CO2 enterography in endoscopic retrograde cholangiography using double-balloon endoscopy: A randomized clinical trial.

BACKGROUND AND AIM: Double-balloon endoscopic retrograde cholangiography (DBERC) is a valuable procedure for patients with altered gastrointestinal anatomy. Nonetheless, it is time-consuming and burdensome for both patients and endoscopists, partly because route selection in the reconstructed bowel with complicating loop is challenging. Carbon dioxide insufflation enterography is reportedly useful for route selection in the blind loop. This prospective randomized clinical trial investigated the usefulness of carbon dioxide insufflation enterography for route selection by comparing it with conventional observation. METHODS: Patients scheduled to undergo DBERC were consecutively registered. They were divided into carbon dioxide insufflation enterography and conventional groups via randomization according to stratification factors, type of reconstruction methods, and experience with DBERC. The primary endpoint was the correct rate of initial route selection. The secondary endpoints were the insertion time, examination time, amount of anesthesia drugs, and complications. RESULTS: The correct rate of route selection was significantly higher in the carbon dioxide insufflation enterography group (23/25, 92%) than in the visual method (15/25, 60%) (P = 0.018). The insertion time was significantly shorter in the carbon dioxide insufflation enterography group than in the visual group (10.8 ± 11.1 min vs 29.8 ± 15.7 min; P < 0.001). No significant differences in complications were noted between the two groups. The amounts of sedatives and analgesics used were significantly lower in the carbon dioxide insufflation enterography group (P < 0.001 and P < 0.001, respectively). CONCLUSIONS: Carbon dioxide insufflation enterography can reduce the burden of DBERC on patients and endoscopists by shortening the examination time and reducing the amount of medication.

Factors associated with inaccurate size estimation of colorectal polyps: A multicenter cross-sectional study.

BACKGROUND AND AIM: Accurate polyp size estimation is essential in deciding the therapeutic strategy of colorectal polyps and endoscopic surveillance intervals. However, many endoscopists frequently make incorrect size estimations without being aware of their errors. This cross-sectional study aimed to clarify the characteristics of endoscopists associated with inaccurate estimation. METHODS: We previously conducted a web trial involving 261 endoscopists in 51 institutions in Japan to assess their ability to estimate polyp size. Participants answered questions about polyp size using visual estimates in a test involving images of 30 polyps. Here, we investigated the relationships between inaccurate size estimation and the backgrounds of participants. The rates of overestimation and underestimation of polyp size were also compared to clarify any trends in the answers of participants with low accuracy (< 50%). RESULTS: Multivariable logistic regression analysis revealed that the number of colonoscopic procedures in the past year was the only factor associated with a low accuracy of polyp size estimation (odds ratio 0.750, 95% confidence interval 0.609-0.925; P = 0.007). Endoscopists with low accuracy had a greater tendency to overestimate polyp size (42.3% overestimation and 21.2% underestimation, P < 0.001) compared with other endoscopists (16.6% overestimation and 17.9% underestimation, P = 0.951). CONCLUSIONS: Endoscopists with limited experience of colonoscopy in the past year were more likely to make frequent errors in size estimation. Furthermore, endoscopists making inaccurate size estimations had a propensity to overestimate polyp size.

A forward-viewing radial-array echoendoscope is useful for diagnosing the depth of colorectal neoplasia invasion.

BACKGROUND: It is important to accurately diagnose the depth of colorectal neoplasia invasion. We aimed to evaluate the usefulness of a new forward-viewing radial-array echoendoscope (FRE), relative to the pit pattern method. METHODS: In this prospective study, the invasion depth of suspected early-stage carcinoma was diagnosed using the pit pattern and FRE methods. The diagnoses were classified as T1a (submucosal invasion distance < 1,000 µm) or shallower and T1b (≥ 1,000 µm) or deeper. Pathological diagnoses were used to compare the diagnostic capabilities of the two methods. RESULTS: The final analyses included 110 lesions. The FRE was successfully inserted to the lesion in all cases. There were no significant differences between the two methods regarding the correct prediction rate (79.1% vs. 75.5%, P = 0.57), accuracy (81.3% vs. 79.0%, P = 0.68), specificity (81.3% vs. 70.8%, P = 0.135), positive predictive value (65.0% vs. 60.4%, P = 0.649), negative predictive value (91.0% vs. 98.1%, P = 0.108), or frequency of unevaluable cases (2.7% vs. 4.5%, P = 0.471). The correct prediction rate was calculated by adding the number of unevaluable cases to the denominator of accuracy. Relative to the pit pattern method, the FRE method offered significantly higher sensitivity for predicting T1b or deeper invasion (81.3% vs. 97.0%, P = 0.048). The pit pattern method had significantly poorer accuracy for large lesions (> 36 mm) than for smaller lesions (≤ 36 mm). In contrast, the accuracy of the FRE method did not differ significantly with lesion size. When using the FRE method, no cases were unevaluable because of attenuation. The FRE method provided correct diagnoses in 2 of 3 cases that were unevaluable using the pit pattern method. CONCLUSIONS: The pit pattern and FRE methods offered similar diagnostic performance for invasion depth. Furthermore, the FRE method may be used to correctly diagnose cases that are unevaluable using the pit pattern method.

Endoscopic Ultrasound Elastography as a Novel Diagnostic Method for the Assessment of Hardness and Depth of Invasion in Colorectal Neoplasms.

INTRODUCTION: We aimed to compare the efficacy of endoscopic ultrasound elastography (EUS-EG) with that of magnifying chromoendoscopy (MCE) and endoscopic ultrasonography (EUS) for the diagnosis of the depth of invasion in colorectal neoplasms. This is an important clinical issue as the depth of invasion is associated with the risk of metastasis. METHODS: Consecutive patients with suspected superficial colorectal neoplasms, evaluated by MCE, EUS, and EUS-EG, for whom endoscopic submucosal dissection was considered, were enrolled in 2018 (derivation study) and in 2019-2020 (validation study). The primary clinical endpoint was the diagnostic yield differentiating intramucosal and shallow submucosal neoplasms from deep submucosal (dSM) and advanced colorectal cancers. In addition, inter- and intra-observer agreements of the elastic score of colorectal neoplasm (ES-CRN) were evaluated by 2 expert and 2 non-expert endoscopists. RESULTS: Thirty-one (33 lesions) and 50 (55 lesions) patients were enrolled in the derivation and validation studies, respectively. Sensitivity, specificity, positive, and negative predictive values, and accuracy of assessment of the depth of submucosal or deeper invasion in the derivation and validation groups were as follows: EUS-EG, 100/88.2/86.7/100/93.3% and 77.8/86.1/73.7/88.6/83.3%; MCE, 66.7/94.4/90.9/77.3/81.8% and 84.2/91.4/84.2/91.4/88.9%; and EUS, 93.3/77.8/77.8/93.3/84.8% and 89.5/65.7/58.6/92.0/74.1%, respectively. For the 2 expert endoscopists, interobserver agreement for the ES-CRN (first and second assessments) in the derivation group was 0.84 and 0.78, respectively; these values were 0.73 and 0.49, respectively, for the 2 non-expert endoscopists. DISCUSSION/CONCLUSION: All 3 modalities presented similar diagnostic yield. Inter- and intra-observer agreements of the ES-CRN were substantial, even for non-expert endoscopists. Therefore, EUS-EG may be a useful modality in determining the depth of invasion in colorectal neoplasms.

New modality for the quantitative evaluation of tissue elasticity using a forward-viewing radial-array echoendoscope for colorectal neoplasms.

PURPOSE: Sound speed correction (SSC) is a non-invasive modality that quantifies the hardness of neoplasms. The aim of our study was to evaluate the usefulness of SSC for the diagnostic accuracy of colorectal neoplasms and to differentiate the depth of invasion. METHODS: Forty colorectal neoplasms, contributed by 40 patients, were included in the analysis. The primary outcome was the diagnostic ability of SSC for the depth of invasion of colorectal neoplasms, with the secondary endpoint being the clinical efficacy of SSC to distinguish between a neoplasm and normal mucosa. RESULTS: The median sound speeds for colorectal neoplasms and normal mucosa were 1580 m/s and 1515 m/s, respectively (p < 0.001), with a median sound speed of 1583 m/s for lesions with a depth shallower than that of the muscularis propria and 1610 m/s for depths deeper than that of the muscularis propria (p = 0.002). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 80.0%, 100%, 100%, 83.3%, 90.0%, and 100%, respectively, for the diagnosis of neoplasms (using a cut-off sound speed of 1557 m/s) and 100%, 77.8%, 33.3%, 100%, 80.0%, respectively, for the diagnosis of the depth of invasion (using a cut-off of 1590 m/s). CONCLUSION: We identified absolute sound speeds for colorectal neoplasms and the depth of invasion of neoplasms which yielded a good diagnostic performance. SSC provides an objective evaluation of colorectal neoplasms and the depth of invasion of neoplasms and, thus, might be a useful modality in practice. TRIAL REGISTRATION: UMIN000038235 , Date of registration; October 8, 2019.

Learning curve for mastery of colorectal endoscopic submucosal dissection: Perspectives from a large Japanese cohort.

BACKGROUND AND AIM: Endoscopic submucosal dissection (ESD) is a challenging procedure. A dissection speed of ≥9 cm2/h has been acknowledged as a mark for expertise, alongside a complication rate of ≤5% and en bloc resection rate of ≥90%. However, there is lack of objective information on whether the three measures correlate with each other. This study aims to evaluate the dissection speed, safety, and efficacy of colorectal ESDs performed by experts and trainees. METHODS: Consecutive patients undergoing colorectal ESD at a Japanese hospital (2006-2017) were included in a prospectively collected database. Information on patient demographics, proceduralist, and intra-/postprocedure data was retrieved. The primary outcome was the comparison in dissection speed. The secondary outcomes included differences in safety and efficacy. Log-linear regression models adjusted for confounders (e.g. R0 resection) were used to assess the differences in dissection speed. RESULTS: Five hundred ninety procedures (514 patients) performed by 26 endoscopists were analyzed. Experts performed a higher number of difficult lesions (e.g. F2 fibrosis) but achieved higher dissection speed (10.3 vs 6.7 cm2/h). The difference was statistically significant for both unadjusted and adjusted models (P < 0.0001). The en bloc resection rates were similar for both groups (experts = 95.6%; trainees = 94.7%, P = 0.61). Although nonexperts damaged more of the muscularis propria (18.6 vs 12.5%, P = 0.04), this did not translate into a significant difference in perforation (experts = 3.7%; trainees = 6.9%, P = 0.09) or delayed bleeding (experts = 2.9%; trainees = 4.4%, P = 0.34). The dissection speed steadily increased with expertise. CONCLUSION: Although dissection speed for colorectal ESD was significantly higher for experts, ESDs could be safely and efficaciously performed by ESD trainees.

Magnetic anchor-guided endoscopic submucosal dissection for gastric lesions (with video).

BACKGROUND AND AIMS: The feasibility of magnetic anchor-guided endoscopic submucosal dissection (MAG-ESD) using a neodymium magnet for gastric lesions has not been clarified. The aim of study was to evaluate the feasibility of MAG-ESD using neodymium magnets while treating gastric lesions. METHODS: This prospective trial was conducted at the Yamashita Hospital. MAG-ESD was performed for 50 gastric lesions using an insulated-tip knife. The magnetic anchor consisted of an internal neodymium magnet attached to a hemoclip with 3-0 silk. The external and internal magnets were made from the neodymium magnet. The feasibility of traction using MAG-ESD, en bloc resection rate, complete en bloc resection rate, time required for preparation and attaching the magnetic anchor, procedure time, rate of retrieval of the magnetic anchors, and adverse events were evaluated. RESULTS: Fifty patients (median lesion size, 20 mm [range, 5-100]) were enrolled. MAG-ESDs were successfully performed for all 50 gastric lesions. Adequate counter-traction was obtained using the external magnet. En bloc resections were achieved and complete en bloc resections confirmed in all cases without adverse events. Attaching the magnetic anchor required a median of 6 minutes (range, 2-14). The median procedure time was 49 minutes (range, 15-301), and the magnetic anchors could be retrieved in all cases. CONCLUSIONS: This study clearly demonstrated the feasibility of this MAG-ESD in the stomach. We hope this procedure will facilitate the resection of difficult lesions. (Clinical trial registration number: UMIN000024100.).

Concurrent chemoradiotherapy with a novel fluoropyrimidine, S-1, and cisplatin for locally advanced esophageal cancer: long-term results of a phase II trial.

OBJECTIVES: A phase II study was performed to investigate the safety and efficacy of concurrent chemoradiotherapy (CCRT) combined with an orally active fluoropyrimidine, S-1, plus cisplatin for locally advanced esophageal cancer (LAEC). METHODS: CCRT comprised 2 courses, a 30-Gy radiotherapy over 3 weeks plus daily oral S-1 (80 mg/m(2)/day) for 2 weeks and a 24-hour cisplatin infusion (70 mg/m(2)) on day 8, and an identical course administered after a 2-week break. RESULTS: One hundred and sixteen patients, 12 with stage II, 71 with stage III, and 33 with stage IVa LAEC participated, and 106 of them (91.4%) completed the CCRT course. The most serious toxicity was myelosuppression: grade 3 and 4 neutropenia occurred in 28.4 and 9.5% of patients, respectively. Nonhematologic toxicity was moderate. Complete response rates in patients with stage II, III, and IVa LAEC were 91.7, 67.6, and 36.4%, respectively. The overall median survival time was 2.3 years and that of patients with stage II, III, and IVa cancer was 7.0, 2.6, and 1.3 years, respectively. CONCLUSIONS: CCRT combined with S-1 plus cisplatin showed promising safety and efficacy. Potentially, this combination therapy could become a baseline medication for patients with LAEC.