Endoscopic Ultrasound Can Differentiate High-Grade Pancreatic Intraepithelial Neoplasia, Small Pancreatic Ductal Adenocarcinoma, and Benign Stenosis.

Background/Aims: High-grade pancreatic intraepithelial neoplasia and invasive pancreatic ductal adenocarcinoma ≤10 mm are targets for early detection of pancreatic cancer. However, their imaging characteristics are unknown. We aimed to identify endoscopic ultrasound findings for the detection of these lesions. Methods: Patients diagnosed with high-grade pancreatic intraepithelial neoplasia (n=29), pancreatic ductal adenocarcinoma ≤10 mm (n=11) (who underwent surgical resection), or benign main pancreatic duct stenosis (n=20) between January 2014 and January 2021 were retrospectively included. Six features differentiating these lesions were examined by endoscopic ultrasonography: main pancreatic duct stenosis, upstream main pancreatic duct dilation, hypoechoic areas surrounding the main pancreatic duct irregularities (mottled areas without demarcation or round areas with demarcation), branch duct dilation, prominent lobular segmentation, and atrophy. Interobserver agreement was assessed by two independent observers. Results: Hypoechoic areas surrounding the main pancreatic duct irregularities were observed more frequently in high-grade pancreatic intraepithelial neoplasia (82.8%) and pancreatic ductal adenocarcinoma ≤10 mm (90.9%) than in benign stenosis (15.0%) (p<0.001). High-grade pancreatic intraepithelial neoplasia exhibited mottled hypoechoic areas more frequently (79.3% vs 18.9%, p<0.001), and round hypoechoic areas less frequently (3.4% vs 72.7%, p<0.001), than pancreatic ductal adenocarcinoma ≤10 mm. The sensitivity and specificity of hypoechoic areas for differentiating high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis were both 85.0%, with moderate interobserver agreement. Conclusions: The hypoechoic areas surrounding main pancreatic duct irregularities on endoscopic ultrasound may differentiate between high-grade pancreatic intraepithelial neoplasia, pancreatic ductal adenocarcinoma ≤10 mm, and benign stenosis (Trial Registration: UMIN Clinical Trials Registry (UMIN000044789).

Adenosquamous carcinoma coexisting with intraductal papillary mucinous neoplasm of the pancreas: a case report.

BACKGROUND: Adenosquamous carcinoma of the pancreas is a rare variant, with a worse prognosis than pancreatic ductal adenocarcinoma; moreover, it has characteristic clinical and histopathological features. Studies have mentioned the differentiation of intraductal papillary mucinous neoplasms into mucinous/tubular adenocarcinomas; however, their transdifferentiation into adenosquamous carcinoma remains unclear. CASE PRESENTATION: An 80-year-old Japanese woman was referred to our hospital for further examination of multiple pancreatic cysts. Enhanced computed tomography after close follow-up for 6 years revealed a new nodule with poor enhancement on the pancreatic body. Distal pancreatectomy and splenectomy were performed. Histopathological examination revealed an adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms; moreover, the intraductal papillary mucinous neoplasms lacked continuity with the adenosquamous carcinoma. Immunohistochemical analysis revealed squamous cell carcinoma and differentiation from adenocarcinoma to squamous cell carcinoma. Gene mutation analysis revealed KRASG12D and KRASG12R mutations in adenosquamous carcinoma components and intraductal papillary mucinous neoplasm lesions, respectively, with none showing the mutation of GNAS codon 201. The final histopathological diagnosis was adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms of the pancreas. CONCLUSIONS: This is the rare case of adenosquamous carcinoma with coexisting intraductal papillary mucinous neoplasms of the pancreas. To investigate the underlying transdifferentiation pathway of intraductal papillary mucinous neoplasms into this rare subtype of pancreatic cancer, we explored gene mutation differences as a clinicopathological parameter.

Treatment Outcome of Nab-paclitaxel Plus Gemcitabine for Leptomeningeal Carcinomatosis from Pancreatic Ductal Adenocarcinoma: An Autopsy Case Report.

A 57-year-old woman with a sudden-onset seizure was hospitalized. Brain magnetic resonance imaging findings led to a suspicion of leptomeningeal carcinomatosis (LMC) without a brain parenchymal tumor, and abdominal computed tomography showed a tumor in the pancreatic tail. Endoscopic ultrasonography-guided fine needle aspiration of the pancreatic mass revealed adenocarcinoma. Therefore, LMC from pancreatic ductal adenocarcinoma was strongly suspected. She received three courses of nab-paclitaxel plus gemcitabine and whole-brain radiation. Shortly thereafter, she developed a severe consciousness impediment and died. A pathological autopsy showed adenocarcinoma in a wide area of the leptomeninges.

[Use of EUS-FNA in the diagnosis of hilar schwannoma:a case report].

Upon abdominal ultrasonography, a woman in her 36 years old was diagnosed with a hypoechoic tumor with a diameter of 60mm surrounding the bile duct in the hepatic portal region. Abdominal computed tomography and magnetic resonance cholangiopancreatography revealed a tumor-like mass in the bile duct. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) confirmed the diagnosis of schwannoma. Considering the lesion location, it appeared to rise from the hepatoduodenal ligament. She was unwilling to undergo tumor resection;however, a year after the diagnosis, no change was observed in the tumor. Here, we report a case of schwannoma in the hepatoduodenal ligament, wherein EUS-FNA was useful for establishing a diagnosis and determining a treatment strategy.

A novel sensitive detection method for DNA methylation in circulating free DNA of pancreatic cancer.

Despite recent advances in clinical treatment, pancreatic cancer remains a highly lethal malignancy. In order to improve the survival rate of patients with pancreatic cancer, the development of non-invasive diagnostic methods using effective biomarkers is urgently needed. Here, we developed a highly sensitive method to detect DNA methylation in cell-free (cf)DNA samples based on the enrichment of methyl-CpG binding (MBD) protein coupled with a digital PCR method (MBD-ddPCR). Five DNA methylation markers for the diagnosis of pancreatic cancer were identified through DNA methylation microarray analysis in 37 pancreatic cancers. The sensitivity and specificity of the five markers were validated in another independent cohort of pancreatic cancers (100% and 100%, respectively; n = 46) as well as in The Cancer Genome Atlas data set (96% and 90%, respectively; n = 137). MBD-ddPCR analysis revealed that DNA methylation in at least one of the five markers was detected in 23 (49%) samples of cfDNA from 47 patients with pancreatic cancer. Further, a combination of DNA methylation markers and the KRAS mutation status improved the diagnostic capability of this method (sensitivity and specificity, 68% and 86%, respectively). Genome-wide MBD-sequencing analysis in cancer tissues and corresponding cfDNA revealed that more than 80% of methylated regions were overlapping; DNA methylation profiles of cancerous tissues and cfDNA significantly correlated with each other (R = 0.97). Our data indicate that newly developed MBD-ddPCR is a sensitive method to detect cfDNA methylation and that using five marker genes plus KRAS mutations may be useful for the detection of pancreatic cancers.

Prediction of the Probability of Malignancy in Mucinous Cystic Neoplasm of the Pancreas With Ovarian-Type Stroma: A Nationwide Multicenter Study in Japan.

OBJECTIVE: The aim of the study was to develop a formula for predicting the probability of malignancy of mucinous cystic neoplasm (MCN) of the pancreas with ovarian-type stroma. METHODS: A total of 364 patients were enrolled. A total score was calculated as the sum of the approximate integers of the odds ratios of the predictive factors identified by multivariate analysis. The relationship between the total score and pathological results was assessed. RESULTS: A total of 321 patients had benign MCN and 43 had malignant MCN. Five possible predictive factors were analyzed: 56 years or older, high serum carcinoembryonic antigen level, high carbohydrate antigen 19-9 level, tumor size of 51 mm or greater, and the presence of mural nodules. The total score was significantly higher in patients with malignant MCN (median, 24; range, 0-37) compared with benign MCN (median, 5; range, 0-33; P < 0.001). Receiver operating characteristic curve analysis demonstrated that the area under the curve was 0.86, and the sensitivity and specificity of the total score for discriminating malignant MCNs were 72% and 83%, respectively, using a cut-off value of 22. CONCLUSIONS: The current simple formula can predict the malignancy of MCN and may thus contribute to the adequate management of patients with MCN.

Safety and efficacy of endoscopic ultrasound-guided fine needle aspiration for pancreatic masses: A prospective multicenter study.

OBJECTIVES: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) for solid pancreatic lesions has high diagnostic yield. However, few prospective multicenter studies have been performed. We performed a prospective cohort study to evaluate the efficacy and safety of EUS-FNA for diagnosis of solid pancreatic lesions. METHODS: This prospective cohort study involved five hospitals in Japan. The primary outcome was sensitivity of EUS-FNA for diagnosing malignant lesions. We also evaluated parameters of diagnostic sufficiency and the safety of EUS-FNA. RESULTS: In total, 246 patients were enrolled. The absolute values of the parameters evaluated showed no significant differences; however, the percentage changes in the white blood cell counts and C-reactive protein levels after examination were significantly higher, and the percentage change in hemoglobin concentrations was significantly lower. The minor and major complication rates at the time of puncture, 24 h, 7 days and 28 days were 4.1%, 2.8%, 1.6%, and 0.0%, respectively. The true complication rate was 1.2%. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were 97.2%, 88.0%, 96.2%, 100%, and 81.4%, respectively. CONCLUSIONS: EUS-FNA for solid pancreatic lesions has high diagnostic yield and is safe, consistent with previously studies.

Endoscopic Ultrasound-guided Drainage of a Mediastinal Abscess Caused by an Ingested Fish Bone.

Cases of foreign body ingestion are encountered relatively often in clinical settings; however, serious complications are rare. In such cases, mediastinal abscess due to esophageal perforation can become a life-threatening complication. Although highly invasive, surgery is often used as the first-line treatment. We herein report the case of a 65-year-old woman who presented with complaints of progressive odynophagia and dysphagia for 2 weeks following a fish meal. Enhanced cervicothoracic computed tomography demonstrated an enhanced round mass with peripheral contrasted margins. The mass was diagnosed as a mediastinal abscess resulting from esophageal perforation caused by a fish bone. Endoscopic ultrasound-guided abscess drainage (EUS-AD) was performed using a nasobiliary drainage tube (NDT). Two weeks later, the abscess had completely disappeared. EUS-AD was safe and effective in this case; furthermore, external drainage using NDT was suitable for this abscess located very close to the upper esophageal sphincter.

Clinical practice guidelines for safe performance of endoscopic ultrasound/ultrasonography-guided biliary drainage: 2018.

Endoscopic ultrasound/ultrasonography-guided biliary drainage (EUS-BD) is a relatively new modality for biliary drainage after failed or difficult transpapillary biliary cannulation. Despite its clinical utility, EUS-BD can be complicated by severe adverse events such as bleeding, perforation, and peritonitis. The aim of this paper is to provide practice guidelines for safe performance of EUS-BD as well as safe introduction of the procedure to non-expert centers. The guidelines comprised patient-intervention-comparison-outcome-formatted clinical questions (CQs) and questions (Qs), which are background statements to facilitate understanding of the CQs. A literature search was performed using the PubMed and Cochrane Library databases. Statement, evidence level, and strength of recommendation were created according to the GRADE system. Four committees were organized: guideline creation, expert panelist, evaluation, and external evaluation committees. We developed 13 CQs (methods, device selection, supportive treatment, management of adverse events, education and ethics) and six Qs (definition, indication, outcomes and adverse events) with statements, evidence levels, and strengths of recommendation. The guidelines explain the technical aspects, management of adverse events, and ethics of EUS-BD and its introduction to non-expert institutions.

Correction to: Phase II study of sunitinib in Japanese patients with unresectable or metastatic, well-differentiated pancreatic neuroendocrine tumor.

In the original publication of this article, the license subtype should be CC BY and not CC BY-NC.

Invasive Ductal Carcinoma Arising in Mucinous Cystic Neoplasm of Pancreas: A Case Report.

BACKGROUND Mucinous cystic neoplasm (MCN) of the pancreas is a rare mucin-producing cystic neoplasm that has a characteristic histological feature referred to as ovarian-type stroma (OS) underlying the epithelium. Pancreatic ductal carcinoma arises from MCN as a precursor lesion, but data on progression pathways are limited. CASE REPORT A 40-year-old female was referred to our hospital for further investigation of a pancreatic cyst. Further examination showed a 7.0 cm multilocular cyst in the pancreatic tail and a solid mass in the thick septum of the cystic tumor. Distal pancreatectomy and splenectomy were performed. Histological examination revealed a moderately differentiated invasive ductal carcinoma (IDC) with a diameter of 0.5 cm in the thick septum of the cystic lesion and a cyst wall composed of epithelium with low-grade to severe dysplasia. The epithelium covered an OS. Pathological diagnosis was IDC arising in MCN of the pancreas. Immunohistochemical examination showed that MUC1 expression was negative in MCN but positive in IDC. KRAS mutation was observed in both MCN and IDC regions. CONCLUSIONS We present a rare case of moderately differentiated pancreatic IDC arising in MCN. To elucidate the underlying progression pathway, we explored the correlation between KRAS mutation and MUC expression as a clinicopathological parameter.

A multi-institution consensus on how to perform EUS-guided biliary drainage for malignant biliary obstruction.

BACKGROUND AND OBJECTIVES: EUS-guided biliary drainage (EUS-BD) was shown to be useful for malignant biliary obstruction (MBO). However, there is lack of consensus on how EUS-BD should be performed. METHODS: This was a worldwide multi-institutional survey among members of the International Society of EUS conducted in February 2018. The survey consisted of 10 questions related to the practice of EUS-BD. RESULTS: Forty-six endoscopists of them completed the survey. The majority of endoscopists felt that EUS-BD could replace percutaneous transhepatic biliary drainage after failure of ERCP. Among all EUS-BD methods, the rendezvous stenting technique should be the first choice. Self-expandable metal stents (SEMSs) were recommended by most endoscopists. For EUS-guided hepaticogastrostomy (HGS), superiority of partially-covered SEMS over fully-covered SEMS was not in agreement. 6-Fr cystotomes were recommended for fistula creation. During the HGS approach, longer SEMS (8 or 10 cm) was recommended. During the choledochoduodenostomy approach, 6-cm SEMS was recommended. During the intrahepatic (IH) approach, the IH segment 3 was recommended. CONCLUSION: This is the first worldwide survey on the practice of EUS-BD for MBO. There were wide variations in practice, and randomized studies are urgently needed to establish the best approach for the management of this condition.

Long-term outcomes of EUS-guided choledochoduodenostomy using a lumen-apposing metal stent for malignant distal biliary obstruction: a prospective multicenter study.

BACKGROUND AND AIMS: EUS-guided choledochoduodenostomy (EUS-CDS) using conventional tubular stents has been successfully performed. However, EUS-CDS carries a high risk of bile leakage with attendant adverse events. This study aimed to prospectively evaluate the long-term outcome of EUS-CDS using a dedicated lumen-apposing metal stent (LAMS). METHODS: Nineteen patients (mean age, 70.6 years; 12 men) with unresectable malignant diseases were treated in 5 tertiary referral centers. EUS-CDS was performed using a fully covered LAMS with a cautery-enhanced delivery system for EUS-CDS. RESULTS: All stents were successfully deployed without any adverse events. Jaundice improved in 79% of the patients within 7 days and finally in 95%. In 95% of patients the stents remained in good anastomotic position without migration or dislocation during the follow-up period (median, 184 days; range, 12-819). One patient had a fever the day after stent placement. During the follow-up period 5 patients had secondary stent obstruction because of food residue (n = 2), kinking (n = 1), suspected tumor ingrowth (n = 1), and spontaneous dislodgement (n = 1). Five patients developed obstruction in the second portion of the duodenum. The overall adverse event rate was 36.8% (7/19), mostly with mild severity. CONCLUSIONS: This study revealed that the novel dedicated LAMS used has high technical and clinical success rates for EUS-CDS. The adverse events and patency rates are inferior to the historically reported data of a conventional transpapillary metal stent. Development of a more suitable dedicated LAMS is anticipated.

Spontaneous Development of Acute Obstructive Suppurative Pancreatic Ductitis Associated with Pancreatic Carcinoma: A First Case Report.

A 68-year-old man with a history of diabetes mellitus was admitted to our hospital with a diagnosis of acute pancreatitis. Abdominal computed tomography revealed a suspicious tumor in the body of the pancreas, along with a dilated main pancreatic duct and edema of the pancreatic tail. Endoscopic retrograde pancreatography was performed after treating the patient's pancreatitis. When a cannula tip was advanced beyond the stenosis, deep into the distal pancreatic duct, thick white pus was evacuated. A bacteriological examination of the aspirated pancreatic juice revealed Enterobacter cloacae, and a cytological examination revealed adenocarcinoma. The diagnosis was acute obstructive suppurative pancreatic ductitis associated with pancreatic carcinoma.

Feasibility of the unilateral-flange stent for the treatment of benign pancreatic duct stricture: a pilot study.

Endoscopic placement of the plastic stent has been adopted as an initial treatment for chronic pancreatitis with pancreatic duct stricture. Stent fracture while attempting removal is one of the complications of stent exchange. The use of the unilateral-flange stent in these patients has never been reported. We investigated the outcomes associated with the use of this stent with regard to stent exchange and stent-related adverse events. From 2011 to 2015, 9 patients with chronic pancreatitis and main pancreatic duct (MPD) stricture treated with the unilateral-flange stent were included. Eleven endoscopic treatment sessions, 53 endoscopic stent deployments or exchange procedures were analyzed. Technical success rate was 100%. Forty-eight stents were exchanged on a regular basis in 1 to 6-month intervals. Another 5 stent exchange procedures were urgently performed due to stent obstruction and caused pancreatitis (n=2), symptomatic external stent migration (n=2), and concurrent cholangitis (n=1). The rate of symptomatic migration was 3.7%. The mean duration for stent exchange was 29 minutes and no stent fracture occurred during the procedure. Of 11 endoscopic treatment sessions, 7 were successful, 3 were changed to the metallic stents, and 1 was lost to follow-up. According to this study, unilateral-flange stent placement for benign MPD stricture is technically feasible and effective. Stent removal during the exchange period is unchallenging and without stent fracture.

Endoscopic Ultrasound-guided Rendezvous Technique after Failed Endoscopic Retrograde Cholangiopancreatography: Which Approach Route Is the Best?

Objective The endoscopic ultrasound-guided rendezvous technique (EUS-RV) is a salvage method for failed selective biliary cannulation. Three puncture routes have been reported, with many comparisons between the intra-hepatic and extra-hepatic biliary ducts. We used the trans-esophagus (TE) and trans-jejunum (TJ) routes. In the present study, the utility of EUS-RV for biliary access was evaluated, focusing on the approach routes. Methods and Patients In 39 patients, 42 puncture routes were evaluated in detail. EUS-RV was performed between January 2010 and December 2014. The patients were prospectively enrolled, and their clinical data were retrospectively collected. Results The patients' median age was 71 (range 29-84) years. The indications for endoscopic retrograde cholangiopancreatography (ERCP) were malignant biliary obstruction in 24 patients and benign biliary disease in 15. The technical success rate was 78.6% (33/42) and was similar among approach routes (p=0.377). The overall complication rate was 16.7% (7/42) and was similar among approach routes (p=0.489). However, mediastinal emphysema occurred in 2 TE route EUS-RV patients. No EUS-RV-related deaths occurred. Conclusion EUS-RV proved reliable after failed ERCP. The selection of the appropriate route based on the patient's condition is crucial.

Health-related quality of life in a randomised phase III study of gemcitabine plus S-1, S-1 alone and gemcitabine alone for locally advanced or metastatic pancreatic cancer: GEST study.

OBJECTIVE: This study was performed to compare health-related quality of life (HRQOL) of gemcitabine plus S-1 (GS), S-1 alone and gemcitabine alone as first-line chemotherapy for locally advanced or metastatic pancreatic cancer in the GEST (Gemcitabine and TS-1 Trial) study and to assess the impacts of adverse events and tumour response on HRQOL. METHODS: Patients were randomly assigned to receive gemcitabine alone (1000 mg/m2 weekly for 3 of 4 weeks), S-1 alone (80, 100 or 120 mg/day twice daily for 4 of 6 weeks) or GS (gemcitabine at 1000 mg/m2 weekly plus S-1 at 60, 80 or 100 mg/day twice daily for 2 of 3 weeks). HRQOL was assessed using the EuroQoL-5D (EQ-5D) questionnaire at baseline and weeks 6, 12, 24, 48 and 72. EQ-5D scores, quality-adjusted life months (QALMs), quality-adjusted progression-free months (QAPFMs) and time until definitive HRQOL deterioration (TUDD) were compared among the three groups. The impacts of adverse events and tumour response on EQ-5D scores were analysed. RESULTS: Including EQ-5D scores after death as 0, the mean profile was significantly better in the GS than gemcitabine group (difference, 0.069; p=0.003), but not the S-1 group (difference, -0.011; p=0.613). The mean profiles until death were similar in the three groups. QALMs, QAPFMs and TUDD were significantly longer in the GS than gemcitabine group (p<0.001, p<0.001 and p=0.004, respectively), but not the S-1 group (p=0.563, p=0.741 and p=0.701, respectively). Fatigue, anorexia and tumour response were significantly associated with changes in EQ-5D scores. CONCLUSIONS: GS achieved better HRQOL than gemcitabine alone, resulting a good balance between overall survival and HRQOL benefits. S-1 alone provides HRQOL similar to that provided by gemcitabine alone. Preventing fatigue and anorexia and maintaining better response would improve HRQOL.

A case of API2-MALT1-positive gastric MALT lymphoma with concomitant diffuse large B-cell lymphoma.

API2-MALT1 translocation-positive gastric marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT) lymphoma is thought to transform to diffuse large B-cell lymphoma (DLBCL) rarely. A 69-year-old man presented with epigastralgia. Esophagogastroduodenoscopy showed multiple ulcerations in the stomach. Endoscopic biopsies revealed MALT lymphoma, with Helicobacter pylori infection. The patient underwent eradication therapy with no improvement, and was thereafter followed without additional therapy at his request. Twelve years after initial diagnosis, follow-up computed tomography (CT) showed multiple nodules in bilateral lungs, and a needle biopsy revealed MALT lymphoma, the same as in the stomach and API2-MALT1 translocation was found. Because he again refused additional therapy, follow-up was continued. 15 years after initial diagnosis, CT showed lymphadenopathy at the splenic hilum. At first we suspected disease progression of gastric MALT lymphoma, however a needle biopsy revealed DLBCL without API2-MALT1. Thus, the tumor at the splenic hilum was finally diagnosed as a de novo DLBCL as a second malignancy. Although treatment with rituximab given his age and his wishes was attempted, he died of DLBCL 15 years after the initial diagnosis. We experienced an API2-MALT1-positive gastric MALT lymphoma with concomitant DLBCL, not transformed to DLBCL over a 15-year clinical course.

Optimal intake of clear liquids during preparation for afternoon colonoscopy with low-volume polyethylene glycol plus ascorbic acid.

BACKGROUND AND STUDY AIMS: The standard colonoscopy preparation regimen in Japan for afternoon procedures is sequential intake of 1 L of polyethylene glycol electrolyte lavage solution containing ascorbic acid (PEG-ASC), 0.5 L of clear liquid, 0.5 L of PEG-ASC, and finally 0.25 L of clear fluids (all at a rate of 0.25 L every 15 min). However, this regimen seems poorly tolerated and complicated for many patients compared to previous regimen of polyethylene glycol electrolyte lavage solution. The aim of this study was to evaluate an alternate regimen of 0.5 L of PEG-ASC followed by 0.25 L clear liquids, repeated 3 times. PATIENTS AND METHODS: This was a single-blinded, non-inferiority, randomized controlled study. Subjects were randomized to the standard regimen or the alternate regimen using a web-based registry system. All patients were instructed to eat a pre-packaged, low residue diet and to take sodium picosulfate hydrate the day before colonoscopy. The Boston Bowel Preparation Scale was used to evaluate bowel cleansing, and a 3-point scale was used to assess mucosal visibility. The primary endpoint was successful bowel cleansing. The acceptability, tolerability, safety, and endoscopic findings of these two regimens were secondary endpoints. RESULTS: A total of 409 patients were randomized to either the standard regimen (n = 204, males 54.0 %, mean age 65.5 years) or the alternate regimen (n = 205, 54.6 %, 65.0 years). The rates of successful bowel cleansing were 71.1 % (64.3 - 77.2 %) with the standard regimen vs. 75.1 % (68.6 - 80.9 %) with the alternate regimen (95 % lower confidence limit, for the difference = - 4.6, non-inferiority P  < 0.05). No significant differences were found in tolerability, safety, and endoscopic findings. CONCLUSION: The alternate regimen and standard regimen are clinically equivalent with respect to cleansing efficacy and acceptability, tolerability, safety, and endoscopic findings. These results are good news for patients with difficulty drinking the first liter of PEG-ASC.