How Does Omitting Additional Surgery After Local Excision Affect the Prognostic Outcome of Patients With High-risk T1 Colorectal Cancer?

OBJECTIVE: To investigate how omitting additional surgery after local excision (LE) affects patient outcomes in high-risk T1 colorectal cancer (CRC). BACKGROUND: It is debatable whether additional surgery should be performed for all patients with high-risk T1 CRC regardless of the tolerability of invasive procedures. METHODS: Patients who had received LE for T1 CRC at the Japanese Society for Cancer of the Colon and Rectum institutions between 2009 and 2016 were analyzed. Those who had received additional surgical resection and those who did not were matched one-on-one by the propensity score-matching method. A total of 401 propensity score-matched pairs were extracted from 1975 patients at 27 Japanese Society for Cancer of the Colon and Rectum institutions and were compared. RESULTS: Regional lymph node metastasis was observed in 31 (7.7%) patients in the LE + surgery group. Comparatively, the incidence of oncologic adverse events was low in the LE-alone group, such as the 5-year cumulative risk of local recurrence (4.1%) or overall recurrence (5.5%). In addition, the difference in the 5-year cancer-specific survival between the LE + surgery and LE-alone groups was only 1.8% (99.7% and 97.9%, respectively), whereas the 5-year overall survival was significantly lower in the LE-alone group than in the LE + surgery group [88.5% vs 94.5%, respectively ( P = 0.002)]. CONCLUSIONS: Those who had decided to omit additional surgery at the dedicated center for CRC treatment presented a small number of oncologic events and a satisfactory cancer-specific survival, which may suggest an important role of risk assessment regarding nononcologic adverse events to achieve a best practice for each individual with high-risk T1 tumors.

Long-Term Outcomes of Additional Surgery After Endoscopic Resection Versus Primary Surgery for T1 Colorectal Cancer.

INTRODUCTION: There is considerable concern about whether endoscopic resection (ER) before additional surgery (AS) for T1 colorectal cancer (CRC) has oncologically potential adverse effects. Therefore, the aim of this study was to compare the long-term outcomes, including overall survival (OS), of patients treated with AS after ER vs primary surgery (PS) for T1 CRC using a propensity score-matched analysis from a large observational study. METHODS: This study investigated 6,105 patients with T1 CRC treated with either ER or surgical resection between 2009 and 2016 at 27 high-volume Japanese institutions, with those undergoing surgery alone included in the PS group and those undergoing AS after ER included in the AS group. Propensity score matching was used for long-term outcomes of mortality and recurrence analysis. RESULTS: After propensity score matching, 1,219 of 2,438 patients were identified in each group. The 5-year OS rates in the AS and PS groups were 97.1% and 96.0%, respectively (hazard ratio: 0.72, 95% confidence interval: 0.49-1.08), indicating the noninferiority of the AS group. Moreover, 32 patients (2.6%) in the AS group and 24 (2.0%) in the PS group had recurrences, with no significant difference between the 2 groups (odds ratio: 1.34, 95% confidence interval: 0.76-2.40, P = 0.344). DISCUSSION: ER before AS for T1 CRC had no adverse effect on patients' long-term outcomes, including the 5-year OS rate. ER is a viable first-line treatment option for endoscopically resectable T1 CRC.

Treatment Decision for Locally Resected T1 Colorectal Carcinoma-Verification of the Japanese Guideline Criteria for Additional Surgery Based on Long-Term Clinical Outcomes.

INTRODUCTION: To verify the value of the pathological criteria for additional treatment in locally resected pT1 colorectal carcinoma (CRC) which have been used in the Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines since 2009. METHODS: We enrolled 4,667 patients with pT1 CRC treated at 27 institutions between July 2009 and December 2016 (1,257 patients with local resection alone [group A], 1,512 patients with additional surgery after local resection [group B], and 1,898 patients with surgery alone [group C]). All 5 factors of the JSCCR guidelines (submucosal resection margin, tumor histologic grade, submucosal invasion depth, lymphovascular invasion, and tumor budding) for lymph node metastasis (LNM) had been diagnosed prospectively. RESULTS: Any of the risk factors were present in 3,751 patients. The LNM incidence was 10.4% (95% confidence interval 9.4-11.5) in group B/C patients with risk factors, whereas it was 1.8% (95% confidence interval 0.4-5.3) in those without risk factors ( P < 0.01). In group A, the incidence of recurrence was 3.6% in patients with risk factors, but it was only 0.4% in patients without risk factors ( P < 0.01). The disease-free survival rate of group A patients classified as risk positive was significantly worse than those of groups B and C patients. However, the 5-year disease-free survival rate in group A patients with no risk was 99.6%. DISCUSSION: Our large-scale real-world multicenter study demonstrated the validity of the JSCCR criteria for pT1 CRC after local resection, especially regarding favorable outcomes in patients with low risk of LNM.

Vertical margin distance in T1 colorectal carcinoma resected by endoscopic submucosal dissection affects prognosis after additional surgery.

PURPOSE : A vertical margin (VM) distance of < 500 µm is a risk factor for recurrence in patients with T1 colorectal carcinoma (CRC) resected by endoscopy. We aimed to determine the effects of the VM distance on the recurrence and prognosis of T1 CRC. METHODS: We enrolled 168 patients with T1 CRC who underwent additional surgery after endoscopic submucosal dissection (ESD) at multiple centers between 2008 and 2016. None of the patients were followed up for < 5 years. The enrolled 168 patients were classified into patients with VM distance of < 500 µm including positive VM (n = 72 [43%], VM distance < 500 µm group) and patients with VM distance of ≥ 500 µm (n = 96 [57%], VM distance ≥ 500 µm group). The clinicopathological features, recurrence rates, and prognoses were compared between the groups using propensity-score matching (PSM). RESULTS: Tumors recurred in eight of the 168 patients (5%) with VM distance < 500 µm. After PSM, the rate of overall recurrence and local recurrence in the VM distance < 500 µm group were significantly higher than those in the VM distance ≥ 500 µm group. The 5-year recurrence-free survival rate was significantly higher in the VM distance ≥ 500 µm group than that in VM distance < 500 µm group after PSM (100% vs. 89%, p < 0.012). CONCLUSIONS: Complete en bloc resection of T1 CRC via ESD must include a sufficient amount of SM to reduce the risk of metastasis and recurrence after additional surgery.

Management of T1 Colorectal Cancer.

BACKGROUND: Approximately 10% of patients with submucosal invasive (T1) colorectal cancer (CRC) have lymph node metastasis (LNM). The risk of LNM can be stratified according to various histopathological factors, such as invasion depth, lymphovascular invasion, histological grade, and tumor budding. SUMMARY: T1 CRC with a low risk of LNM can be cured by local excision via endoscopic resection (ER), whereas surgical resection (SR) with lymph node dissection is required for high-risk T1 CRC. Current guidelines raise concern that many patients receive unnecessary SR, even though most patients achieve a radical cure. Novel diagnostic techniques for LNM, such as nomograms, artificial intelligence systems, and genomic analysis, have been recently developed to identify more low-risk T1 CRC cases. Assessing the curability and the necessity of additional treatment, including SR with lymph node dissection and chemoradiotherapy, according to histopathological findings of the specimens resected using ER, is becoming an acceptable strategy for T1 CRC, particularly for rectal cancer. Therefore, complete resection with negative vertical and horizontal margins is necessary for this strategy. Advanced ER methods for resecting the muscle layer or full thickness, which may guarantee complete resection with negative vertical margins, have been developed. KEY MESSAGE: Although a necessary SR should not be delayed for T1 CRC given its unfavorable prognosis when SR with lymph node dissection is performed, the optimal treatment method should be chosen based on the risk of LNM and the patient's life expectancy, physical condition, social characteristics, and wishes.

Urgent contrast-enhanced computed tomography before early colonoscopy in the management of colonic diverticular bleeding: A multicenter randomized controlled trial.

INTRODUCTION: Contrast-enhanced computed tomography (CE-CT) has been gaining attention as an initial investigation in the management of colonic diverticular bleeding (CDB), yet the role of CE-CT other than its diagnostic yield, has not been adequately clarified. We aimed to determine whether the use of urgent CE-CT improves identification of stigmata of recent hemorrhage (SRH) in subsequently performed early colonoscopy (≤24 hours of arrival) or other clinical outcomes of CDB. METHODS: We conducted a randomized, open-label, controlled trial at 23 institutions in Japan. Outpatients with suspected CDB were randomly assigned to undergo either urgent CE-CT followed by early colonoscopy (urgent-CE-CT + early-colonoscopy group) or early colonoscopy alone (early-colonoscopy group). The primary outcome was SRH identification. Secondary outcomes included successful endoscopic hemostasis, early (<30 days) and late (<1 year) rebleeding, length of hospital stay and transfusion requirements. RESULTS: In total, 240 patients, mostly in a hemodynamically stable condition, were randomized. A contrast extravasation on CE-CT was observed in 20 of 115 patients (17.4%) in the urgent-CE-CT + early-colonoscopy group. SRH was identified in 23 of 115 patients (20.0%) in the urgent-CE-CT + early-colonoscopy group and 21 of 118 patients (17.8%) in the early-colonoscopy group (difference, 2.2; 95% confidence interval [CI], -7.9 to 12.3; P=0.739). Successful endoscopic hemostasis was achieved in 21 patients in each group (18.3% and 17.8%, respectively) (difference, 0.5; 95% CI, -9.4 to 10.4; P=1.000). There were also no significant differences between groups in early and late rebleeding, length of hospital stay and transfusion requirements. CONCLUSION: The use of urgent CE-CT before early colonoscopy did not improve SRH identification or other clinical outcomes in patients with suspected CDB in a hemodynamically stable condition. The routine use of urgent CE-CT as an initial investigation is not recommended in this population, also considering the low rate of extravasation-positive cases (UMIN Registry number, UMIN000026865).

Nomogram as a novel predictive tool for lymph node metastasis in T1 colorectal cancer treated with endoscopic resection: a nationwide, multicenter study.

BACKGROUND AND AIMS: Since 2009, the Japanese Society for Cancer of the Colon and Rectum guidelines have recommended that tumor budding and submucosal invasion depth, in addition to lymphovascular invasion and tumor grade, be included as risk factors for lymph node metastasis (LNM) in patients with T1 colorectal cancer (CRC). In this study, a novel nomogram was developed and validated by usirge-scale, real-world data, including the Japanese Society for Cancer of the Colon and Rectum risk factors, to accurately evaluate the risk of LNM in T1 CRC. METHODS: Data from 4673 patients with T1 CRC treated at 27 high-volume institutions between 2009 and 2016 were analyzed for LNM risk. To prepare a nonrandom split sample, the total cohort was divided into development and validation cohorts. Pathologic findings were extracted from the medical records of each participating institution. The discrimination ability was measured by using the concordance index, and the variability in each prediction was evaluated by using calibration curves. RESULTS: Six independent risk factors for LNM, including submucosal invasion depth and tumor budding, were identified in the development cohort and entered into a nomogram. The concordance index was .784 for the clinical calculator in the development cohort and .790 in the validation cohort. The calibration curve approached the 45-degree diagonal in the validation cohort. CONCLUSIONS: This is the first nomogram to include submucosal invasion depth and tumor budding for use in routine pathologic diagnosis based on data from a nationwide multi-institutional study. This nomogram, developed with real-world data, should improve decision-making for an appropriate treatment strategy for T1 CRC.

A feasibility study comparing gel immersion endoscopic resection and underwater endoscopic mucosal resection for superficial nonampullary duodenal epithelial tumors.

BACKGROUND: Although gel immersion endoscopic resection (GIER) is a potential alternative to underwater endoscopic mucosal resection (UEMR) for superficial nonampullary duodenal epithelial tumors (SNADETs), comparisons between the two are currently insufficient. METHODS: 40 consecutive procedures performed in 35 patients were retrospectively reviewed; the primary outcome was procedure time, and the secondary outcomes were en bloc and R0 resection rates, tumor and specimen size, and adverse events. RESULTS: Lesions were divided into GIER (n = 22) and UEMR groups (n = 18). The median (range) procedure time was significantly shorter in the GIER group than in the UEMR group (2.75 [1-3.5] minutes vs. 3 2 3 4 5 6 7 8 9 10 minutes; P = 0.01). The en bloc resection rate was 100 % in the GIER group, but only 83.3 % in the UEMR group. The R0 resection rate was significantly higher in the GIER group than in the UEMR group (95.5 % vs. 66.7 %; P = 0.03). The median specimen size was larger in the GIER group than in the UEMR group (14 mm vs. 7.5 mm; P < 0.001). The tumor size was not significantly different between the groups and no adverse events were observed. CONCLUSIONS: GIER is efficacious and safe to treat SNADETs, although additional studies are needed.

Clinical features and images of malignant lymphoma localized in the pancreatic head to differentiate from pancreatic ductal adenocarcinoma: a case series study.

BACKGROUND: Pathological examination by endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) has been reported to be useful in diagnosing pancreatic malignant lymphoma (ML), but some ML cases are difficult to be differentiated from pancreatic ductal adenocarcinoma (PDAC). METHODS: This retrospective study included 8 patients diagnosed with ML that had a pancreatic-head lesion at initial diagnosis and 46 patients with resected PDAC in the pancreatic head between April 2006 and October 2021 at our institute. ML and PDAC were compared in terms of patients' clinical features and imaging examinations. RESULTS: The median tumor size was larger in ML than in PDAC (45.8 [24-64] vs. 23.9 [8-44] mm), but the median diameter of the caudal main pancreatic duct (MPD) was larger in PDAC (2.5 [1.0-3.5] vs. 7.1 [2.5-11.8] mm), both showing significant differences between these malignancies (both, P < 0.001). In the analysis of covariance, MLs showed a smaller caudal MPD per tumor size than PDACs, with a statistical difference (P = 0.042). Sensitivity and specificity using sIL-2R ≥ 658 U/mL plus CA19-9 < 37 U/mL for the differentiation of ML from PDAC were 80.0% and 95.6%, respectively. CONCLUSIONS: Diagnosing pancreatic ML using cytohistological examination through EUS-FNA can be difficult in some cases. Thus, ML should be suspected if a patient with a pancreatic tumor has a small MPD diameter per tumor size, high serum sIL-2R level, normal CA19-9 level. If the abovementioned features are present and still cannot be confirmed as PDAC, re-examination should be considered.

Endoscopic submucosal dissection for tumors involving the ileocecal valve with extension into the terminal ileum: a multicenter study from the Hiroshima GI Endoscopy Research Group.

BACKGROUND: The efficacy and safety of endoscopic submucosal dissection (ESD) for tumors extending into the terminal ileum remain obscure. We aimed to evaluate the outcomes of ESD for tumors involving the ileocecal valve (ICV) with extension into the terminal ileum. METHODS: Sixty-eight patients (40 men; mean age, 67 years) with 68 tumors involving the ICV that were resected by ESD between December 2013 and December 2018 were included and classified into Group A (21 tumors with extension into the terminal ileum) and Group B (47 tumors without extension). ESD outcomes were compared between groups. RESULTS: The clinical features of the patients and tumors were not significantly different between the groups. There were no significant differences in en bloc resection rate (95% and 94%, respectively; p = 0.79), R0 resection rate (90% and 89%, respectively; p = 0.89), procedure time (95 ± 54 min and 94 ± 69 min, respectively; p = 0.64), postoperative bleeding rate (5% and 3%, respectively; p = 0.79), intraoperative perforation rate (0% and 4%, respectively; p = 0.34), delayed perforation rate (0% and 0%, respectively), or postoperative symptomatic stenosis rate (0% and 0%, respectively) between Groups A and B. No specific factors related to the outcomes of ESD were found by subgroup analysis according to the dominance and degree of circumference of the ICV. Local recurrence was observed in 1 patient in Group A who was retreated using ESD. CONCLUSIONS: ESD for tumors involving the ICV with extension into the terminal ileum is safe and effective.

Efficacy of a Traction Device for Endoscopic Submucosal Dissection Using a Scissor-Type Knife: A Randomized Controlled Trial.

INTRODUCTION: Although safe, colorectal endoscopic submucosal dissection (ESD) using a scissor-type knife has a slow resection speed. We aimed to evaluate the efficacy of a traction device to hasten the resection speed. METHODS: This multicenter randomized controlled trial was conducted at 3 Japanese institutions. Patients with a 20-50-mm superficial colorectal tumor were enrolled and randomly assigned to a conventional-ESD (C-ESD) group or a traction-assisted ESD (T-ESD) group. The primary outcome was the resection speed. RESULTS: The C-ESD and T-ESD groups comprised 49 and 48 patients, respectively. Although the mean resection speed was not significantly different in the entire cohort between the groups (23.7 vs 25.6 mm 2 /min, respectively; P = 0.43), it was significantly faster with T-ESD than with C-ESD at the cecum (32.4 vs 16.7 mm 2 /min, respectively; P = 0.02). The mean resection speed of tumors ≥30 mm tended to be faster by T-ESD than by C-ESD (34.6 vs 27.8 mm 2 /min, respectively; P = 0.054). The mean procedure time of T-ESD was significantly shorter than that of C-ESD (47.3 vs 62.3 minutes, respectively; P = 0.03). The en bloc (100% vs 100%), complete (98.0% vs 97.9%), and curative resection (93.9% vs 91.7%) rates were similar between the 2 groups. Perforation and delayed hemorrhage occurred in only 1 patient each in the T-ESD group. DISCUSSION: Although the resection rates were sufficiently high and adverse event rates were extremely low in both the groups, the use of a traction device for ESD in the proximal colon and for large lesions may increase the resection speed.

Efficacy and safety comparison of scissor-type knives with needle-type knives for colorectal endoscopic submucosal dissection: a post-hoc propensity score-matched analysis (with videos).

BACKGROUND AND AIMS: Many knives have been developed to improve the efficacy and safety of endoscopic submucosal dissection (ESD). We aimed to evaluate the efficacy and safety of scissor-type knives for colorectal ESD compared with needle-type knives. METHODS: We performed a post-hoc propensity score-matched analysis in an 11-facility study between August 2013 and December 2018. A total of 2330 patients (2498 lesions) who underwent colorectal ESD were divided into needle-type (1923 patients, 2067 lesions) and scissor-type (407 patients, 431 lesions) knife groups. Short-term outcomes were compared between the 2 groups. RESULTS: Two-to-one propensity score-matched analysis identified 814 (709 patients) and 407 (386 patients) lesions in the needle- and scissor-type knife groups, respectively. The median resection speed was significantly faster in the needle-type group (18.3 mm2/min) than in the scissor-type group (13.2 mm2/min, P < .0001), whereas en-bloc and histologic complete resection rates were not significantly different between the needle- and scissor-type groups (96.8% [788/814] vs 98.3% [400/407], P = .1888 and 95.1% [774/814] vs 95.6% [389/407], P = .7763, respectively). The rate of lesions resected using a single knife was significantly higher in the scissor-type group (98.5% [401/407]) than in the needle-type group (43.9% [357/814], P < .0001). Rates of intraoperative perforation and delayed bleeding were significantly lower in the scissor-type group than in the needle-type group (.7% [3/407] vs 2.5% [20/814], P = .0431 for each). CONCLUSIONS: Scissor-type knives are safer for colorectal ESD. However, they are associated with slower resection speeds compared with needle-type knives. (Clinical trial registration number: UMIN000016197.).

Long-standing diabetes mellitus increases concomitant pancreatic cancer risk in patients with intraductal papillary mucinous neoplasms.

BACKGROUND: When monitoring patients with an intraductal papillary mucinous neoplasm (IPMN), it is important to consider both IPMN-derived carcinoma and concomitant ductal adenocarcinoma (PDAC). The latter is thought to have a poorer prognosis. We retrospectively analyzed the risk factors for concomitant PDAC in IPMN. METHODS: In total, 547 patients with pancreatic cysts, including IPMNs inappropriate for surgery on initial diagnosis, encountered from April 2005 to June 2019, were reviewed. We performed surveillance by imaging examination once or twice a year. RESULTS: Five IPMNs with high-grade dysplasia and one IPMN associated with invasive carcinoma were encountered. In comparison, 14 concomitant PDACs were encountered. The prognosis was very poor for concomitant PDACs. All 14 PDAC patients had IPMNs. In patients with IPMNs, long-standing diabetes mellitus was the only significant risk factor for concomitant PDAC in both univariate and multivariate analyses (P < 0.001 and P < 0.01, respectively). Furthermore, patients with IPMNs and diabetes mellitus had a high frequency of concomitant PDACs (9.5%, 9/95) in a median 48-month surveillance period. CONCLUSIONS: When monitoring IPMNs, the development of not only IPMN-derived carcinomas but also concomitant PDACs should be considered. During this period, it may be prudent to concentrate on patients with other risk factors for PDAC, such as long-standing diabetes mellitus.

Factors for conversion risk of colorectal endoscopic submucosal dissection: a multicenter study.

BACKGROUND: Endoscopic submucosal dissection (ESD) has become a widely accepted treatment method for colorectal tumors; however, there are some persistent problems. This multi-center study aimed to characterize the risk factors for incomplete resection and perforation in standardized colorectal ESD procedures. METHODS: This study included 2423 consecutive patients who underwent ESD for 2592 colorectal tumors between August 2013 and December 2018 at 11 institutions (1 academic hospital and 10 affiliated hospitals) from the Hiroshima GI Endoscopy Research Group. We evaluated the risk factors for interruption, piecemeal resection, and perforation of standardized colorectal ESD in relation to clinicopathologic and endoscopic characteristics. RESULTS: The incidences of interruption, piecemeal resection, and perforation were 0.7%, 2.9%, and 3.0%, respectively. Multivariate analysis identified the following risk factors for interruption: perforation during the procedure, deep submucosal invasion (> 1000 µm), poor scope operability, and severe submucosal fibrosis. The risk factors for piecemeal resection included poor scope operability, severe submucosal fibrosis, and procedure time (≥ 85 min). The risk factors for perforation during the procedure were severe submucosal fibrosis, poor scope operability, procedure time (≥ 85 min), and tumor size (≥ 40 mm). Independent risk factors for severe submucosal fibrosis included a history of biopsy and lesions located on the fold or flexure. CONCLUSIONS: Severe submucosal fibrosis and poor scope operability are the common risk factors for interruption, piecemeal resection, and perforation in standardized colorectal ESD.

Indications and outcomes of colorectal hybrid endoscopic submucosal dissection: a large multicenter 10-year study.

BACKGROUND AND AIMS: Hybrid endoscopic submucosal dissection (ESD) is a colorectal lesion resection procedure that includes both planned and salvage procedures. Previous colorectal hybrid ESD studies have involved single institutions or few operators over a short timeframe, and the size for indication has not been established. In this multicentre study, we investigated the clinical outcomes of hybrid ESD for colorectal tumors that met the 30 mm lesion size criterion. METHODS: From January 2008 to December 2018, colorectal hybrid ESD was performed for 172 lesions (diameter range, ≥ 20- < 30 mm) at Hiroshima GI Endoscopy Research Group. We compared clinicopathological characteristics and outcomes between 56 and 116 lesions in planned and salvage groups, respectively. We also compared data between 2008 and 2013 (the first period) and 2014 and 2018 (the second period) to assess operator experience. RESULTS: No significant difference was found in the complete en bloc resection rate between the planned and salvage groups (92.9% vs. 83.6%, respectively). Procedure time was shorter in the planned group (44.5 min) than in the salvage group (72.0 min, p < 0.01). The perforation rate was higher in the salvage group (21.6%) than in the planned group (0%, p < 0.01); however, the perforation rate during snaring in the salvage group was 1.8%. During the second period relative to the first period, we recorded a significantly higher complete en bloc resection rate (95.7% vs. 75.6%, respectively, p < 0.01) and experienced operator rate (75.5% vs. 53.9%, respectively, p < 0.01). Furthermore, no significant difference was found in the complete en bloc resection rate between the planned and salvage groups during the second period (100% vs. 94.4%, respectively). CONCLUSION: Colorectal hybrid ESD, especially salvage hybrid ESD performed by experienced operators, is adoptable and safe for lesions with diameters ranging from ≥ 20 to < 30 mm.

Long-term outcomes of standardized colonic stenting using WallFlex as a bridge to surgery: Multicenter prospective cohort study.

OBJECTIVES: The oncological outcomes, especially high recurrence rate, of bridge-to-surgery (BTS) self-expandable metallic stent (SEMS) placement remain concerning, emphasizing the necessity of standardized SEMS placement. However, its impact on long-term BTS outcomes is unknown. We investigated the long-term outcomes of BTS colonic stenting using standardized SEMS placement. METHODS: This prospective, multicenter cohort study conducted at 46 hospitals in Japan (March 2012 to October 2013) included consecutive patients with stage II and III obstructive colorectal cancer managed with BTS SEMS placement. The SEMS placement technique was standardized by information dissemination among the participating hospitals. The primary outcome was overall survival (OS) after SEMS placement, and the secondary outcomes were relapse-free survival (RFS), recurrence, and short-term outcomes of SEMS placement and surgery. RESULTS: The 1-, 3-, and 5-year OS rates were 94.1%, 77.4%, and 67.4% (Kaplan-Meier), respectively, with high technical success (99.0%, 206/208) and low perforation (1.9%, 4/208) rates. The 1-, 3-, and 5-year RFS rates were 81.6%, 65.6%, and 57.9% (Kaplan-Meier), respectively, and the overall recurrence rate was 31.0% (62/200). The RFS rate was significantly poorer in patients with perforation (n = 4) than in those without perforation (n = 196) (log-rank P = 0.017); moreover, perforation was identified as an independent factor affecting RFS (hazard ratio 3.31; 95% confidence interval 1.03-10.71, multivariate Cox regression). CONCLUSION: This large, prospective, multicenter study revealed satisfactory long-term outcomes of BTS colonic stenting using a standardized SEMS insertion method, which might be specifically due to the reduced perforation rate. (UMIN000007953).

Water-assisted colonoscopy: an international modified Delphi review on definitions and practice recommendations.

BACKGROUND AND AIMS: Since 2008, a plethora of research studies has compared the efficacy of water-assisted (aided) colonoscopy (WAC) and underwater resection (UWR) of colorectal lesions with standard colonoscopy. We reviewed and graded the research evidence with potential clinical application. We conducted a modified Delphi consensus among experienced colonoscopists on definitions and practice of water immersion (WI), water exchange (WE), and UWR. METHODS: Major databases were searched to obtain research reports that could potentially shape clinical practice related to WAC and UWR. Pertinent references were graded (Grading of Recommendations, Assessment, Development and Evaluation). Extracted data supporting evidence-based statements were tabulated and provided to respondents. We received responses from 55 (85% surveyed) experienced colonoscopists (37 experts and 18 nonexperts in WAC) from 16 countries in 3 rounds. Voting was conducted anonymously in the second and third round, with ≥80% agreement defined as consensus. We aimed to obtain consensus in all statements. RESULTS: In the first and the second modified Delphi rounds, 20 proposed statements were decreased to 14 and then 11 statements. After the third round, the combined responses from all respondents depicted the consensus in 11 statements (S): definitions of WI (S1) and WE (S2), procedural features (S3-S5), impact on bowel cleanliness (S6), adenoma detection (S7), pain score (S8), and UWR (S9-S11). CONCLUSIONS: The most important consensus statements are that WI and WE are not the same in implementation and outcomes. Because studies that could potentially shape clinical practice of WAC and UWR were chosen for review, this modified Delphi consensus supports recommendations for the use of WAC in clinical practice.

The efficacy of prophylactic clip closure of mucosal defects after colorectal endoscopic submucosal dissection on delayed bleeding.

OBJECTIVE: Although prophylactic clip closure after endoscopic mucosal resection may prevent delayed bleeding, information regarding colorectal endoscopic submucosal dissection (CR-ESD) is lacking. Therefore, this study evaluated the effect of prophylactic clip closure on delayed bleeding rate after CR-ESD. MATERIALS AND METHODS: A total of 614 CR-ESD procedures performed in 561 patients were retrospectively reviewed. The primary outcome, which was delayed bleeding rate, was analyzed between the prophylactic clip closure and non-closure groups. Furthermore, the predictors of delayed bleeding were also evaluated. RESULTS: The patients were divided into the clip closure group (n = 275) and non-closure group (n = 339). Delayed bleeding rate was significantly lower in the closure group than in non-closure group (6 cases [2.2%] vs. 20 cases [5.9%], p = .026). The univariate logistic regression analyses revealed that delayed bleeding was significantly associated with laterally spreading tumor-granular-nodular mixed type (LST-G-Mix; odds ratio [OR], 3.77; 95% confidence interval [CI], 1.70-8.34; p = .001). By contrast, prophylactic clip closure was significantly associated with low delayed bleeding rate (OR, 0.36; 95%CI, 0.14-0.90; p = .029). The multivariate logistic regression analyses revealed LST-G-Mix as a significant independent delayed bleeding predictor (OR, 3.25; 95%CI, 1.45-7.32; p = .004), whereas, prophylactic clip closure was identified as a significant independent preventive factor of delayed bleeding (OR, 0.39; 95%CI, 0.15-1.00; p = .049). CONCLUSIONS: Prophylactic clip closure after CR-ESD is associated with low delayed bleeding rate. LST-G-Mix promotes delayed bleeding, and performing prophylactic clip closure may be advisable.

Endoscopic resection of local recurrences of diminutive polyps by cold forceps polypectomy.

OBJECTIVES: Cold forceps polypectomy (CFP) is an effective treatment for diminutive colorectal polyps. However, polyps occasionally recur, and there is no consensus on their long-term clinical management. Therefore, we investigated the short- and long-term clinical outcomes of re-CFP for recurrent diminutive colorectal polyps. MATERIALS AND METHODS: This was a follow-up of a multicenter, prospective study investigating the clinical outcomes of diminutive colorectal polyps excised by CFP with narrowband imaging-enhanced endoscopy and jumbo forceps. We evaluated short-term outcomes of re-CFP and patients at 1-year follow-up post re-CFP for recurrent colorectal polyps to determine long-term recurrence rates. Additionally, complete resection rates, clinicopathological features, number of forceps bites, and rate of short-term adverse events managed by re-CFP were evaluated. RESULTS: At 1-year follow-up, local recurrence was identified in 18 patients from the original study. The mean size of local recurrent polyps was 1.5 ± 0.6 mm, and all recurrent lesions were < 3 mm. Re-CFP could successfully excise locally recurrent polyps in all cases. All recurrent lesions were low-grade adenomas; no adverse events were reported. Additionally, 16 of 18 patients were evaluated endoscopically at 2-year follow-up; no recurrence was observed. CONCLUSIONS: Recurrent lesions following initial CFP were small and pathologically benign, and re-CFP was an effective treatment.

A case of intraductal tubulopapillary neoplasm of the pancreas in a branch duct: a rare case report and literature review.

BACKGROUND: Intraductal tubulopapillary neoplasm (ITPN) of the pancreas is a new disease concept defined by the World Health Organization in 2010. ITPN progresses with tubulopapillary growth in the pancreatic duct and is known to have a fair prognosis. Localization in the main pancreatic duct (MPD) is one characteristic. There are few case reports of ITPN in a branch of the pancreatic duct (BD). CASE PRESENTATION: We encountered a case of ITPN localized in BD. An 85-year-old man was followed after colonic surgery for rectal carcinoma. An abdominal computed tomography scan revealed a cystic mass in the pancreatic head and further examination was done. A T2 weighted intension picture in magnetic resonance imaging showed a 20 mm cystic lesion with an internal mass of 15 mm. Duodenal papilla were slightly open and endoscopic retrograde pancreatography revealed mild and diffuse dilatation of the main pancreatic duct and mucin in the MPD. In consideration with the image examinations, we diagnosed the tumor as an intraductal papillary mucinous neoplasm with carcinoma because of its large mural nodule (> 10 mm in size) in a cyst. Consequently, a pancreaticoduodenectomy was performed. Macroscopically, a white solid tumor sized 2.5 × 1.8 × 1.0 was identified in the head of the pancreas. The cut surface of the resected pancreas showed a side-branch type intraductal tumor with tubulopapillary architecture without mucin secretion. Immunohistochemical staining was positive for MUC1, and negative for MUC2 and MUC5AC. The final diagnosis was determined to be pancreatic ITPN from BD. At the time of this report (48 months post-surgery), the patient remains disease-free without evidence of recurrence. CONCLUSION: ITPNs localized in BD are rare and diagnosis prior to surgery is difficult. In our case, the shape was round, not papillary, and with little fluid. These characteristics are different from a branch duct type IPMN and can be a clue to suspect ITPN in BD.