Risk of lymph node metastasis after endoscopic treatment for rectal NETs 10 mm or less.

PURPOSE: For rectal neuroendocrine tumors (NETs) ≤ 10 mm, endoscopic resection is a standard treatment. However, there is no consensus whether additional surgery should be performed for patients at risk of lymph node metastasis (LNM) after endoscopic resection. The purpose of this study was to analyze the results of endoscopic resection and additional surgery of rectal NETs, thereby clarify the characteristics of cases with LNM. METHODS: This study was a multicenter retrospective cohort study conducted at 12 Japanese institutions. A total of 132 NETs ≤ 10 mm were analyzed regarding various therapeutic results. A comparative analysis was performed by dividing the cases into two groups that underwent additional surgery or not. Furthermore, the relationship between tumor size and LNM was examined. RESULTS: The endoscopic treatments were 12 endoscopic mucosal resections (EMR), 58 endoscopic submucosal resections with ligation (ESMR-L), 29 precutting EMRs, and 33 endoscopic submucosal dissections (ESD). The R0 resection rates of EMR were 41.7%, and compared to this rate, other three treatments were 86.2% (p < 0.001), 86.2% (p = 0.005), and 97.0% (p < 0.001), respectively. There were 41 non-curative cases (31.1%), and 13 had undergone additional surgery. Then, LNM was observed in 4 of the 13 patients, with an overall rate of LNM of 3.0% (4/132). The rate of positive lymphatic invasion and the rate of LNM by tumor size ≤ 6 mm and 7-10 mm were 9.7 vs. 15.4% (p = 0.375) and 0 vs. 10.3% (p = 0.007). CONCLUSIONS: A multicenter study revealed the priority of each endoscopic resection and the low rate of LNM for rectal NETs ≤ 6 mm.

Fatal gastrointestinal bleeding due to IgA vasculitis complicated with tuberculous lymphadenitis: A case report and literature review.

We report a case of IgA vasculitis that developed during the treatment of tuberculosis. Patients with tuberculosis who are on antituberculosis treatment can be administered steroids for severe disease or complications.

The Efficacy and Safety of Elobixibat for the Elderly with Chronic Constipation: A Multicenter Retrospective Cohort Study.

MATERIALS AND METHODS: This was a multicenter retrospective cohort study. The subjects were patients aged ≥20 years treated for chronic constipation from May 2018 to November 2019 at 12 related institutions. Patients were divided into ≤74 years and ≥75 years old. Elobixibat at 10 mg/day was prescribed for two weeks. We then analyzed the discontinuation due to ineffectiveness, change of spontaneous bowel movements (SBM), stool consistency, the time until the first SBM, adverse events, and effect-related factors. RESULTS: There were 140 cases (61 males) evaluated, with an average age of 72.1 ± 13.6 years (≤74 years: 71 cases; ≥75 years: 69 cases). The discontinuation rate was 7.9%. The SBM (times/week) increased from 2.86 to 6.08 (p < 0.001). The overall SBM improvement rate was 74.0% (≤74 years: 78.2% vs. ≥75 years: 68.9%, p = 0.31; male: 75.0% vs. female: 73.3%, p = 0.78). The overall improvement rate of stool consistency was 59.6% (≤74 years: 62.9%, ≥75 years: 56.1%, p = 0.42). The time until the first SBM (hours) for those ≤74 years and ≥75 years was 17.2 ± 14.3 and 11.2 ± 8.4 (p = 0.04). Adverse event rates for those ≤74 years and ≥75 years were 28.2% and 10.1% (p < 0.01). There were no significant effect-related factors for gender, age, and use of laxatives. CONCLUSIONS: Short-period elobixibat is shown to be effective also for the elderly and male.

High incidence of metachronous advanced adenoma and cancer after endoscopic resection of colon polyps ≥20 mm in size.

BACKGROUND AND AIM: There are limited studies on incidence rates of metachronous neoplastic lesions after resecting large colorectal polyps. In the present study, we analyzed metachronous lesions after endoscopic resection of colorectal polyps ≥20 mm in size. METHODS: We retrospectively analyzed consecutive patients who underwent endoscopic resection of polyps from 2006 to 2013 at two affiliated hospitals. All patients underwent at least two total colonoscopies before follow up to ensure minimal missed polyps. Only patients who had follow-up colonoscopy annually after resection were recruited. We separated patients according to size of polyp resected; there were 239 patients in the ≥20-mm group and 330 patients in the <20-mm group. Clinical characteristics and cumulative rates of metachronous advanced adenoma and cancer in both groups were analyzed. Advanced adenoma was defined as a neoplastic lesion ≥10 mm in size and adenoma with a villous component. RESULTS: Cumulative rate of development of metachronous advanced adenoma and cancer in the ≥20-mm group was significantly higher than in the <20-mm group (22.9% vs. 9.5%, P < 0.001) at 36 months. There was also more development of small polyps 5-9 mm in the ≥20-mm group than in the <20-mm group (45.2% vs. 28.8%, P < 0.001). With respect to metachronous lesions, there were more right-sided colonic lesions in the ≥20-mm group than in the <20-mm group (78.8% vs. 50.0%, P = 0.015). CONCLUSION: High incidence rates of development of metachronous neoplastic lesions were detected after resection of colorectal polyps ≥20 mm in size.

Ability of a novel blue laser imaging system for the diagnosis of colorectal polyps.

BACKGROUND: A new endoscope system with a laser light source, blue laser imaging (BLI), has been developed by Fujifilm that allows for narrow-band light observation. The aim of the present study was to evaluate the utility of BLI for the diagnosis of colorectal polyps. METHODS: We retrospectively analyzed 314 colorectal polyps that were examined with BLI observation at Kyoto Prefectural University of Medicine between September 2011 and January 2013. The surface and vascular patterns of polyps detected by published narrow-band imaging magnification: Hiroshima classification were used. Correlations were determined between the classifications and the histopathological diagnoses. Additionally, the ability of BLI without magnification to differentiate between neoplastic or non-neoplastic polyps was analyzed. RESULTS: A total of 41 hyperplastic polyps, 168 adenomas, 80 intramucosal cancer, 11 shallowly invaded submucosal cancer, and 14 deeply invaded submucosal cancer were analyzed.Hyperplastic polyp was observed in 100% of Type A lesions (39 lesions), adenoma was observed in 89.3% of Type B lesions (159 lesions), intramucosal cancer and shallowly invaded submucosal cancer was observed in 69.6% of Type C1 (92 lesions) and in 84.6% of Type C2 (13 lesions), and deeply invaded submucosal cancer was observed in 81.8% of Type C3 lesions (11 lesions). The overall diagnostic accuracy of BLI with magnification was 84.3%. Additionally, the diagnostic accuracy of BLI without magnification for differentiating between neoplastic and non-neoplastic polyps <10 mm in diameter was 95.2%, which was greater than that of white light (83.2%). CONCLUSION: BLI was useful for the diagnosis of colorectal polyps.

The ability of a novel blue laser imaging system for the diagnosis of invasion depth of colorectal neoplasms.

BACKGROUND: Fujifilm has developed a novel endoscope system with two kinds of lasers that enables us to allow narrow-band light observation with blue laser imaging (BLI). The aim of this study was to evaluate BLI magnification in comparison with narrow-band imaging (NBI) magnification for the diagnosis of colorectal neoplasms. METHODS: This was a multicenter open study. A total of 104 colorectal neoplasms were examined with BLI and NBI magnifications in Kyoto Prefectural University of Medicine and Fukuoka University Chikushi Hospital. Vascular and surface patterns of tumors under BLI magnification were compared with those under NBI magnification, using a published NBI classification. The main outcome was the correlation between the NBI classification diagnosed by BLI or NBI magnification and the histopathological analyses. RESULTS: Sixty-two cases of adenoma, 34 cases of intramucosal cancer and shallowly invaded submucosal cancer, and eight cases of deeply invaded submucosal cancer were diagnosed. The diagnostic accuracy of BLI magnification in the NBI classification was 74.0 % (77/104), similar to that of NBI magnification (77.8 %). The consistency rate between BLI and NBI magnification in the NBI classification was 74.0 %. Concerning image evaluation, the interobserver variability of two expert endoscopists (N.Y. and T.H.) in BLI magnification was κ = 0.863. On the other hand, the intraobserver variability of the two endoscopists was κ = 0.893 (N.Y.) and 0.851 (T.H.). CONCLUSIONS: BLI magnification by laser source could predict histopathological diagnosis and invasion depth of colorectal neoplasms. The diagnostic effectiveness of this method was similar to that of NBI magnification.

MDR1 is related to intestinal epithelial injury induced by acetylsalicylic acid.

BACKGROUND/AIMS: Although the cytotoxicity of aspirin against the intestinal epithelium is a major clinical problem, little is known about its pathogenesis. We assessed the involvement of Multi Drug Resistance (MDR) 1 in intestinal epithelial cell injury caused by aspirin using MDR1 gene-transfected Caco2 cells. METHODS: Caco2 cells were treated with various concentrations of aspirin for 24 h. After treatment of Caco2 cells with verapamil, a specific inhibitor of MDR1, we assessed the extent of cell injury using a WST-8 assay at 24 h after aspirin-stimulation. We performed the same procedure in MDR1 gene-transfected Caco2 cells. To determine the function of MDR1 in the metabolism of aspirin, flux study was performed using (14)C-labeled aspirin. RESULTS: The level of aspirin-induced cell injury was higher in verapamil-treated Caco2 cells than in control cells and was less serious in MDR1-transfected Caco2 cells than in control vector-transfected cells. The efflux of (14)C-labeled aspirin was higher in verapamil-treated Caco2 cells than in control cells. CONCLUSION: These data suggest that aspirin effux occurs through the MDR1 transporter and that the MDR1 transporter is involved in the pathogenesis of aspirin-induced cell injury.

Prediction and treatment of difficult cases in colorectal endoscopic submucosal dissection.

Purpose. The aim of this study was to examine the characteristics of difficult cases and the learning curve in colorectal endoscopic submucosal dissection (ESD). Methods. We studied 518 colorectal tumors treated by ESD. Patients were divided into 2 groups such as the difficult ESD group and non-difficult ESD group in view of procedure time and procedure speed, respectively. The clinical features in each group were analyzed, and we also examined cases with severe fibrosis. Furthermore, we divided all cases into 5 periods according to experience of ESDs and investigated the rates of difficult and perforation cases. Results. In view of both procedure time and procedure speed, there were significant differences about mean tumor size, rates of severe fibrosis and perforation, and en bloc resection rate between the two groups. Severe fibrosis was detected in protruding tumors >40 mm in diameter. With respect to the learning curve, the rate of difficult and perforation cases decreased significantly in the late periods compared to the first period. Conclusions. Large tumor size, high rates of severe fibrosis and perforation, and low rate of en bloc resection are related with difficult ESD cases. The increasing of experiences can decrease the rate of difficult cases and perforation.

Prevention and management of complications of and training for colorectal endoscopic submucosal dissection.

Endoscopic submucosal dissection (ESD) is reported to be an efficient treatment with a high rate of en bloc resection for large colorectal tumors in Japan and some other Western and Asian countries. ESD is considered less invasive than laparoscopic colectomy. However, ESD carries a higher risk of perforation than endoscopic mucosal resection (EMR). Various devices and training methods for colorectal ESD have been developed to solve the difficulties. In this review, we describe the complications of colorectal ESD and prevention of those complications. On the other hand, colorectal ESD is difficult for less-experienced endoscopists. The unique step-by-step ESD training system is performed in Japan. Additionally, appropriate training, including animal model training, for colorectal ESD should be acquired before working on clinical cases.

Role of metallothionein in murine experimental colitis.

Metallothioneins (MTs) are a family of cysteine-rich low molecular-weight proteins that can act as reactive oxygen species scavengers. Although it is known that the induction of MT expression suppresses various inflammatory disorders, the role of MTs in intestinal inflammation remains unclear. In this study, we investigated the effects of dextran sulfate sodium (DSS) administration in mice with targeted deletions of the MT-I/II genes. Acute colitis was induced by 2% DSS in male MT-I/II double knockout (MT-null) and C57BL/6 (wild-type) mice. The disease activity index (DAI) was determined on a daily basis for each animal, and consisted of a calculated score based on changes in body weight, stool consistency and intestinal bleeding. Histology, colon length, myeloperoxidase (MPO) activity and colonic mRNA expression and the concentration of inflammatory cytokines were evaluated by real-time-PCR and enzyme-linked immunosorbent assay (ELISA). The localization of MTs and macrophages was determined by immunohistological and immunofluorescence staining. To investigate the role of MTs in macrophages, peritoneal macrophages were isolated and their responses to lipopolysaccharide were measured. Following DSS administration, the DAI score increased in a time-dependent manner and was significantly enhanced in the MT-I/II knockout mice. Colonic MPO activity levels and inflammatory cytokines [tumor necrosis factor (TNF)-α, interferon (IFN)-γ and interleukin (IL)-17] production increased following DSS administration, and these increases were significantly enhanced in the MT-I/II knockout mice compared with the wild-type mice. MT-positive cells were detected in the lamina propria and submucosal layer by immunohistochemical and immunofluorescence staining, and were mainly co-localized in F4/80-positive macrophages. The production of inflammatory cytokines (TNF-α, IFN-γ and IL-17) from isolated peritoneal macrophages increased following lipopolysaccharide stimulation, and these increases were significantly enhanced in the macrophages obtained from the MT-I/II knockout mice. These data indicate that MTs play an important role in the prevention of colonic mucosal inflammation in a mouse model of DSS-induced colitis, thus suggesting that endogenous MTs play a protective role against intestinal inflammation.

Multicenter study of endoscopic mucosal resection using 0.13% hyaluronic acid solution of colorectal polyps less than 20 mm in size.

PURPOSE: Endoscopic mucosal resection (EMR) of colorectal polyps should be curative and safe. This study aimed to determine the efficacy and safety of colorectal EMR using 0.13% hyaluronic acid (HA) solution. METHODS: This was a single-armed multicenter prospective open trial conducted at 11 Japanese institutions. Lesion characteristics and various measures of clinical outcome, including en bloc resection, histopathologically complete resection, and postoperative bleeding were analyzed for 624 consecutive patients who underwent EMR of colorectal polyps at ≤20 mm in size from August 2010 to September 2011. RESULTS: En bloc and complete resection were achieved in 93.3 and 78.3% of 624 lesions. The median EMR procedure time was 2.1 ± 1.5 min. The rates of postoperative bleeding and perforation were 1.1 and 0%. The rate of en bloc resection was higher for polyps at 5-10 mm than for polyps at 11-20 mm (95.1 vs. 85.1%; P < 0.001) and was higher for protruding polyps than for superficial polyps (94.5 vs. 87.1%; P < 0.05). The rate of en bloc resection was also higher for polyps in the left-side colon than for those in the right-side colon or rectum (96.7 vs. 91.6 vs. 90.8%; P < 0.05). Multivariate analysis showed that polyp at 11-20 mm in size and location not on the left-side colon was significantly independent risk factors for failure of en bloc resection. CONCLUSION: EMR using 0.13% HA of colorectal polyps less than 20 mm in size had high rates of en bloc and complete resection and few complications.

Hemin ameliorates indomethacin-induced small intestinal injury in mice through the induction of heme oxygenase-1.

BACKGROUND AND AIM: Although non-steroidal anti-inflammatory drugs can induce intestinal injury, the mechanisms are not fully understood, and treatment has yet to be established. Heme oxygenase-1 (HO-1) has recently gained attention for anti-inflammatory and cytoprotective effects. This study aimed to investigate the effects of hemin, an HO-1 inducer, on indomethacin-induced enteritis in mice. METHODS: Enteritis was induced by single subcutaneous administration of indomethacin (10 mg/kg) in male C57BL/6 mice. Hemin (30 mg/kg) was administered by intraperitoneal administration 6 h before indomethacin administration. Mice were randomly divided into four groups: (i) sham + vehicle; (ii) sham + hemin; (iii) indomethacin + vehicle; or (iv) indomethacin + hemin. Enteritis was evaluated by measuring ulcerative lesions. Myeloperoxidase activity was measured as an index of neutrophil accumulation. The mRNA expression of inflammatory cytokines and chemokines, such as tumor necrosis factor-α, monocyte chemoattractant protein-1, macrophage inflammatory protein-1α, and keratinocyte chemoattractant, were analyzed by real-time polymerase chain reaction. RESULTS: The area of ulcerative lesions, myeloperoxidase activity, and mRNA expression of inflammatory cytokines and chemokines were significantly increased in mice administrated with indomethacin compared with vehicle-treated sham mice. Development of intestinal lesions, increased levels of myeloperoxidase activities, and mRNA expressions of inflammatory cytokines and chemokines were significantly suppressed in mice treated with hemin compared with vehicle-treated mice. Protective effects of hemin were reversed by co-administration of tin protoporphyrin, an HO-1 inhibitor. CONCLUSIONS: Induction of HO-1 by hemin inhibits indomethacin-induced intestinal injury through upregulation of HO-1. Pharmacological induction of HO-1 may offer a novel therapeutic strategy to prevent indomethacin-induced small intestinal injury.

Possibility of ex vivo animal training model for colorectal endoscopic submucosal dissection.

PURPOSE: Colorectal endoscopic submucosal dissection (ESD) has not been standardized due to technical difficulties and requires extensive training for reliability. Ex vivo animal model is convenient, but has no blood flow. The objective of this study is to evaluate the characteristics of various ex vivo animal models including a blood flow model for colorectal ESD training and the usefulness of practicing endoscopic hemostasis and closure using an animal model. METHODS: Harvested porcine cecum, rectum, and stomach and bovine cecum and rectum were analyzed regarding ease of mucosal injection, degree of submucosal elevation, and status of the proper muscle layer. Ex vivo animal model with blood flow was made using the bovine cecum. The vessel around the cecum was detached, and red ink was injected. Endoscopic hemostasis for perioperative hemorrhage and endoscopic closure for perforation were performed in this model. RESULTS: Mucosal injection was easily performed in the bovine cecum and rectum. Submucosal elevation was low in the bovine cecum, while the proper muscle layer was not tight in the porcine rectum and bovine cecum. Endoscopic hemostasis were accomplished in six (60 %) out of ten procedures of the ex vivo blood flow model. In two non-experts, the completion rates of endoscopic closure were 40 and 60 % in the first five procedures. These rates became 100 % in the last five procedures. CONCLUSIONS: We have evaluated the characteristics of various ex vivo animal models and shown the possibility of training for endoscopic hemostasis and endoscopic closure in the ex vivo animal model.

Acetyl salicylic acid induces damage to intestinal epithelial cells by oxidation-related modifications of ZO-1.

Acetyl salicylic acid (ASA) is one of the most frequently prescribed medications for the secondary prevention of cardiovascular and cerebrovascular events. It has recently been reported to cause small intestinal mucosal injury at a considerably higher rate than previously believed. The aim of this study is to investigate the mechanism by which this occurs using an in vitro small intestine model focusing on the role of oxidative stress and cell permeability. Differentiated Caco-2 exhibits a phenotype similar to human small intestinal epithelium. We measured whether ASA induced the increase of differentiated Caco-2 permeability, the decrease of tight junction protein expression, the production of reactive oxygen species (ROS), and the expression of ROS-modified zonula occludens-1 (ZO-1) protein. In some experiments, Mn(III) tetrakis(1-methyl-4-pyridyl)porphyrin (MnTMPyP, a superoxide dismutase mimetic) was used. The nontoxic concentration of ASA decreased transepithelial electrical resistance and increased the flux of fluorescein isothiocyanate-conjugated dextran across Caco-2 in a time-dependent manner. The same concentration of ASA significantly decreased ZO-1 expression among TJ proteins as assessed by Western blot and immunocytochemistry and increased ROS production and the expression of oxidative stress-modified ZO-1 protein. However, MnTMPyP suppressed the ASA-induced increased intercellular permeability and the ASA-induced ROS-modified ZO-1 expression. Our findings indicate that ASA-induced ROS production can specifically modify the expression of ZO-1 protein and induce increased cell permeability, which may ultimately cause small intestinal mucosal injury.

Endoscopic mucosal resection with 0.13% hyaluronic acid solution for colorectal polyps less than 20 mm: a randomized controlled trial.

BACKGROUND AND AIM: Adequate mucosal elevation by submucosal injection is important for definitive en bloc resection and prevention of perforation during endoscopic mucosal resection (EMR). The objective of this study is to determine the efficacy of 0.13% hyaluronic acid (HA) solution for high and sustained mucosal elevation during colorectal EMR. METHODS: The study was a prospective randomized controlled trial; a total of 196 patients with colon polyps of < 20 mm diameter were enrolled and randomized in a 1:1 ratio to undergo EMR using either 0.13% HA or normal saline (NS). The primary outcome of the study was histopathologically confirmed complete resection. The secondary outcomes such as maintenance of high mucosal elevation and development of complications were also evaluated. Moreover, the relationship between complete resection and the experience of the endoscopist (veteran vs less experienced) was analyzed. RESULTS: Compete resection was achieved in 74 of 93 polyps (79.5%) in the 0.13% HA group and 63 of 96 polyps (65.6%) in the NS group (P < 0.05). High mucosal elevation was maintained in 83.9% of procedures in the 0.13% HA group and 54.1% in the NS group (P < 0.01). The frequency of complete resection achieved by less-experienced endoscopists was higher in the 0.13% HA group (79.3%) than in the NS group (62.1%; P < 0.05). CONCLUSIONS: Endoscopic mucosal resection using 0.13% HA to colon polyps of less than 20 mm diameter is more effective than NS for complete resection and maintenance of mucosal elevation.

The detection of surface patterns by flexible spectral imaging color enhancement without magnification for diagnosis of colorectal polyps.

PURPOSE: Flexible spectral imaging color enhancement (FICE), or image-enhanced endoscopy, can enhance visualization of surface and vascular patterns of colorectal polyps. Resolution of FICE has recently been improved. We evaluated diagnostic accuracy for neoplastic and non-neoplastic colorectal polyp differentiation with detection of surface patterns by FICE without magnification. METHODS: Retrospective analysis of 151 colorectal polyps evaluated by FICE without magnification was performed. Neoplastic surface patterns were defined as tubular and oval pit. We aimed to determine sensitivity, specificity, positive and negative predictive values (PPV and NPV), and accuracy in correlating diagnosis by FICE without magnification with histology. Moreover, findings were compared to those of white-light endoscopy (WL) and chromoendoscopy (CHR). RESULTS: Of the 151 colorectal polyps, 95 were identified as neoplastic and 56 were identified as non-neoplastic. FICE without magnification had a sensitivity of 89.4%, specificity of 89.2%, PPV of 93.4%, NPV of 83.3%, and accuracy of 89.4%. The accuracy of FICE value was higher than that of WL (sensitivity of 74.7%, specificity of 73.2%, PPV of 82.5%, NPV of 63.0%, and accuracy of 74.1%) and was worse than that of CHR (sensitivity of 96.8%, specificity of 89.2%, PPV of 93.9%, NPV of 96.1%, and accuracy of 94.7%). Imaging evaluation was validated by inter-/intra-observer measurements, demonstrating consistent results. CONCLUSIONS: The detection of surface patterns by FICE without magnification is useful for differential diagnosis of colorectal polyps. We believe that FICE without magnification is more convenient and easier method than CHR.

Efficacy of hyaluronic acid in endoscopic mucosal resection of colorectal tumors.

BACKGROUND AND AIM: Endoscopic mucosal resection (EMR) is the standard procedure for colorectal tumors. High mucosal elevation by submucosal injection is important for definite en bloc resection and the prevention of perforation. Hyaluronic acid (HA) is a reportedly useful injection solution for high and long-lasting mucosal elevation, but the ideal HA concentration for optimization of mucosal elevation maintenance, injection pressure, and cost is unknown. In the present study, we assessed the appropriate concentration of HA for EMR. METHODS: A resected porcine colon and esophagus were used. The injection solutions examined were 0.9% normal saline (NS) and four concentrations of an 800-KDa HA preparation (0.4%, 0.2%, 0.13%, and 0.1%). Each solution (2 mL) was injected into the submucosa; injection pressure was calculated, and elevation was measured. The durations of mucosal elevation and EMR were additionally assessed in the living minipig colon. RESULTS: In the resected porcine colon, the mucosal elevation was measured 0, 2, 4, and 6 min after the submucosal injection. All concentrations of HA solution maintained greater mucosal elevation at all times than NS (P < 0.05). An almost similar result was obtained in the resected porcine esophagus. The injection pressure correlated with the HA concentration. In the living minipig colon, mucosal elevation diminished 2 min after the submucosal injection with NS, but was maintained 2 min after injection with 0.4%, 0.2%, and 0.13% HA. The average duration of EMR was 139 s. CONCLUSIONS: Mucosal elevation by HA was greater than that by NS in resected and living animal models. We recommend 0.13% HA for maintaining mucosal elevation, injection pressure, and cost.

Efficacy of magnifying endoscopy with flexible spectral imaging color enhancement in the diagnosis of colorectal tumors.

BACKGROUND: Magnifying endoscopy with flexible spectral imaging color enhancement (FICE) is an image-enhanced endoscopy that captures the surface and vascular patterns of colorectal tumors. We evaluated and compared FICE magnification to narrow-band imaging (NBI) magnification. METHODS: Flexible spectral imaging color enhancement or NBI magnification was performed to the visualize surface and vascular patterns of colorectal tumors, classified into 4 types: Type A, Type B, Type C1/C2, and Type C3, as previously reported. A total of 235 colorectal tumors were examined. The correlations between classifications found by FICE or NBI magnification and histopathological diagnoses were examined. Image evaluation was validated by assessing inter-observer and intra-observer agreements on examinations. RESULTS: Twenty-eight hyperplastic polyps (HPs), 115 tubular adenomas (TAs), 72 mucosal and slightly invaded submucosal cancers (M-sSM), and 20 massively invaded submucosal cancers (mSM) were diagnosed. By FICE magnification, HP and TA were observed in 93.3 and 6.7% of Type A (15 lesions), respectively. TA, M-sSM, and HP were observed in 82.6, 15.4, and 2.0% of Type B (52 lesions),respectively. M-sSM, TA, and mSM were observed in 50.0,46.0, and 4.0% of Type C1/2 (50 lesions), respectively.mSMs were observed in all 7 Type C3 lesions. In diagnosing mSM in Type C3, the sensitivity and specificity of FICE magnification were 77.7 and 100%, respectively, compared to those of NBI, at 63.6 and 99.0%, respectively. Imaging evaluation was validated accurately by intra- and intraobserver measurements showing consistent results. CONCLUSIONS: The classification of colorectal tumors by FICE magnification correlated well with the histopathological diagnoses, similar to findings for NBI magnification. FICE magnification can be evaluated accurately with the same diagnostic classifications as those used for NBI magnification.

Efficient hemostatic method for endoscopic submucosal dissection of colorectal tumors.

AIM: To evaluate a new hemostatic method using hemostatic forceps to prevent perforation and perioperative hemorrhage during colonic endoscopic submucosal dissection (ESD). METHODS: We studied 250 cases, in which ESD for colorectal tumors was performed at the Kyoto Prefectural University of Medicine or Nara City Hospital between 2005 and 2010. We developed a new hemostatic method using hemostatic forceps in December 2008 for the efficient treatment of submucosal thick vessels. ESD was performed on 126 cases after adoption of the new method (the adopted group) and the new method was performed on 102 of these cases. ESD was performed on 124 cases before the adoption of the new method (the unadopted group). The details of the new method are as follows: firstly, a vessel was coagulated using the hemostatic forceps in the soft coagulation mode according to the standard procedure, and the coagulated vessel was removed using the forceps in the "endocut" mode without perioperative hemorrhage. Secondly, the partial surrounding submucosa was dissected using the forceps in the endocut mode. In the current study, we evaluated the efficacy of this method. RESULTS: Coagulated vessels were successfully removed using the hemostatic forceps in all 102 cases without severe perioperative hemorrhage. Moderate perioperative hemorrhage occurred in five cases (4.9%); however, it was stopped by immediately reuse of the hemostatic forceps. The partial surrounding submucosa was dissected using the forceps in all 102 cases. In the adopted group, the median operation time was 105 min. The proportion of endoscopic en bloc resection was 92.8% (P < 0.01) compared to 80.6% in the unadopted group. The postoperative hemorrhage and perforation rates were 2.3% and 2.3%. The rate of perforation was significantly lower than that in the unadopted group (9.6%, P < 0.01). We evaluated the ease of use of this method by allowing our three trainees to performed ESD on 46 cases, which were accomplished without any severe hemorrhage. CONCLUSION: The new method effectively treated submucosal thick vessels and shows promise for the prevention of perforation and perioperative hemorrhage in colonic ESD.

[A case of hypervascular hyperplastic nodule in chronic alcoholic liver disease with corona-like enhancement in the late phase image of CT during hepatic arteriography].

A 46-year-old woman was admitted to our hospital with hepatic encephalopathy due to alcoholic liver disease. A hepatic nodule (20 mm in diameter) in S7 was enhanced in the early phase of contrast CT. No significant findings were observed in the late phase of contrast CT and SPIO MRI. The late phase of CT during hepatic arteriography showed corona-like enhancement of the nodule. The nodule was diagnosed as a hypervascular hyperplastic nodule, based on histological examinations and immunohistochemical results with antibodies against CD68 and CD34.