of unnecessary colonoscopies were avoided when the cut-off value was 2.00 U/mL. Serum M2-PK can be used as a primary screening test in CRC mass screening. It may be a promising non-invasive biomarker for CRC early detection.

Frequent somatic mutations of mitochondrial DNA in traditional serrated adenomas but not in sessile serrated adenomas of the colorectum

Serrated adenomas (SAs), recently subdivided into traditional SAs (TSAs) and sessile SAs (SSAs), are recognized as a distinct form of neoplasia of the colorectum. One of the characteristics of SAs is hypermaturation of the gland epithelium due to the low extent of cell loss by apoptosis. Mutations of mitochondrial DNA (mtDNA) are closely associated with abnormality in apoptosis. We therefore examined mtDNA mutations in colorectal lesions including hyperplastic polyps (HPs), SSAs, TSAs, and carcinomas. Examined were 25 HPs, 32 SSAs, 19 TSAs, and 138 carcinomas. The D310 region of the mtDNAs was examined by microsatellite assay. mtDNA mutations were detected in none of 25 (0%) HPs, one of 32 (3%) SSAs, six of 19 (32%) TSAs, and eleven of 133 (8%) carcinomas (five of the 138 carcinomas were not informative). The frequency of mtDNA mutations in the TSAs was significantly higher than that in the HPs, SSAs, and carcinomas (P = 0.004, P = 0.008, and P = 0.009, respectively). The frequency of mtDNA mutations in carcinomas was not significantly higher than that in HPs and SSAs (P = 0.14 and P = 0.28, respectively). Our data suggest that mtDNA mutations may play an important role in the development of TSAs and could be used as a genetic marker to aid in the diagnosis of colorectal lesions.

Diagnosis of colorectal lesions with a novel endocytoscopic classification – a pilot study

Recent advances in endocytoscopy have enabled in vivo evaluation not on ly of structural atypia, but also of cellular atypia with observation of lumens and nuclei in the surface layer of the mucosa. The aim of this prospective pilot study was to evaluate the usefulness of our novel endocytoscopic classification in colorectal lesions. A total of 206 consecutive patients were enrolled in the study and underwent endocytoscopic examination. Endocytoscopic images were stored electronically and two endoscopists blinded to the findings at live examination assigned them diagnoses using the endocytoscopic (EC) classification. The endocytoscopic diagnosis was then compared to the final histopathological diagnosis. In all, 196 patients with 213 specimens were available for analysis. All normal mucosae were classified as EC1a and all hyperplastic polyps as EC1b. Dysplasias were mainly classified as EC2, while massively invasive submucosal cancers (SMm) or worse, which have the possibility of metastasis, were mainly EC3b. Assuming that an EC1b classification was diagnostic of hyperplastic polyps, we were able to differentiate nonneoplastic from neoplastic lesions with a sensitivity of 100 % and a specificity of 100 % (P < 0.05). Assuming that an EC3b classification was diagnostic of SMm or worse, we were able to differentiate "SMm or worse" from other neoplastic lesions (dysplasias and slightly invasive submucosal cancers) with a sensitivity of 90.1 % and a specificity of 99.2 % (P < 0.05). The endocytoscopic classification was particularly useful for differentiating between neoplastic and nonneoplastic lesions and between "SMm or worse" and other neoplastic lesions, which in the case of colorectal neoplasms would help to determine treatment.

COMPARATIVE EVALUATION OF ENDOSCOPIC FACTORS FROM CONVENTIONAL COLONOSCOPY AND NARROW‐BAND IMAGING OF COLORECTAL LESIONS

Narrow-band imaging (NBI) diagnosis of colorectal lesions requires further consideration and standardized classification for attaining consensus among endoscopists. Compare vascular findings and diagnosis of colorectal lesions using various endoscopic images to assess effectiveness of NBI with magnification. Three endoscopic factors (vascular findings; diagnosis from NBI with magnification images; and total diagnosis from all available colonoscopic images including white light endoscopy, chromoendoscopy, NBI with magnification and magnifying chromoendoscopy) for 15 colorectal lesions were evaluated by 12 expert colonoscopists (Group A), 36 endoscopists not expert in colonoscopy (Group B) and 55 individuals not medical doctors, but familiar with gastrointestinal endoscopy or other medical products (Group C). We calculated accuracy percentages for all three endoscopic factors based on responses from each group. Highest percentage for vascular finding, NBI with magnification diagnosis and total diagnosis for each lesion assumed to be opinion of each group. We compared incidence of agreement among three groups and calculated invasion depth diagnostic accuracy rate for each group. For vascular findings from NBI with magnification images, incidence of complete agreement among three groups was 46.7%, incidence of disagreement among three groups was 46.7% and incidence of complete disagreement among three groups was 6.7%. For diagnosis from NBI with magnification images and total diagnosis from all available endoscopic images, incidence of complete agreement, disagreement and complete disagreement were 40.0%, 60.0% and 0.0%, respectively, and 60.0%, 40.0% and 0.0%, respectively. Invasion depth diagnostic accuracy from NBI with magnification images and all available endoscopic images were 60.0% and 73.3%, respectively, in Group A; 46.7% and 66.7%, respectively, in Group B; and 46.6% and 60.0%, respectively, in Group C. Results suggest some level of educational training is required for effective application of NBI with magnification for precise diagnosis of colorectal lesions.

CLINICAL USEFULNESS OF NARROW BAND IMAGING MAGNIFYING CLASSIFICATION FOR COLORECTAL TUMORS BASED ON BOTH SURFACE PATTERN AND MICROVESSEL FEATURES

We use the narrow band imaging (NBI) magnifying classification (Hiroshima Classification) on the basis of both their surface pattern and microvascular architecture to characterize colorectal tumors. Herein, we describe the Hiroshima Classification in detail and provide statistical data supporting its usefulness in diagnosing histologic type, whether a hyperplastic lesion, tubular adenoma, carcinoma with intramucosal to submucosal scanty invasion or carcinoma with submucosal massive invasion, and thus in selecting the appropriate treatment strategy. We also discuss the circumstances in which the Hiroshima Classification must be augmented by conventional pit pattern diagnosis. NBI magnification is easily carried out. We strongly recommend application of NBI magnification to the differential diagnosis of colorectal lesions as well as treatment decision making.

S1543: Simultaneous Evaluation of the Pit and Capillary Patterns of Colorectal Lesions on Routine Colonoscopy - Prime Time for Optical Biopsy

The endoscopic in vivo observation of microscopic superficial details of colorectal lesions is now possible. The differential diagnosis of small colorectal polyps and characterization of neoplastic lesions is crucial for a better screening colonoscopy and in choosing the right therapy for each colorectal lesion. Kudo et al. have proposed the pit pattern classification of colorectal lesions. Last year, we have developed an original endoscopic classification of the capillary pattern of colorectal lesions and reported its high accuracy rate in the diagnosis of colorectal lesions (GIE 2009).

S1571: Magnifying Endoscopy With Narrow-Band Imaging for Diagnosis of Colorectal Lesions

S1571: Magnifying Endoscopy With Narrow-Band Imaging for Diagnosis of Colorectal Lesions

Narrow-band imaging endoscopy in differential diagnosis of colorectal proliferative lesions

Objective To evaluate the narrow-band imaging （NBI） in differential diagnosis of colorectal proliferative lesions. Methods Suspected lesions in colon were examined with white light and NBI colonoscopy, respectively. The ensitivity and specificity in diagnosing colorectal inflammatory hyperplasia, adenoma, early cancer and advanced cancer were compared between NBI and conventional colonoscopy with reference to pathology as gold standard. The pit patterns and the surface microvessels of the lesions were also determined and scored with NBI combined with magnifying endoscopy, and were compared with pathological diagnosis. Results （ 1 ） A total of 368 lesions were detected in 280 patients with conventional colonoscopy and NBI. The sensitivity and specificity of NBI in differential diagnosis of colorectal lesions were superior to those of conventional colonoscopy. （2） The pit patterns of colorectal inflammatory hyperplasia were mainly type Ⅰ and Ⅱ , while in adenomas were mainly type Ⅱ and Ⅲ （94. 2% ）. The pit patterns of early cancer were type Ⅲ （ 18.8% ）, Ⅳ （56. 3% ） and V （25.0%）, and those of advanced cancer were mainly typeⅤ （94. 0% ）. （ 3 ） The average scores of surface microvessels of colorectal inflammatory hyperplasia, adenoma, early cancer and advanced cancer were 1.35 ± 0. 72, 3.86 ± 1.07, 6. 52 ± 2.59 and 11.42 ± 3.59, respectively. Scores over 6. 5 was a strong indicator of malignant lesions. Conclusion NBI is superior to conventional eolonoseopy in differential diagnosis of colorectal lesions. Observing pit patterns and microves-sels of the lesion with combination of NBI and magnifying endoscopy is helpful in diagnosis. Key words: Colonscopy ; Narrow-band imaging; lntestimal Neoplasms ; Microvessel

Diagnosis of colorectal lesions with the magnifying narrow-band imaging system

Narrow-band imaging (NBI) emphasizes the surface microvasculature of the GI tract and may help in detecting small neoplasms. The aim of this study was to clarify the value of the NBI system in tissue characterization and differential diagnosis. A prospective study. Digestive Disease Center of Showa University Northern Yokohama Hospital. The subjects were 495 patients who, from January 2006 to June 2007, underwent a complete colonoscopic examination. A total of 617 lesions were evaluated in the 495 patients (33 hyperplastic polyps, 532 adenomas, 52 submucosally invasive [T1] cancers). Most hyperplastic polyps showed a faint pattern. The vascular patterns of adenomas were mainly the network pattern or the dense pattern. The major vascular patterns of cancers were the irregular pattern and the sparse pattern. The irregular pattern was characteristic for protruded or flat-elevated cancers, whereas the sparse pattern was unique for depressed cancers. When we assumed that the faint pattern was diagnostic for hyperplastic polyps, we could differentiate between neoplastic and non-neoplastic lesions with a sensitivity of 90.9% and a specificity of 97.1%. Likewise, irregular and sparse patterns were assumed to be indices of massively invasive submucosal cancer, the sensitivity was 100%, the specificity was 95.8%, and the accuracy rate was 96.1%. This study was performed at a single center. The NBI system was valuable for distinguishing between neoplastic and non-neoplastic lesions, as well as between cancers and adenomas. Vascular pattern analysis can also be a promising tool for determining treatment selection, either endoscopy or surgery.

Diagnostic Accuracy of Pit Pattern and Vascular Pattern in Colorectal Lesions

Aim: The aim of this prospective study is to compare the usefulness of magnifying narrow band imaging (NBI) and magnifying chromoendoscopy in the diagnosis of colorectal lesions. Method: The subjects were 1185 patients who underwent a complete colonoscopic examination and endoscopic or surgical treatment, from January 2006 to February 2008. A total of 1473 lesions were evaluated (53 hyperplastic polyps, 1317 adenomas, 103 submucosally invasive cancers). The digital files of narrow band images and chromoendoscopic images were diagnosed independently from each other by the endoscopists who were blinded to the final pathological diagnosis.

Numerical analysis of the autofluorescence intensity of neoplastic and non-neoplastic colorectal lesions by using a novel videoendoscopy system

Autofluorescence endoscopy (AFE) may improve detection and diagnosis of colorectal lesions. Recently, AFE based on a high-resolution video endoscope was developed. A novel high-resolution video AFE system was used to quantify autofluorescence of colorectal lesions to determine the characteristics of non-neoplastic and neoplastic lesions. Retrospective observational study. Single-center referral hospital. Ninety-seven patients with 103 colorectal lesions (22 non-neoplastic and 81 neoplastic lesions) who underwent AFE and were treated by using endoscopy or by surgery. Recorded digital AFE images were analyzed to quantify autofluorescence. The following autofluorescence indexes were calculated: the green/red (G/R) ratio for each lesion, the color-contrast index between each lesion, and the corresponding normal region. The G:R ratio, color-contrast index, and histopathologic characteristics for each colorectal lesion. The mean G/R ratio was significantly higher in non-neoplastic lesions (1.17 [95% CI, 1.10-1.24], n = 22) than in neoplastic lesions (0.65 [95% CI, 0.63-0.68], n = 81) (P < .001). Mean color-contrast indexes were significantly lower in non-neoplastic lesions (7.99 [95% CI, 6.40-9.58], n = 22) than neoplastic lesions (35.06 [95% CI, 32.79-37.33], n = 81; P < .001). With a cutoff value of 1.01 for the G/R ratio and 13.94 for color-contrast index, AFE had a sensitivity and specificity of 98.8% and 86.4% respectively, for G/R ratio, and 98.8% and 90.9%, respectively, for color contrast index, in differentiating neoplastic from non-neoplastic colorectal lesions. Retrospective design. The quantification of digital AFE images obtained from the novel high-resolution videoendoscopy system revealed that autofluorescence was significantly different between non-neoplastic and neoplastic lesions, and color tone in AFE may represent the histopathologic characteristics of the lesion.

The Diagnosis of Colorectal Lesions with Magnifying Narrow Band Imaging (NBI) System

The surface microvasculature of the gastrointestinal tract is visualized with narrow band imaging (NBI) system, and it is especially useful for the diagnosis of small esophageal cancer. The aim of this study is to clarify the usefulness of NBI system with magnification for differential diagnosis in the colorectum. The subjects were 617 lesions (33 hyperplastic polyps, 532 adenomas and 52 invasive cancers limited to submucosal layer) which were observed by magnifying scope with NBI and treated endoscopically or surgically from January 2006 to June 2007.