Clinical usefulness of the hold-and-drag closure using the SB clip for large mucosal defects after colorectal endoscopic submucosal dissection

BACKGROUND

Endoscopic clip closure of mucosal defects after colorectal endoscopic submucosal dissection (ESD) reduces the risk of postoperative adverse events, but achieving complete closure for large mucosal defects can be difficult. The aim of this study was to evaluate the effectiveness of the hold-and-drag closure using an SB clip compared with that of the conventional closure for mucosal defects after colorectal ESD.

METHODS

Eighty-four consecutive colorectal lesions resected by ESD at the Hiroshima Asa Citizens Hospital were registered and randomly allocated to two groups (Group A: SB clip, Group B: EZ clip), and then endoscopic closures were performed. We crossed-over to the SB clip in situations where the initial closure using an EZ clip was unsuccessful in achieving complete closure. Outcomes were compared and analyzed.

RESULTS

Forty-two lesions were randomly assigned to groups A and B. The complete closure rate was significantly higher in group A, especially in resected specimens with a diameter of 30 mm or more. Twelve lesions that failed complete closure in group B were changed to SB clips, and 95% of the whole of group B were successfully closed. There were no significant differences in procedural time, number of clips, and cost of clips between groups A and B.

CONCLUSION

Compared with the conventional closure, the hold-and-drag closure using an SB clip is a more suitable method for complete closure, especially for large mucosal defects of 30 mm or more. Furthermore, this is a simpler and more economical compared to a zipper closure using EZ clips.

Optimal candidates for early colonoscopy in the management of acute lower gastrointestinal bleeding

BACKGROUND AND AIM

Early colonoscopy has not shown any advantages over elective colonoscopy in reducing the risk of early rebleeding (≤ 30 days) after acute lower gastrointestinal bleeding (ALGIB). Considering the heterogeneity among patients with ALGIB, we sought to evaluate appropriate candidates for early colonoscopy.

METHODS

A total of 592 patients with ALGIB were enrolled, and the clinical outcomes of early colonoscopy were investigated. Thereafter, the participants were divided into two groups: the recent bleeding group (n = 445), with hematochezia 0-6 h before hospital arrival, and non-recent bleeding group (n = 147). The clinical outcomes yielded by early colonoscopy were assessed in each group.

RESULTS

The multivariate analysis including the entire population revealed that early colonoscopy (< 24 h) did not reduce the risk of early rebleeding (adjusted odds ratio [AOR], 0.88; 95% confidence interval [CI], 0.55-1.39). However, in the subgroup analysis, early colonoscopy independently reduced the risk of early rebleeding in the recent bleeding group (AOR, 0.56; 95% CI, 0.33-0.94). Moreover, a reduction in the need for radiological or surgical intervention (AOR, 0.34), transfusion (AOR, 0.62), and prolonged hospitalization (AOR, 0.42), as well as improvement in diagnostic yield (AOR, 1.78) and endoscopic treatment rates (AOR, 1.66), were observed. Early colonoscopy did not improve the outcomes of the non-recent bleeding group.

CONCLUSIONS

Early colonoscopy is not required for all patients with ALGIB. However, it may be suitable for those with hematochezia 0-6 h before hospital arrival, as it reduces early rebleeding and improves clinical outcomes.

[Two rare cases of severe hyponatremia with consciousness disorder following bowel preparation and high fluid intake]

Symptomatic hyponatremia due to bowel preparation is extremely rare, but it can cause severe neurological symptoms and require hospitalization. We report our experience with two cases of symptomatic hyponatremia after bowel preparation. Our findings suggest that the cause of hyponatremia may be not only oral bowel cleansing agents but also high fluid intake. Adjusting the dose and pace of oral bowel cleansing agents and fluid intake;rehydration should be considered to prevent any recurrences.

Pyogenic Granuloma Mimicking T1 Colorectal Carcinoma

Pyogenic granuloma (PG), a benign capillary hemangioma, is extremely rare in the colon. Here, we present a case of PG that was difficult to distinguish from T1 (deep submucosal invasive) colorectal carcinoma. A 57-year-old woman with no remarkable history was referred to us for a detailed investigation of a positive fecal occult blood test. Colonoscopy revealed a reddish, irregular-shaped, protruding lesion (5 mm) in the rectum. We performed endoscopic mucosal resection of the lesion as total excisional biopsy because T1 colorectal carcinoma was suspected, despite the lesion’s small size after observation by magnifying endoscopy. Histologically, the protruding lesion mainly consisted of numerous capillaries lined with plump and flat endothelial cells without signs of malignancy. Colorectal carcinoma, on the other hand, is composed of tall columnar atypical epithelial cells showing neoplastic proliferation. Thus, cell morphology is completely different between PG and colorectal carcinoma. The final diagnosis was colonic PG with a negative vertical margin. In conclusion, physicians should be aware of a colorectal protruding lesion devoid of malignant potential, as in this case, where the lesion was difficult to diagnose accurately and to distinguish from T1 colorectal carcinoma on magnifying endoscopy. Physicians should consider PG as a differential diagnosis in similar cases.

A pilot study to evaluate the effectiveness and safety of urgent endoscopy for gastroduodenal perforation

BACKGROUND

Gastroduodenal perforation is potentially life threatening and requires early diagnosis and treatment. Urgent endoscopy facilitates detecting bleeding sites and achieving hemostasis. However, there is no consensus on urgent endoscopy for gastroduodenal perforation in Japan.

METHODS

We evaluated the effectiveness and safety of urgent endoscopy for gastroduodenal perforation. We compared clinical characteristics between 140 patients who underwent urgent endoscopy (urgent endoscopy group) and 16 patients did not (no urgent endoscopy group) at Hiroshima City Asa Citizens Hospital between December 2005 and December 2018.

RESULTS

Endoscopic diagnosis was possible in all urgent endoscopy group. In contrast, correct diagnosis of the perforation site was made on CT in 99 cases (63%). Furthermore, the proportion of cases with correct diagnosis of the perforation site by CT findings differed significantly between the urgent endoscopy group and the no urgent endoscopy group (66% vs. 38%, p < 0.05). No complications of urgent endoscopy were observed. Primary perforation site was gastric in 42 cases and duodenal in 114. In the 42 gastric perforation cases, 12 gastric perforation cases (29%) were managed conservatively, successfully in 9 (75%); 2 cases (17%) required delayed emergency surgery for worsening peritonitis. In the 114 duodenal perforation cases (duodenal ulcer in all cases), 52 cases (46%) were managed conservatively, successfully in 48 (92%); 3 cases (6%) required delayed emergency surgery for worsening peritonitis. A significantly higher proportion of gastric perforation cases than duodenal perforation cases required surgical treatment (76% vs. 57%, p < 0.05). Multivariate analysis revealed localized abdominal pain (no peritonism) (OR 0.25; 95% CI 0.08-0.75; p < 0.01) and perforation diameter ≤ 5 mm (OR 0.13; 95% CI 0.04-0.36; p < 0.01) as significant independent clinical factors for successful conservative management of duodenal ulcer perforation.

CONCLUSIONS

Urgent endoscopy in gastroduodenal perforation enabled primary diagnosis and perforation site identification, and facilitated deciding the management strategy.

A Rare Case of Delayed Perigastric Abscess after Curative Resection of Early Gastric Cancer by Uncomplicated Endoscopic Submucosal Dissection: Successful Treatment with Endoscopic Ultrasound-guided Drainage

A 72-year-old man had undergone uncomplicated endoscopic submucosal dissection (ESD) with en bloc resection of a localized 20-mm IIc lesion in the anterior wall of the gastric angle. Twenty-eight days later, he was re-admitted with epigastric pain of one-week duration. Contrast-enhanced computed tomography (CT) revealed a 60-mm mass bordered by viscera; repeat endoscopy confirmed a smooth elevated submucosal tumor at the greater curvature on the oral side of the post-ESD ulcer. We diagnosed him with a perigastric abscess as a complication of ESD and performed endoscopic ultrasound-guided drainage. Subsequently, the symptoms and blood inflammatory parameters improved, and follow-up CT showed the disappearance of the abscess.

Step-clipping method can improve the detectability of the target lesion in colonic diverticular bleeding

Background and study aims  Despite the information regarding extravasation from contrast-enhanced computed tomography (CECT), the detectability of the target diverticulum by colonoscopy remains unsatisfactory in colonic diverticular bleeding (CDB). The lack of common signs recognizable on CT and endoscopic images makes it difficult to set a region of interest; however, this can be overcome with the "step-clipping" method, a strategic marking technique for revealing the target. We aimed to investigate the clinical performance of the step-clipping method in patients with CDB. Patients and methods  Eighty-seven patients diagnosed with CDB with extravasation using CECT who underwent colonoscopy between August 2007 and February 2020 were included. Patients were divided into two categories: the traditional group (those who underwent colonoscopy from August 2007 to May 2017, n = 54) and the step-clipping group (those who underwent colonoscopy from June 2017 to February 2020, n = 33). Results  The detection rate for the responsible diverticulum was significantly higher in the step-clipping group than in the traditional group (94 % vs 63 %; P  = .0013). The step-clipping group had a shorter average search time during colonoscopy (9.6 vs 40.5 minutes; P  < .0001) and lower re-bleeding rate after the initial colonoscopy (6 % vs 26 %; P  = .02) than the traditional group, which facilitated earlier hospital discharge (5.4 vs 6.8 days; P  = .027). Conclusions  Colonoscopy using the step-clipping method can improve the detectability of the target lesion within a shorter time, thus leading to lower re-bleeding rates and earlier hospital discharge.

Bile pigment in small-bowel water content may reflect bowel habits: a retrospective analysis of a capsule endoscopy imaging series

Background

Pigmented bile salts darken the small-bowel lumen and are present with bile acid, which is involved in the development of bowel habits. The small-bowel water content (SBWC) in the ileum could represent the colonic environment, but no studies have focused on this feature. However, measurement of crude SBWC can be challenging because of the technical difficulty of the endoscopic approach without preparation. Our aim was to evaluate optically active bile pigments in the SBWC of patients with abnormal bowel habits using capsule endoscopy (CE) to investigate the impact of bile acid on bowel habits.

Methods

The study population included 37 constipated patients, 20 patients with diarrhea, and 77 patients with normal bowel habits who underwent CE between January 2015 and May 2018. Patients with secondary abnormal bowel habits were excluded. In addition to conventional imaging, we used flexible spectral imaging color enhancement (FICE) setting 1 imaging, in which the effects of bile pigments on color are suppressed. Intergroup color differences of SBWC in the ileum (ΔE) were evaluated from conventional and FICE setting 1 images. Color values were assessed using the CIE L*a*b* color space. Differences in SBWC lightness (black to white, range 0–100) were also evaluated.

Results

The ΔE values from the comparison of conventional images between patients with constipation and with normal bowel habits and between patients with diarrhea and with normal bowel habits were 12.4 and 11.2, respectively. These values decreased to 4.4 and 3.3, respectively, when FICE setting 1 images were evaluated. Patients with constipation and diarrhea had significantly brighter (34.4 versus 27.6, P < .0001) and darker (19.6 versus 27.6, P < .0001) SBWC lightness, respectively, than patients with normal bowel habits. The FICE setting 1 images did not reveal significant differences in SBWC lightness between those with constipation and with normal bowel habits (44.1 versus 43.5, P = .83) or between those with diarrhea and with normal bowel habits (39.1 versus 43.5, P = .20).

Conclusions

Differences in SBWC color and darkness in the ileum appear to be attributable to bile pigments. Therefore, bile pigments in SBWC may reflect bowel habits.

Successful Endoscopic Sclerotherapy Using Polidocanol for Small Bowel Hemangioma

Small-bowel hemangiomas are a possible source of gastrointestinal bleeding for which there is no established treatment approach. In this report, we describe the case of a 58-year-old woman who presented with hematochezia and who was diagnosed with small bowel hemangioma. She was successfully treated using endoscopic sclerotherapy. Initial capsule endoscopy revealed bleeding in the ileum. Subsequent double-balloon enteroscopy showed a 2-cm, bluish-purple, ileal submucosal tumor with an overlying protrusion. The lesion was responsible for the hematochezia and was treated with intralesional injection of polidocanol. The hematochezia completely resolved and at 4 months after sclerotherapy, the size of the lesion was significantly reduced.

A new procedure combining local resection with endoscopic submucosal dissection for low rectal tumor: a four-case series

Rectal tumors are traditionally resected by proctectomy to ensure the achievement of negative margins, an approach associated with an adverse impact on subsequent quality of life due to sequelae such as permanent stoma and urinary and sexual dysfunction. Many studies have now demonstrated that recurrence after local excision of early rectal tumors is significantly higher than would typically be expected. We have developed a new procedure, described herein, that combines local resection with endoscopic submucosal dissection for low rectal tumor. We report four consecutive cases (three submucosal tumors and one tumor with clinical deep submucosal invasion) treated at Hiroshima City Asa Citizens Hospital between January 2009 and March 2018. The mean duration of the procedure was 137 minutes. The en bloc resection and histologically complete resection rates were 100 %. Delayed bleeding and perforation rates were 0 %. Postoperative complications were fever and anal pain (one case each). All patients recovered with conservative therapy. No recurrence was found in any of the four patients during a follow-up period of 56 months. Our combined endoscopic and surgical procedure for low rectal tumors enabled definite negative vertical margins, reduced tumor volume, allowed for accurate pathological diagnosis, preserved rectal function, and aided the decision on additional therapy.

The 'step-clipping' method: a guide for identifying a previously bleeding colonic diverticulum

Background and study aims  Unsatisfactory detectability of a previously bleeding diverticulum by colonoscopy results from difficulty in precisely locating the target lesion, even with presence of an extravasation on contrast-enhanced computed tomography (CECT). This study aimed to evaluate the usefulness of the step-clipping method to overcome this limitation. Patients and methods  Step-clipping was indicated for patients with colonic diverticular bleeding and presence of extravasation on CECT, but with absence of active bleeding on subsequent colonoscopy. The target diverticulum was identified by comparing computed tomography images before and after step clipping, which provided a positional relationship between each clip and the target lesion. Results  Based on data from 21 consecutive cases meeting our inclusion criteria (14 men and 7 women; mean age, 73.2 years), the target diverticulum was endoscopically identified in 20 cases (95 %), in a median time of 5 minutes, and successfully treated. No adverse events were observed with the step-clipping method. Conclusion  Step-clipping provided easy guidance to the target site for treatment in a short time, despite spontaneous cessation of bleeding at the diverticulum.

[A case of ruptured posterior superior pancreaticoduodenal artery aneurysm successfully treated by emergency transcatheter embolization]

A man in his 40s with no remarkable past medical history was referred to our hospital with acute exacerbation of nonspecific epigastric pain by another hospital on the morning of the day of presentation. Though vital signs were stable, tenderness and guarding were observed over the entire abdomen. Contrast-enhanced computed tomography (CT) revealed a giant retroperitoneal hematoma due to a ruptured aneurysm close to the superior mesenteric artery. Emergency angiography of the superior mesenteric artery detected a ruptured 2-mm pseudoaneurysm of the posterior superior pancreaticoduodenal artery, for which embolization was immediately performed. The postoperative course was good, with the patient complaining only of transient abdominal pain due to exclusion of the hematoma on hospital day 6. His clinical symptoms disappeared with conservative treatment, and the patient was discharged on hospital day 18. Complete occlusion of the aneurysm and reduction of the hematoma was confirmed on follow-up CT. Pancreaticoduodenal artery aneurysm is an uncommon visceral artery aneurysm, and ruptured aneurysms typically result in fatal hemorrhage and high mortality. We herein report a case of ruptured aneurysm of the posterior pancreaticoduodenal artery where emergency transcatheter arterial embolization was able to save the patient's life. We also review 116 cases of pancreaticoduodenal artery aneurysm reported in Japanese literature.

Use of anticoagulants increases risk of bleeding after colorectal endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

Japanese guidelines for gastroenterological endoscopy have recommended temporary withdrawal of anticoagulants (warfarin, direct oral anticoagulants [DOAC], or heparin) to prevent hemorrhagic complications during endoscopic submucosal dissection (ESD) for colorectal neoplasias (CRNs). However, serious thrombosis might occur during temporary withdrawal of anticoagulants. The current study aimed to evaluate outcomes with anticoagulants in patients undergoing ESD for CRNs.

PATIENTS AND METHODS

 This study was a single-institution retrospective cohort study based on clinical records. We assessed 650 consecutive patients with 698 CRNs who underwent ESD at Hiroshima University Hospital between December 2010 and June 2016. The patients were divided into three groups: the warfarin group (19 patients with 19 CRNs), DOAC group (7 patients with 9 CRNs), and no-antithrombotics group (624 patients with 670 CRNs). We replaced warfarin with heparin 3 to 5 days before endoscopy. Although DOAC was suspended on the morning of endoscopy, we did not replace heparin.

RESULTS

 Bleeding after the procedure occurred in 26.3 % (5/19), 22.0 % (2/9), and 2.7 % (18/670) of patients in the warfarin, DOAC, and no-antithrombotics groups, respectively. In the warfarin group, four patients who bled after the procedure took not only warfarin but also other antiplatelets. En bloc resection rates were 94.7 % (18/19), 100 % (9/9), and 96.6 % (647/670) in the warfarin, DOAC, and no-antithrombotics groups, respectively. No patients experienced ischemic events in the perioperative period.

CONCLUSIONS

Among patients undergoing ESD for CRNs, risk of bleeding was higher among patients who took anticoagulants than among those who did not. In particular, careful attention to patients who took antiplatelets in addition to warfarin before ESD for CRNs is warranted.

Effectiveness and safety of endoscopic radial incision and cutting for severe benign anastomotic stenosis after surgery for colorectal carcinoma: a three-case series

Benign colonic anastomotic stenosis sometimes occurs after surgical resection and usually requires surgical or endoscopic dilation. Limited data are available on the effectiveness and safety of the endoscopic radial incision and cutting (RIC) method at sites other than the esophagus. The aim of this retrospective study was to investigate the effectiveness and safety of RIC dilation for severe benign anastomotic colonic stenosis. Subjects were 3 men (median age 72 years, range 65 - 76 years) who developed severe benign anastomotic stenosis after surgical resection for colorectal carcinoma and were subsequently treated by RIC dilation at Hiroshima City Asa Citizens Hospital between May 2014 and December 2016. Severe anastomotic stenosis was defined as a narrowed anastomosis through which a standard colonoscope could not be passed. The median interval from surgery to RIC was 21 months (range 9 - 29 months). RIC was successful in all 3 patients and reduced the severity of dyschezia postoperatively; 2 patients experienced improvement after a single RIC session and the other after 6 RIC sessions. No treatment-related adverse events or re-stenosis requiring repeat dilation was noted during a median follow-up of 27 months (range 8 - 37 months). Our findings indicate that the RIC technique can be applied safely and effectively to various sites in the colon, avoiding the need for reoperation.

Arteriosclerosis Is a Major Predictor of Small Bowel Vascular Lesions

BACKGROUND

Most studies have focused on evaluating the association between the presence of small bowel vascular lesions (SBVLs) and patients' comorbidities.

AIMS

We sought to uncover a more fundamental indicator that may predict the presence of SBVLs by considering atherosclerosis qualitatively and quantitatively.

METHODS

We enrolled 79 consecutive patients with obscure gastrointestinal bleeding who had undergone computed tomography (CT) and capsule endoscopy or double-balloon endoscopy from January 2015 to June 2017. The SBVL frequency, type, and location, and the relationship between the presence of SBVLs and the patients' clinical characteristics were evaluated. Arterial wall calcification was assessed on unenhanced CT images, and a modified Agatston scoring system was used to determine the abdominal aorta calcium scores.

RESULTS

Of the 27 (34%) patients with SBVLs, 15 (19%) had type 1a, 12 (15%) had type 1b, and 2 (3%) had type 2a SBVLs. Most of the lesions were located in the jejunum. Cardiovascular disease (P = .017), chronic kidney disease (P = .025), and arteriosclerosis (P = .0036) were associated with the presence of SBVLs. Subsequent multivariate analysis revealed that arteriosclerosis (odds ratio [OR] 7.29; 95% confidence interval [CI] 1.13-143.9) and superior mesenteric artery calcification (OR 16.3; 95% CI 3.64-118.6) were independent predictors of the presence of SBVLs. The modified Agatston score was significantly higher in SBVL cases than in non-SBVL cases (6384 vs. 2666, P = .0023).

CONCLUSIONS

Arteriosclerosis, especially increased superior mesenteric artery calcification, is associated with an increased likelihood of SBVLs.

Clinicopathologic and endoscopic features of early-stage colorectal serrated adenocarcinoma

Background

Serrated adenocarcinoma (SAC) is a distinct colorectal carcinoma variant that accounts for approximately 7.5% of all advanced colorectal carcinomas. While its prognosis is worse than conventional carcinoma, its early-stage clinicopathologic features are unclear. We therefore aimed to clarify the clinicopathologic and endoscopic characteristics of early-stage SACs.

Methods

Forty consecutive early-stage SAC patients at Hiroshima University Hospital were enrolled; SACs were classified into epithelial serration (Group A, n = 17) and non-epithelial serration (Group B, n = 23) groups. Additionally, we classified serrated adenoma into 4 types: sessile serrated adenoma (SSA), traditional serrated adenoma (TSA), unclassified, and non-serrated adenoma type.

Results

There were significant differences between Groups A and B in terms of tumor size (27.6 vs. 43.1 mm), incidences of T1 carcinoma (71% vs. 13%), and having the same color as normal mucosa (47% vs. 17%), respectively (p <0.01). In SACs >20 mm, the incidence of T1 carcinoma in Group A (70%) was significantly greater than that in Group B (13%) (p <0.05). There were significant differences in ‘Japan NBI Expert Team’ type 3 and type V pit pattern classifications between the 2 groups. The average TSA-type tumor size (42.6 mm) was significantly larger than that of the SSA (17.2 mm) and non-serrated component types (18.3 mm). The incidences of submucosal invasion in SSA- (80%), unclassified- (100%), and non-serrated-type (100%) tumors were significantly higher than that in the TSA type (11%).

Conclusions

Epithelial serration in the cancerous area and a non-TSA background indicated aggressive behavior in early-stage SACs.

Clinical impact of surveillance colonoscopy using magnification without diminutive polyp removal

BACKGROUND AND AIM

In Western countries, endoscopic removal of all adenomas during colonoscopy is recommended. The present study evaluates the usefulness of magnifying colonoscopy without removal of diminutive (≤5 mm) colorectal polyps.

METHODS

Patients with diminutive polyps who were observed for over 5 years using magnification at Hiroshima University Hospital were selected retrospectively. Lesions ≥6 mm in size, depressed lesions, and lesions with type V pit pattern were indications for endoscopic resection. We investigated the characteristics of lesions indicated for endoscopic resection detected on surveillance colonoscopy and the risk factors for the incidence of lesions indicated for endoscopic resection.

RESULTS

A total of 706 consecutive patients were enrolled. Sixty-eight lesions indicated for endoscopic resection were detected, averaging 9.0 ± 4.8 mm, and 33 (49%) lesions were located in the right colon. Pathological diagnoses were adenoma, Tis carcinoma, and T1 carcinoma in 58 (85%), eight (12%), and two (3%) lesions, respectively. Five lesions were considered to grow from previously detected diminutive polyps. Relative risks for the incidence of a lesion indicated for endoscopic resection were 1.76 (95% confidence interval [CI], 1.004-3.23) for males compared with females, 3.76 (95% CI, 2.03-7.50) for more than three polyps at initial colonoscopy compared with one polyp, and 2.84 (95% CI, 1.43-5.24) for patients with carcinoma at initial colonoscopy compared with patients with no lesion indicated for endoscopic resection. Nine carcinomas were resected endoscopically.

CONCLUSION

Diminutive low-grade adenomas detected by using magnifying colonoscopy may not necessarily require removal.

Diagnostic performance of Japan NBI Expert Team classification for differentiation among noninvasive, superficially invasive, and deeply invasive colorectal neoplasia

BACKGROUNDS AND AIMS

The Japan NBI Expert Team (JNET) classification is the first universal narrow-band imaging magnifying endoscopic classification of colorectal tumors. Considering each type in this classification, the diagnostic ability of Type 2B is the weakest. Generally, clinical behavior is believed to be different in each gross type of colorectal tumor. We evaluated the differences in the diagnostic performance of JNET classification for each gross type (polypoid and superficial) and examined whether the diagnostic performance of Type 2B could be improved by subtyping.

METHODS

We analyzed 2933 consecutive cases of colorectal lesions, including 136 hyperplastic polyps/sessile serrated polyps, 1926 low-grade dysplasias (LGDs), 571 high-grade dysplasias (HGDs), and 300 submucosal (SM) carcinomas. We classified lesions as polypoid and superficial type and compared the diagnostic performance of the classification system in each type. Additionally, we subtyped Type 2B into 2B-low and 2B-high based on the level of irregularity in surface and vessel patterns, and we evaluated the relationship between the subtypes and histology, as analyzed separately for polypoid and superficial types. We also estimated interobserver and intraobserver variability.

RESULTS

The diagnostic performance of JNET classification did not differ significantly between polypoid and superficial lesions. Ninety-nine percent of Type 2B-low lesions were LGDs, HGDs, or superficial submucosal invasive (SM-s) carcinomas. In contrast, 60% of Type 2B-high lesions were deep submucosal invasive (SM-d) carcinomas. The results were not different between each gross type. Interobserver and intraobserver agreements for Type 2B subtyping were good, with kappa values of .743 and .786, respectively.

CONCLUSIONS

Type 2B subtyping may be useful for identifying lesions that are appropriate for endoscopic resection. JNET classification and Type 2B sub classification are useful criteria, regardless of gross type.

Clinical impact and characteristics of the narrow-band imaging magnifying endoscopic classification of colorectal tumors proposed by the Japan NBI Expert Team

BACKGROUND AND AIMS

The Japan NBI Expert Team (JNET) was established in 2011 and has proposed a universal narrow-band imaging (NBI) magnifying endoscopic classification of colorectal tumors. The aim of this study was to evaluate the clinical usefulness of the JNET classification for colorectal lesions.

METHODS

We analyzed 2933 colorectal lesions, which were diagnosed by NBI magnifying observation before endoscopic treatment or surgery. The colorectal lesions consisted of 136 hyperplastic polyps/sessile serrated polyps (HPs/SSPs), 1926 low-grade dysplasia (LGD), 571 high-grade dysplasia (HGD), 87 superficial submucosal invasive (SM-s) carcinomas, and 213 deep submucosal invasive (SM-d) carcinomas. We evaluated the relationship between the JNET classification and the histologic findings of these lesions.

RESULTS

The sensitivity, specificity, positive and negative predictive values, and accuracy of Type 1 lesions for the diagnosis of HP/SSP were, respectively, 87.5%, 99.9%, 97.5%, 99.4%, and 99.3%; of Type 2A lesions for the diagnosis of LGD were 74.3%, 92.7%, 98.3%, 38.7%, and 77.1%; of Type 2B lesions for the diagnosis of HGD/SM-s carcinoma were 61.9%, 82.8%, 50.9%, 88.2%, and 78.1%; for Type 3 lesions for the diagnosis of SM-d carcinoma were 55.4%, 99.8%, 95.2%, 96.6%, and 96.6%, respectively.

CONCLUSIONS

Types 1, 2A, and 3 of the JNET classification were very reliable indicators for HP/SSP, LGD, and SM-d carcinoma, respectively. However, the specificity and positive predictive value of Type 2B were relatively lower than those of others. Therefore, an additional examination such as pit pattern diagnosis using chromoagents is necessary for accurate diagnosis of Type 2B lesions.

Long-term outcomes after endoscopic submucosal dissection for superficial colorectal tumors

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an effective procedure for en bloc resection of superficial colorectal tumors regardless of tumor size or location. However, there are few reports on long-term outcomes for patients with superficial colorectal tumors after ESD. We therefore aimed to evaluate the long-term outcomes after ESD for superficial colorectal tumors.

METHODS

ESD was performed on 257 colorectal tumors in 255 consecutive patients at Hiroshima University Hospital between June 2003 and July 2010. We investigated the following variables: patient characteristics, the American Society of Anesthesiologists score, tumor location, tumor size, growth type, histology, en bloc resection rate, achievement of curative resection, procedure time, and adverse events. The 5-year overall survival (OS), 5-year disease-specific survival (DSS), local recurrence, and metachronous tumor occurrence were also analyzed.

RESULTS

We identified 224 tumors in 222 patients who were confirmed dead or had follow-up data for more than 5 years. After a median follow-up of 79 months, 5-year OS and DSS rates were 94.6% and 100%, respectively. The local recurrence rate (1.5%) was significantly higher in patients undergoing piecemeal resection (9.1%) compared with en bloc resection (0.6%), in cases of histologic incomplete resection compared with complete resection, and in cases of non-R0 resection compared with R0 resection. The rates of total number of tumors (≥6 mm) and carcinoma metachronous tumors after ESD without additional surgical resection were 18.9% (38/201) and 4.0% (8/201), respectively.

CONCLUSIONS

Long-term outcomes after ESD for superficial colorectal tumors are favorable. Patients should be surveyed for both local recurrence and metachronous tumors after ESD.

Clinical impact of dual red imaging in colorectal endoscopic submucosal dissection: a pilot study

BACKGROUND

Dual red imaging (DRI), a novel image-enhanced endoscopic technique, is expected to improve visibility of thin vessels, but no reports of the clinical use of DRI in colorectal endoscopic submucosal dissection (ESD) have been published. We aimed to compare the visibility of vessels, demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine, and fibrosis on DRI with that on white light imaging (WLI). We applied the principle of DRI to the image of the submucosal layer during colorectal ESD as a pilot study.

METHODS

A total of seven physicians compared 17 DRI images to the corresponding WLI images in colorectal ESD. The physicians compared the number of arteries identified on DRI with the actual number of arteries. The physicians rated the visibility of vessels, the demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine, and fibrosis. Inter-observer agreement was also examined using the kappa statistic.

RESULTS

Visibility of vessels and the demarcation line between the submucosal and muscle layers after injection of hyaluronate sodium with minute indigo carmine improved with the use of DRI compared with that using WLI. DRI can discriminate between arteries and veins clearly through the color of the vessels.

CONCLUSIONS

DRI improves the visibility of vessels, especially that of arteries, as they appear orange, and the demarcation line of the muscle layer. DRI may help to make colorectal ESD safer and faster.

Pedunculated-type T1 colorectal carcinoma with lung carcinoma metastasis at the deepest invasive portion

We present a rare case of colorectal T1 carcinoma with metastasis of previous lung carcinoma found at the deepest invasive portion. A 61-year-old man presented with cervical lymphadenopathy 18 years after undergoing surgery for right lung carcinoma [poorly differentiated adenocarcinoma stage IIb (T3N0M0)]. Contrast-enhanced computed tomography showed enlarged lymph nodes (LNs) in the neck and mediastinal regions. Combined hybrid-F-fluorodeoxyglucose positron emission-computerized tomography showed increased radionuclide uptake in multiple cervical LNs and mediastinal LNs. LN biopsy revealed a poorly differentiated adenocarcinoma, suspected to be a metastatic tumor of the lung. Subsequent colonoscopy revealed a pedunculated-type lesion with a depressed area in the ascending colon. We performed polypectomy as total excisional biopsy; this tumor was composed mainly of moderately differentiated adenocarcinoma, partially mixed with mucinous adenocarcinoma. The pathological findings of the invasive front of the colorectal carcinoma showed poorly differentiated adenocarcinoma with a morphological pattern similar to that of the previous lung carcinoma. Furthermore, immunohistochemical results for the histological type of the deepest invasive portion of the tissue specimen were positive for thyroid transcription factor-1 but negative for Caudal-type homeobox 2. From these morphological and immunohistochemical findings, the final diagnosis was moderately differentiated lung carcinoma, pTX N3 M1b (LN, colon) Stage IV.

Clinical usefulness of a single-use splinting tube for poor endoscope operability in deep colonic endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

Poor endoscope operability remains a significant challenge during colorectal endoscopic submucosal dissection (ESD). We retrospectively evaluated the experience and clinical usefulness of a new single-use splinting tube in deep colonic ESD in the setting of poor scope operability.

PATIENTS AND METHODS

Among 691 patients with colorectal tumors treated with ESD at Hiroshima University Hospital between November 2009 and July 2015, we analyzed 20 consecutive patients who underwent deep colonic ESD using a single-use splinting tube because of poor scope operability. Poor operability was defined as paradoxical movement of the endoscope, poor control with adhesions, and lesion motion with heartbeat or breathing. Technical and clinical success rates and adverse events were assessed.

RESULTS

Paradoxical movement and poor control with adhesions were improved in all cases using the single-use splinting tube. The en bloc resection rate was 95 % (19/20) and histological en bloc resection rate was 100 % (20/20). There were no complications related to use of the splinting tube.

CONCLUSIONS

Use of a single-use splinting tube helped to overcome poor scope operability in deep colonic ESD.

Clinical significance and validity of the subclassification for colorectal laterally spreading tumor granular type

BACKGROUND AND AIM

Colorectal laterally spreading tumor granular type (LST-G) is generally divided into two subtypes based on morphology. Here, we retrospectively investigated the clinical significance of a concrete, objective LST-G subclassification.

METHODS

This study examined 636 consecutive cases that were resected endoscopically or surgically. LST-G was subclassified as follows: Type 1, a lesion with homogenous uniform granules with uniform (<5 mm) nodules; Type 2, a lesion with granules and small nodules (≥5 mm, <10 mm); or Type 3, a lesion accompanied by large nodules (≥10 mm). For the validation study, 194 images were compiled from 97 cases investigated using conventional colonoscopy and chromoendoscopy with indigo carmine dye spraying. Images were distributed in a randomized order to students without prior endoscopy experience, less-experienced endoscopists (LEE group), and highly experienced endoscopists (HEE group). Diagnostic accuracy and interobserver agreement were then evaluated.

RESULTS

There was no submucosal invasion in Type 1 lesions. The incidence of deep submucosal invasive carcinoma was higher for Type 3 lesions than for Type 2 lesions. Interobserver agreement was good in each group. Diagnostic accuracy was higher in the HEE group than in the student and LEE groups. Chromoendoscopy had a higher accuracy rate than conventional colonoscopy in the LEE and HEE groups (LEE, 0.74 vs 0.69, P < 0.05; HEE, 0.84 vs 0.78, P < 0.05).

CONCLUSIONS

This subclassification of LST-G according to the diameters of granules and nodules was both useful for choosing therapeutic strategies in the clinical setting and universally applicable.

Long-term outcomes after treatment for T1 colorectal carcinoma

PURPOSE

Long-term outcomes of patients with T1 colorectal carcinoma (CRC) treated by endoscopic resection (ER) or surgical resection are unclear in relation to the curative criteria in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines. The aim of this study was to retrospectively compare the long-term outcomes among patients with T1 CRC in relation to the treatment methods.

METHODS

We examined 322 T1 CRC cases treated between January 1992 and August 2008 at Hiroshima University Hospital. Patients who did not meet the curative criteria in the JSCCR guidelines were defined as "non-endoscopically curable" and classified into three groups: underwent ER alone (group A: 45 patients), underwent additional surgery after ER (group B: 106 patients), and underwent surgical resection alone (group C: 92 patients).

RESULTS

Of the 322 T1 CRC patients, 79 were categorized as endoscopically curable and 243 as non-endoscopically curable. Among the endoscopically curable T1 CRC patients, recurrence and 5-year OS rates were 0 and 94.2%, respectively. In groups A, B, and C, recurrence rates were 4.4, 6.6, and 4.3%, and OS rates were 85.6, 95.1, and 96.3%, respectively (p < 0.05). Local recurrence or distant/lymph node metastasis was observed in 13 patients (group A: 2; group B: 7; group C: 4). Death due to primary CRC occurred in six patients (group B: 4; group C: 2).

CONCLUSION

Long-term outcomes support the curative criteria according to the JSCCR guidelines. ER for T1 CRC did not worsen clinical outcomes in cases that required additional surgical resection.

Endoscopic submucosal dissection for anorectal tumor with hemorrhoids close to the dentate line: a multicenter study of Hiroshima GI Endoscopy Study Group

BACKGROUND

The lower rectum close to the dentate line has distinct characteristics, making endoscopic submucosal dissection (ESD) of tumors challenging. We assessed clinical outcomes of ESD for such patients with hemorrhoids.

METHODS

Sixty-four patients (mean age, 68 years) underwent ESD for anorectal tumors close to the dentate line. We divided patients into those with (Group A, 45 patients) and without hemorrhoids (Group B, 19 patients). We examined en bloc and histological en bloc resection rates, procedure time, complication rates, and postoperative prognosis after ESD.

RESULTS

The mean tumor size was 43 mm. Histologic diagnoses were adenoma (42 %, 27/64), carcinoma in situ (44 %, 28/64), and T1 carcinoma (14 %, 9/64). There was no significant difference in en bloc resection (93 %, 42/45 vs. 95 %, 18/19) or postoperative bleeding rates (16 %, 7/45 vs. 11 %, 2/19) between Groups A and B, respectively. The mean procedural durations were 120 and 124 min, respectively, in Groups A and B. No perforations occurred. There was no significant difference in postoperative anal pain rate between Groups A (18 %, 8/45) and B (16 %, 3/19), and it resolved within a few days in all cases. There was one case of stricture in Group B. Two patients with T1 carcinoma underwent additional surgery, one underwent chemotherapy, and five had no additional treatment. No recurrence occurred during the follow-up period of 38 months.

CONCLUSIONS

ESD is safe and effective for anorectal tumors close to the dentate line in patients with hemorrhoids.

Risk of bleeding after endoscopic submucosal dissection for colorectal tumors in patients with continued use of low-dose aspirin

BACKGROUND

Although Japanese guidelines proposed by the Japan Gastroenterological Endoscopy Society for endoscopic submucosal dissection (ESD) for colorectal tumors recommend continued use of low-dose aspirin (LDA), this strategy is controversial. It was our practice to interrupt LDA therapy 5-7 days before ESD until December 2010, when we instituted the new guidelines and performed ESD without interrupting LDA therapy. The aim of the present study was to confirm the validity of the noninterrupted use of LDA inpatients undergoing ESD for colorectal tumors.

METHODS

We studied 582 consecutive patients with 609 colorectal tumors who underwent ESD at Hiroshima University Hospital between January 2006 and July 2014. The patients comprised three groups: LDA-interrupted group (13 patients with 13 colorectal tumors), LDA-continued group (28 patients with 31 colorectal tumors), and no anticoagulant/antiplatelet group (541 patients with 565 colorectal tumors).

RESULTS

The en bloc resection rate was 100% (13/13) in the LDA-interrupted group and 90.3% (28/31) in the LDA-continued group. Incidences of poor bleeding control during the procedure and bleeding after the procedure were 7.7% (1/13) and 15.4% (2/13) of patients, respectively, in the LDA-interrupted group, and 3.2% (1/31) and 16.1% (5/31) of patients, respectively, in the LDA-continued group. No patients experienced ischemic events in the perioperative period.

CONCLUSIONS

Our data suggest that continued use of LDA increased the risk of bleeding after ESD for colorectal tumors compared with nonuse of anticoagulant/antiplatelets. No significant difference was seen between the LDA-continued group and the LDA-interrupted group.

Early squamous cell carcinoma of the anal canal resected by endoscopic submucosal dissection

The standard treatment approach for squamous cell carcinoma (SCC) of the anal canal includes abdominoperineal resection and chemoradiotherapy. However, there are currently very few reports of early SCC of the anal canal resected by endoscopic submucosal dissection (ESD). We report 2 rare cases of SCC of the anal canal resected by ESD. In case 1, a 66-year-old woman underwent a colonoscopy due to blood in her stool, and an elevated lesion, 15 mm in size, was identified from the rectum to the dentate line of the anal canal on internal hemorrhoids. The lesion was diagnosed as an early SCC of the anal canal, and ESD was successfully performed. The histopathological diagnosis was SCC in situ. In case 2, a 71-year-old woman underwent a colonoscopy due to constipation, and an elevated lesion, 25 mm in size, was identified from the dentate line to the anal canal. The lesion was diagnosed as early-stage SCC of the anal canal, and ESD was successfully performed. The histopathological diagnosis was SCC in situ. No complications or recurrence after ESD occurred in either case.

Towards safer and appropriate application of endoscopic submucosal dissection for T1 colorectal carcinoma as total excisional biopsy: future perspectives

According to the Japanese Society for Cancer of the Colon and Rectum Guidelines 2014 for the Treatment of Colorectal Cancer, cases with T1 colorectal carcinoma should be considered for additional colectomy with lymph node dissection when histologically complete en bloc resection is endoscopically carried out and when one of the four risk factors listed below is present. These four risk factors are: (i) submucosal (SM) invasion depth ≥1000 μm; (ii) positive vascular invasion; (iii) poorly differentiated adenocarcinoma, signet ring cell carcinoma, or mucinous carcinoma; and (iv) grade 2/3 budding at the deepest part of SM invasion. However, the probability of lymph node metastasis is extremely low if none of these risk factors are present, with the exception of SM invasion depth ≥1000 μm. Consequently, it is assumed that there will be an increasing number of cases where no additional surgery is done, or cases of moderate invasive carcinoma in which endoscopic treatment is carried out to achieve an excisional biopsy, for which complete resection is applicable. In these cases, the preoperative diagnosis, resection techniques such as endoscopic submucosal dissection, features of resected specimens, and the accuracy of pathological diagnosis are all extremely important.