Effects of colorectal endoscopic submucosal dissection on postoperative abdominal symptoms: a prospective observational study.

BACKGROUND: Endoscopic submucosal dissection (ESD) is an effective procedure to resect large superficial gastrointestinal neoplasms. In gastric ESD, several studies showed the relationship between postoperative abdominal symptoms and endoscopic treatment. However, the influence of colorectal ESD on abdominal symptoms after treatment is still unknown. To the best of our knowledge, this is the first prospective multicenter study performed to investigate the impact of colorectal ESD on postoperative abdominal symptoms. This study aimed to clarify the association between change of abdominal symptoms and ESD. METHODS: This study was a prospective multicenter observational trial that enrolled 141 out of 171 patients who underwent colorectal ESD and answered the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire from March 2015 to August 2019. We evaluated abdominal symptoms in the patients using the GSRS questionnaire before ESD and a few weeks after ESD. RESULTS: Comparing the GSRS before and after ESD, overall scores changed from 1.58 ± 0.58 to 1.48 ± 0.48, and the five subscales (reflux syndrome, abdominal pain, indigestion syndrome, diarrhea syndrome, and constipation syndrome) were slightly improved. Overall scores, indigestion syndrome, and constipation syndrome were statistically significantly different before and after ESD (P < 0.05). CONCLUSIONS: In GSRS, a score of ≥ 3 is often treated as a clinically significant symptom. Therefore, our findings indicated that there was no clinically significant difference. For this reason, colorectal ESD does not affect postoperative abdominal symptoms and is considered a minimally invasive treatment. The analysis of the impact of colon ESD on gastrointestinal symptoms UMIN000016914.

Comparison of the diagnostic performance of NBI, Laser-BLI and LED-BLI: a randomized controlled noninferiority trial.

BACKGROUND AND AIMS: New image-enhanced endoscopy (IEE), blue Light Imaging (LED-BLI) is launched in USA and Europe, whereas Blue Laser Imaging (Laser-BLI) is available only Asian and some countries. No studies have directly compared the diagnostic accuracy of narrow band imaging (NBI), Laser-BLI and LED-BLI for colorectal tumors. The present study aimed to compare the diagnostic accuracy of the three methods for colorectal tumor using the NBI international colorectal endoscopic (NICE) classification and the Japanese NBI Expert Team (JNET) classifications. METHODS: This was a multi-center evaluator-blinded, randomized control trial of patients who underwent endoscopic colorectal tumor resection. The patients were randomly assigned to NBI, Laser-BLI or LED-BLI. Cropped images were sent to blinded external evaluators and diagnosed according to NICE and JNET classifications. The diagnostic accuracy of each endoscopy system was compared with non-inferiority test. RESULTS: A total of 619 colonic tumors were resected from 230 patients and evaluated by external four evaluators. The diagnostic accuracy of NBI for NICE 1, NICE 2, NICE 3 was 90.6%, 90.3% and 99.5%, respectively and for JNET 1, JNET 2A, JNET 2B and JNET 3, it was 94.6%, 72.0%, 79.2% and 99.1%, respectively. In non-inferiority test, Laser-BLI and LED-BLI revealed non-inferiority to NBI in all NICE and JNET categories (p<0.001). CONCLUSIONS: Laser-BLI and LED-BLI had high diagnostic accuracy and non-inferiority of NBI, especially for hyperplastic polyp/sessile serrated lesion and low-grade dysplasia. This is first trial to compare the diagnostic accuracy with NBI, Laser-BLI and LED-BLI and useful to understand the position of each IEE. This trial was registered as UMIN000032107.

Elobixibat Effectively Relieves Chronic Constipation in Patients with Cancer Regardless of the Amount of Food Intake.

BACKGROUND: Constipation is a common, distressing complication in patients with cancer receiving palliative care. Elobixibat is a novel inhibitor of the ileal bile acid transporter that is used to treat chronic constipation by stimulating bowel function. However, its efficacy in patients with cancer has not been examined. This study investigated the drug's effectiveness in patients with cancer with chronic constipation. PATIENTS AND METHODS: This prospective-sampling, single-center, observational study included hospitalized patients with cancer diagnosed, using the Rome IV criteria, with chronic constipation. Within 2 weeks of hospitalization, each participant was administered elobixibat (5-15 mg) daily until discharge. Spontaneous bowel movements (SBMs), complete spontaneous bowel movements (CSBMs), Bristol stool form scale (BSFS) scores, and the Patient Assessment of Constipation Quality of Life questionnaire (PAC-QOL) scores were assessed before and after elobixibat administration. We also evaluated the relationship between the amount of food consumed and the SBM frequency. RESULTS: Among the 83 participants, the mean pre- and post-treatment frequencies of daily SBMs were 0.3 and 1.2 (p < .0001) and those of CSBMs were 0.1 and 0.6 (p < .0001), respectively. The mean pretreatment BSFS score was 1.6, whereas the post-treatment value was 3.5 (p < .0001); the mean PAC-QOL score (overall) improved from 1.01 to 0.74 (p = .01). There was no significant change in the daily SBM frequency between fasting and feeding states (1.2 vs. 1.3; p = .8), and there was no correlation between the amount of food intake and the SBM frequency after elobixibat administration (r = .03). Serious adverse events were not observed. CONCLUSION: This study showed that elobixibat is safe and effective for patients with cancer with chronic constipation, regardless of the food intake amount. IMPLICATIONS FOR PRACTICE: Elobixibat was effective at relieving chronic constipation in patients with various cancers. Serious adverse events were not observed, and the relief of constipation was independent of variation in food intake.

Efficacy of sedation with dexmedetomidine plus propofol during esophageal endoscopic submucosal dissection.

BACKGROUND AND AIM: During endoscopic submucosal dissection for superficial esophageal cancer, patient body movement can sometimes occur, which may cause discontinuation of the procedure. Propofol and dexmedetomidine have recently been found to be useful sedatives for endoscopic submucosal dissection. This study investigated whether sedation using propofol plus dexmedetomidine can suppress the patient's body movements during esophageal endoscopic submucosal dissection and compared this combination with sedation using propofol alone. METHODS: This was a prospective double-blind randomized controlled trial. Patients with superficial esophageal cancers who underwent esophageal endoscopic submucosal dissection at Yokohama City University Hospital were prospectively enrolled and were randomly assigned to the propofol and the propofol plus dexmedetomidine groups. The primary endpoint was the incidence of restlessness. The secondary endpoints were the satisfaction score, maintenance dose of propofol, and number of rescue propofol injections. RESULTS: Sixty-six patients (propofol group: n = 33; combination group: n = 33) were included. The combination group had a significantly lower incidence of restlessness than the propofol group (3.0% vs 27.3%, P = 0.02). In the combination group, the satisfaction scores of the endoscopists were significantly higher, the maintenance dose of propofol was significantly lower, and the number of rescue propofol injections was lower than those in the propofol group (3.0% vs 18.2%, P < 0.001). Although the incidence of bradycardia was significantly higher in the combination group (30.3% vs 3.0%, P < 0.01), no serious adverse effects occurred. CONCLUSION: The propofol plus dexmedetomidine combination provided excellent sedation that effectively suppressed the patient's body movements during esophageal endoscopic submucosal dissection.

Relationship between Stool Form and Quality of Life in Patients with Chronic Constipation: An Internet Questionnaire Survey.

INTRODUCTION: Chronic constipation (CC) is a highly prevalent functional bowel disorder with low treatment satisfaction and impaired quality of life (QOL). However, physicians tend to emphasize only "stool frequency," and relationship between "stool form" and QOL remains unclear. In this study, we aimed to investigate the actual situation of CC treatment in Japan and elucidate the relationship between stool form and QOL in patients with CC. METHODS: We conducted an online questionnaire survey in September 2018 targeting Japanese adult patients already diagnosed with CC and taking prescribed drugs. Assessments included the type of drug treatment, treatment duration, frequency of drug use, frequency of bowel movements (BMs), Bristol Stool Form Scale (BSFS), and Japanese version of the Patient Assessment of Constipation QOL (PAC-QOL) scores. Relationship between BSFS and Japanese PAC-QOL scores was analyzed, and most important factor that influences QOL was investigated. RESULTS: A total of 614 subjects were enrolled. Of these, 398 (64.8%) regularly used magnesium oxide and 162 (26.4%) used stimulant laxative, especially 81 (50.0%) used stimulant laxative "everyday." Mean score of the PAC-QOL was 1.29 ± 0.74, and the lowest score (highest QOL) of 0.94 ± 0.61 was observed in BSFS type 4. Significant difference was seen between BSFS type 4 and all the other types except type 7. Multivariate analysis revealed that normal stool form (BSFS type 4) and BMs ≥3/week are strongly related to decreases of PAC-COL score. In BSFS types 6 and 7, 36% of individuals experienced self-discontinuation of prescribed drugs and 53% self-reduced drug intake because of excessive effects. CONCLUSIONS: Stool form and frequency of BMs are relevant to QOL, especially normal stool form (BSFS type 4) is important for improving the QOL in patients with constipation. Physicians should focus on "stool form" and reconsider the prescription especially in BSFS types 6-7 patients.

The efficacy of a leukotriene receptor antagonist in the treatment of human rectal aberrant crypt foci: a nonrandomized, open-label, controlled trial.

BACKGROUND: Leukotriene receptor antagonists (LTRAs) are broadly used for the management of allergic asthma and have recently been indicated to inhibit carcinogenesis and cancer cell growth. In colorectal cancer (CRC) chemoprevention studies, the occurrence of adenoma or CRC itself is generally set as the trial endpoint. Although the occurrence rate of CRC is the most confident endpoint, it is inappropriate for chemoprevention studies because CRC incidence rate is low in the general population and needed for long-term monitoring. Aberrant crypt foci (ACF), defined as lesions containing crypts that are larger in diameter and darker in methylene blue staining than normal crypts, are regarded to be a fine surrogate biomarker of CRC. Therefore, this prospective study was designed to explore the chemopreventive effect of LTRA on colonic ACF formation and the safety of the medicine in patients scheduled for a poly resection as a pilot trial leading the CRC chemoprevention trial. METHODS: This study is a nonrandomized, open-label, controlled trial in patients with colorectal ACF and polyps scheduled for a polypectomy. Participants meet the inclusion criteria will be recruited, and the number of ACF in the rectum will be counted at the baseline colonoscopic examination. Next, the participants will be assigned to the LTRA or no treatment group. Participants in the LTRA group will continue 10 mg of oral montelukast for 8 weeks, and those in the no treatment group will be observed without the administration of any additional drugs. At the end of the 8-week LTRA intervention period, a polypectomy will be conducted to evaluate the changes in the number of ACF, and cell proliferation in the normal colorectal epithelium will be analyzed. DISCUSSION: This will be the first study to investigate the effect of LTRAs on colorectal ACF formation in humans. TRIAL REGISTRATION: This trial has been registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry as UMIN000029926 . Registered 10 November 2017.

The efficacy of aspirin and metformin combination therapy in patients with rectal aberrant crypt foci: a double-blinded randomized controlled trial.

BACKGROUND: The incidence and mortality rates of colorectal cancer (CRC) continue to increase worldwide. Therefore, new preventive strategies are needed to lower the burden of this disease. Previous studies reported that aspirin could suppress the development of sporadic colorectal adenoma. In addition, metformin is a biguanide derivative that is long widely used for the treatment of diabetes mellitus and has recently been suggested to have a suppressive effect on carcinogenesis and cancer cell growth. Both drugs exhibit a chemopreventive effect, but their efficacy is limited. Aberrant crypt foci (ACF), defined as lesions containing crypts that are larger in diameter and stain more darkly with methylene blue than normal crypts, are more prevalent in patients with cancer and adenomas, and considered a reliable surrogate biomarker of CRC. Thus, we designed a prospective trial as a preliminary study prior to a CRC chemoprevention trial to evaluate the chemopreventive effect of aspirin combined with metformin on colorectal ACF formation in patients scheduled for polypectomy. METHODS: This study is a double-blind randomized controlled trial that will be conducted in patients with both colorectal ACF and colorectal polyps scheduled for polypectomy. Eligible patients will be recruited for the study and the number of ACF in the rectum will be counted at the baseline colonoscopy. Then, the participants will be allocated to one of the following two groups; the aspirin plus placebo group or the aspirin plus metformin group. Patients in the aspirin plus placebo group will receive oral aspirin (100 mg) and placebo for 8 weeks, and those in the aspirin plus metformin group will receive oral aspirin (100 mg) and metformin (250 mg) for 8 weeks. After 8 weeks of administration, polypectomy will be performed to evaluate changes in the number of ACF, and the cell-proliferative activity in the normal colorectal mucosa and colorectal polyps. DISCUSSION: This is the first study proposed that will explore the effect of aspirin combined with metformin on the formation of colorectal ACF in humans. TRIAL REGISTRATION: This trial has been registered in the University Hospital Medical Information Network (UMIN) Clinical Trials Registry as UMIN000028259 . Registered 17 July 2017.

Continued Use of a Single Antiplatelet Agent Does Not Increase the Risk of Delayed Bleeding After Colorectal Endoscopic Submucosal Dissection.

BACKGROUND: With the aging of the population and rising incidence of thromboembolic events, the usage of antiplatelet agents is also increasing. There are few reports yet on the management of antiplatelet agents for patients undergoing colorectal endoscopic submucosal dissection (ESD). AIMS: The aim of this study is to evaluate whether continued administration of antiplatelet agents is associated with an increased rate of delayed bleeding after colorectal ESD. METHODS: A total of 1022 colorectal neoplasms in 927 patients were dissected at Yokohama City University Hospital and its three affiliate hospitals between July 2012 and June 2017. We included the data of 919 lesions in the final analysis. The lesions were divided into three groups: the no-antiplatelet group (783 neoplasms), the withdrawal group (110 neoplasms), and the continuation group (26 neoplasms). RESULTS: Among the 919 lesions, bleeding events occurred in a total of 31 (3.37%). The rate of bleeding after ESD was 3.3% (26/783), 4.5% (5/110), and 0% (0/26), respectively. There were no significant differences in the rate of bleeding after ESD among the three groups (the withdrawal group vs. the no-antiplatelet group, the continuation group vs. the no-antiplatelet group, and the withdrawal group vs. the continuation group). CONCLUSIONS: Continued administration of antiplatelet agents is not associated with any increase in the risk of delayed bleeding after colorectal ESD. Prospective, randomized studies are necessary to determine whether treatment with antiplatelet agents must be interrupted prior to colorectal ESD in patients who are at a high risk of thromboembolic events.

Diagnostic Ability of Ultrasonography Compared with Computed Tomography for Assessing Rectal Feces.

Objectives: Chronic constipation is a common gastrointestinal disorder, and management is crucial. Computed tomography (CT) is useful for evaluating rectal fecal mass but limited owing to radiation exposure, cost, and inaccessibility at certain facilities. Ultrasonography (US) avoids these pitfalls, but it is unknown whether it accurately assesses rectal feces. In this study, we evaluated the diagnostic performance of US compared with CT as the gold standard for assessing rectal feces. Methods: We prospectively evaluated rectal fecal mass retention using US performed within 1 h of CT to assess the degree of agreement between methodologies. Rectal stool findings were evaluated on three levels: no stool (R1), presence of stool (R2), and hard stool filling (R3). Results: The sample included 100 patients (55 men, 45 women), of whom 47 were constipated. The kappa coefficients for rectal content detection were excellent between US and CT (p <0.001). Eighty-two cases (R1: 46 cases; R2: 28 cases; R3: 8 cases) were matched with CT and US findings, and 18 were not. Cases that did not match had low urine or high gas volumes. CT and US findings showed high agreement in constipation (kappa coefficient 0.674, p <0.001) and non-constipation groups (kappa coefficient 0.677, p <0.001). All cases with R3 on CT were found in the constipation group, while more than half of the cases with R1 on CT were in the non-constipation group. Conclusions: CT and US showed high agreement in evaluating rectal fecal mass retention, indicating that US can substitute CT.

Efficacy and safety of rifaximin in patients with chronic intestinal pseudo-obstruction: a randomized, double-blind, placebo-controlled, phase II-a exploratory trial.

Chronic intestinal pseudo-obstruction (CIPO) is a rare intractable disease with limited treatment options. Small intestinal bacterial overgrowth (SIBO) often co-occurs with several diseases, including CIPO. While rifaximin (RFX) is effective in treating SIBO, its efficacy for CIPO remains unclear. Here, we aimed to investigate the efficacy and safety of RFX in adult patients with CIPO. Twelve patients were randomly assigned to receive RFX (400 mg three times daily, n=8) or a placebo (PBO, n=4) for 4 weeks. The global symptom score for abdominal bloating (GSS-bloating) and an original whole gastrointestinal symptoms score (O-WGSS) were collected, and a glucose hydrogen breath test (GHBT) and abdominal computed tomography (CT) were performed. No significant differences were observed in the primary endpoint. GSS-bloating improved by 75% and 25% in the PBO and RFX groups, respectively, and O-WGSS improved by 25% in both groups. No significant differences were observed in secondary and other endpoints, including the SIBO eradication rate in the GHBT and small intestinal volume on CT. In a post hoc analysis of SIBO-positive patients with CIPO (4/4 and 4/8 in the PBO and RFX groups), SIBO was eradicated in 25% and 75% of the patients (PBO and RFX groups, respectively) at the end of treatment, indicating a high eradication rate in the RFX group. Furthermore, the small intestinal gas volume decreased in the RFX group, and no severe adverse events occurred. Although no significant improvements were observed in subjective indicators, RFX may be beneficial in alleviating SIBO and reducing the small intestinal gas volume in SIBO-positive patients with CIPO.

The Prevalence and Characteristics of Symptomatic Uncomplicated Diverticular Disease Among Asian Patients With Unexplained Abdominal Symptoms.

Background/Aims: The precise incidence of symptomatic uncomplicated diverticular disease (SUDD) and its effects on the quality of life (QOL) remain unclear, particularly in Asian patients with right-sided SUDD. We assess the prevalence of SUDD and its impact on QOL in a real-world population. Methods: Five institutional cohorts of patients who received outpatient treatment for unexplained abdominal symptoms from January 15, 2020 to March 31, 2022, were included. All patients underwent colonoscopy. SUDD was defined as the presence of recurrent abdominal symptoms, particularly pain in the lower right or left quadrant lasting > 24 hours in patients with diverticulosis at the site of pain. The 36-item short-form health survey was used to assess QOL. Results: Diverticula were identified in 108 of 361 patients. Among these 108 patients, 31% had SUDD, which was right-sided in 39% of cases. Of the 50 patients with right-sided diverticula, 36% had SUDD, as did 15 of 35 patients with left-sided diverticula (43%). Among the 33 patients with SUDD, diverticula were right-sided, left-sided, and bilateral in 39%, 45%, and 15% of patients, respectively. Diarrhea was more frequent in the SUDD group than in the non-SUDD group. Patients with SUDD had significantly lower physical, mental, and role/social component scores than those without SUDD. Conclusions: It is important to recognize that patients with SUDD account for as high as 31% of outpatients with unexplained abdominal symptoms; these patients have diarrhea and a low QOL. The presence of right-sided SUDD was characteristic of Asian patients.

Prior appendectomy and cerebral infarction as potential risk factors for recurrent ischemic colitis: A retrospective observational study.

Background and Aim: Ischemic colitis (IC) is a benign disease associated with acute lower gastrointestinal bleeding and frequent recurrence. While several studies have investigated risk factors for IC onset, few have assessed the risk factors for recurrent IC. This study aimed to identify risk factors for recurrent IC. Methods: Potential risk factors for recurrence were assessed by examining medical records and laboratory findings in this single-center retrospective study. We extracted the following data from the patients' medical records: patient characteristics, clinical signs and symptoms, laboratory findings, method of treatment, length of hospital stay, disease course, and the frequency of IC morbidities. Patients with IC were selected from a total of 439 312 patients over an 11-year period. Patients were divided into recurrent and nonrecurrent IC groups. Results: In total, 225 patients met the diagnostic criteria for IC during the specified study period; of these, 204 patients (90.7%) and 21 patients (9.3%) were included in the nonrecurrent and recurrent IC groups, respectively. Univariate and multivariate analyses showed a significant association between IC recurrence and both cerebral infarction (P = 0.008, odds ratio [OR] = 6.3) and history of appendectomy (P = 0.0005, OR = 6.2). The median (interquartile range [IQR]) follow-up time for all patients was 1556 (353-2768) days; this was much longer than the median (IQR) time to recurrence of 291 (64-907) days in the recurrent IC group. Conclusion: The results of this study suggest that prior cerebral infarction and appendicectomy may be risk factors for IC recurrence.

Clinicopathological features of endoscopically treated early gastric cancer with lymphovascular infiltration.

PURPOSE: Lymphovascular infiltration (LVI) may play a critical role in radicality and prognostic assessment of early gastric cancer (EGC). However, risk factors for LVI in endoscopically resected EGC remain unknown. This study evaluated the clinicopathological characteristics and prognoses of patients who underwent endoscopic resection of EGC to identify potential risk factors of LVI. METHODS: A cross-sectional study of patients who received gastric endoscopic submucosal dissection between February 1, 2012, and December 31, 2019, at two institutions was conducted. Among 1,462 lesions, 943 met the criteria for radical treatment considering features other than LVI and were included. The lesions were classified based on the presence of LVI. The clinicopathological characteristics of the two groups were compared. RESULTS: LVI was detected in 17 lesions (1.8%). The positivity rates of LVI were 0.7% (7/903) for intramucosal cancer and 25% (10/40) for submucosally invasive cancer. The LVI positivity rate was significantly higher for mixed-type cancer (lesions containing differentiated and undifferentiated-type carcinoma) than for non-mixed-type cancer (35.3 vs. 2.8%; P < 0.001) and for submucosally invasive cancer than for intramucosal cancer (58.8 vs. 3.2%; P < 0.001). In the multivariate logistic regression analysis, independent risk factors for LVI were mixed-type cancer (odds ratio; 95% confidence interval: 23.9; 5.0-115; P < 0.001) and submucosal invasion (58.7; 16.0-215; P < 0.001). CONCLUSIONS: Mixed-type cancer and submucosal invasion were risk factors for LVI in endoscopically resected EGC. These factors may play a critical role in the radicality and prognostic assessment of EGC.

Strain-level detection of Fusobacterium nucleatum in colorectal cancer specimens by targeting the CRISPR-Cas region.

IMPORTANCE: Fusobacterium nucleatum is one of the predominant oral bacteria in humans. However, this bacterium is enriched in colorectal cancer (CRC) tissues and may be involved in CRC development. Our previous research suggested that F. nucleatum is present in CRC tissues originating from the oral cavity using a traditional strain-typing method [arbitrarily primed polymerase chain reaction (AP-PCR)]. First, using whole-genome sequencing, this study confirmed an exemplary similarity between the oral and tumoral strains derived from each patient with CRC. Second, we successfully developed a method to genotype this bacterium at the strain level, targeting the clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated system, which is hypervariable (defined as F. nucleatum-strain genotyping PCR). This method can identify F. nucleatum strains in cryopreserved samples and is significantly superior to traditional AP-PCR, which can only be performed on isolates. The new methods have great potential for application in etiological studies of F. nucleatum in CRC.

Natural History of Chronic Intestinal Pseudo-obstruction and Need for Palliative Care.

Background/Aims: Natural history of chronic intestinal pseudo-obstruction (CIPO), a rare disease characterized by episodes of non-mechanical obstruction, is unclear in adults. This study evaluates the clinical course of CIPO and palliative care needs of patients. Methods: From October 2010 to September 2021, 74 patients who underwent cine MRI and had a definitive diagnosis of CIPO were prospectively included. We investigated disease etiology and outcomes, age at onset, nutritional status at consultation (body mass index and serum albumin), hydrogen breath test results, and total parenteral nutrition (TPN) during the disease course. Results: Forty-seven patients (64%) were women, with a mean age of 44 years at onset and 49 years at diagnosis. Primary CIPO was observed in 48 patients (65%). Secondary CIPO was observed in 26 cases (35%), of whom 18 (69%) had scleroderma. The mean body mass index, serum albumin level, and hydrogen breath test positivity rate were 17 kg/m2, 3.8 mg/dL, and 60%, respectively. TPN and invasive decompression therapy were required by 23 (31%) and 18 (24%) patients, respectively. Intestinal sterilization was performed in 51 (69%) patients and was effective in 33 (65%); of these, 28 (85%) were taking metronidazole. Seven (9%) patients used opioids. There were 9 deaths (12%), including 5 (56%) from infection and 2 (22%) from suicide. Of the deaths, 6 (67%) and 4 (44%) underwent TPN management and decompression therapy, respectively. Fifty-one patients (69%) wanted palliative care. Conclusion: CIPO is a rare, severe, and under-recognized disease. Standardization of treatment strategies, including palliative care and psychiatric interventions, is desired.

Leukotriene Receptor Antagonist Therapy for the Chemoprevention of Human Rectal Aberrant Crypt Foci: Nonrandomized, Open-Label, Controlled Trial.

Leukotriene receptor antagonists (LTRA) are widely used drugs for treating allergic asthma, and they have recently been suggested to have a suppressive effect on carcinogenesis and cancer cell proliferation. Aberrant crypt foci (ACF) are considered a reliable surrogate biomarker of colorectal cancer. This prospective study explored the chemopreventive effect of an LTRA on colonic ACF formation and the safety of the medicine in patients as a pilot trial leading to a colorectal cancer chemoprevention trial.This was a nonrandomized, open-label, controlled trial in patients with colorectal ACFs. The participants were allocated to LTRA or observation groups. Patients in the LTRA group received 10 mg of montelukast orally daily for 8 weeks. After the intervention, colonoscopy was performed to evaluate the changes in the number of ACFs.From November 2017 to March 2020, 40 patients were enrolled. The first 30 were assigned to the LTRA group, and the remaining 10 were assigned to the observation group. In the LTRA group, the mean change in the number of ACFs per patient at 8 weeks from baseline was -2.4 ± 2.2, while the mean change in the observation group was 0.4 ± 2.3 (P = 0.002). There were no severe adverse events.This is the first study to explore the effect of LTRAs against colorectal ACF formation in humans. LTRAs are potential candidates for chemoprevention in colorectal cancer. PREVENTION RELEVANCE: We conducted the first LTRA chemoprevention trial for human rectal ACFs, which is considered a surrogate marker of colorectal carcinogenesis. 8-week treatment with LTRA suppressed ACF formation and cell proliferation in colonic epithelium. LTRAs are possible candidates for chemoprevention in colorectal cancer. See related Spotlight, p. 637.

Exploratory, multicenter, open-label study to evaluate the effects of linaclotide in patients with chronic constipation with an insufficient response to magnesium oxide: A study protocol.

Background: Chronic constipation leads to poor quality of life, and treatment remains unsatisfactory for patients. In Japan, magnesium oxide has been commonly used as the first choice of treatment for constipation; however, there are some cases of low satisfaction with magnesium oxide treatment. Linaclotide has recently been used to treat chronic constipation. In this study, we will examine whether linaclotide improves symptoms and quality of life in patients showing insufficient response to magnesium oxide. Methods: This is an exploratory multicenter open-label study. The target number of patients is 64: 32 patients with and 32 without abdominal symptoms. Patients with chronic idiopathic constipation or irritate bowel syndrome with constipation diagnosed according to the Rome-IV criteria are eligible. Patients prescribed 0.99-2 g/day of magnesium oxide for at least 4 weeks will be included. Those who consent to the study will continue taking magnesium oxide for 2-4 weeks, and defecation will be documented. Patients who meet the criteria will be prescribed linaclotide (0.5 mg) daily for 12 weeks. The primary endpoint is a change in the Japanese version of the Patient Assessment of Constipation Quality of Life (JPAC-QOL) score after 12 weeks of treatment. Conclusion: This is the first study to investigate the usefulness of linaclotide as a second-line treatment for chronic constipation. We will test the efficacy of treatment of constipation in patients with inadequate response to magnesium oxide. Trial registration: This study is registered with the Japan Registry of Clinical Trials (jRCT, jRCTs031200048).

Rationale and design of a multicentre, 12-week, randomised, double-blind, placebo-controlled, parallel-group, investigator-initiated trial to investigate the efficacy and safety of elobixibat for chronic constipation.

INTRODUCTION: Chronic constipation (CC) is a functional disorder that negatively impacts the quality of life of patients. This is a protocol for a multicentre, 12-week, randomised, double-blind, placebo-controlled study to test the efficacy and safety of elobixibat (EXB) versus placebo in patients with CC. METHODS AND ANALYSIS: This will be a multicentre, double-blind, placebo-control, randomised controlled trial. A total of 100 adult patients with CC, diagnosed based on Rome IV criteria, who fulfil the inclusion/exclusion criteria will be enrolled. The patients will be randomly assigned to receive EXB (10 mg) or placebo treatment (n=50 per group). Blood tests and stool sampling will be performed 12 weeks following initiation of treatment and questionnaires will be issued to participants. The primary outcome will be the change in complete spontaneous bowel movements after 12 weeks of administration. The secondary outcomes will include the change in Japanese Patient Assessment of Constipation Quality of Life and absolute serum and faecal bile acid. ETHICS AND DISSEMINATION: Ethics approval has been obtained from Yokohama City University Certified Institutional Review Board before participant enrolment. The results of this study will be submitted for publication in international peer-reviewed journals and the key findings will be presented at international scientific conferences. PROTOCOL VERSION: V.3.0, 15 June 2021. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov (number NCT04784780).

Effectiveness of Naldemedine Compared with Magnesium Oxide in Preventing Opioid-Induced Constipation: A Randomized Controlled Trial.

Opioid-induced constipation (OIC) may occur in patients receiving opioid treatment, decreasing their quality of life (QOL). We compared the effectiveness of magnesium oxide (MgO) with that of naldemedine (NAL) in preventing OIC. This proof-of-concept, randomized controlled trial (registration number UMIN000031891) involved 120 patients with cancer scheduled to receive opioid therapy. The patients were randomly assigned and stratified by age and sex to receive MgO (500 mg, thrice daily) or NAL (0.2 mg, once daily) for 12 weeks. The change in the average Japanese version of Patient Assessment of Constipation QOL (JPAC-QOL) from baseline to 2 weeks was assessed as the primary endpoint. The other endpoints were spontaneous bowel movements (SBMs) and complete SBMs (CSBMs). Deterioration in the mean JPAC-QOL was significantly lower in the NAL group than in the MgO group after 2 weeks. There were fewer adverse events in the NAL group than in the MgO group. Neither significant differences in the change in SBMs between the groups nor serious adverse events/deaths were observed. The CSBM rate was higher in the NAL group than in the MgO group at 2 and 12 weeks. In conclusion, NAL significantly prevented deterioration in constipation-specific QOL and CSBM rate compared with MgO.

Rationale and design of a multicenter, single-group, open-label trial aiming at investigating the effectiveness of elobixibat for loss of defecation desire in patients with chronic constipation.

Background: Approximately 60% of patients with chronic constipation (CC) have a significantly higher rate of loss of defecation desire (LODD). Bile acids are expected to have a restorative effect on defecation desire (DD) because they lower the rectal sensory threshold, which is an objective index of DD. Elobixibat (EXB) specifically inhibits the ileal bile acid transporter/apical sodium-dependent bile acid transporter, which is a transporter involved in the reabsorption of bile acids in the terminal ileum. This study aims to investigate the LODD improvement rate in patients with CC after 4 weeks of EXB treatment. Methods: A total of 40 adult patients with CC who meet the eligibility criteria will be enrolled. Patients will receive oral EXB (10 mg/day) for 4 weeks. A patient diary will be provided daily at 4 weeks after treatment. The primary endpoint will be the percentage LODD improvement at week 4 of the treatment period from week 2 of the observation period using questionnaires. Ethics and dissemination: Ethical approval was obtained from the Yokohama City University Certified Institutional Review Board prior to participant enrolment (approval number: CRB21-008). The results of this study will be submitted for publication in international peer-reviewed journals, and key findings will be presented at international scientific conferences. Participants desiring the results of this study will be directly contacted for data dissemination. Trial registration: This trial was registered at ClinicalTrials.gov (NCT05165199). Protocol version: 1.0, September 21, 2021.