Assessing risk stratification in long-term outcomes of rectal neuroendocrine tumors following endoscopic resection: a multicenter retrospective study.

OBJECTIVES: While endoscopic resection of rectal neuroendocrine tumors (NETs) has significantly increased, long-term data on risk factors for recurrence are still lacking. Our aim is to analyze the long-term outcomes of patients with rectal NETs after endoscopic resection through risk stratification. METHODS: In this multicenter retrospective study, we included patients who underwent endoscopic resection of rectal NETs from 2009 to 2018 and were followed for ≥12 months at five university hospitals. We classified the patients into three risk groups according to the clinicopathological status of the rectal neuroendocrine tumors: low, indeterminate, and high. The high-risk group was defined if the tumors have any of the followings: size ≥ 10 mm, lymphovascular invasion, muscularis propria or deeper invasion, positive resection margins, or mitotic count ≥2/10. RESULTS: A total of 346 patients were included, with 144 (41.6%), 121 (35.0%), and 81 (23.4%) classified into the low-, indeterminate-, and high-risk groups, respectively. Among the high-risk group, seven patients (8.6%) received salvage treatment 28 (27-67) days after the initial endoscopic resection, with no reported extracolonic recurrence. Throughout the follow-up period, 1.1% (4/346) of patients experienced extracolonic recurrences at 56.5 (54-73) months after the initial endoscopic resection. Three of these patients (75%) were in the high-risk group and did not undergo salvage treatment. The risk of extracolonic recurrence was significantly higher in the high-risk group compared to the other groups (p = 0.039). CONCLUSION: Physicians should be concerned about the possibility of metastasis during long-term follow-up of high-risk patients and consider salvage treatment.

Effect of bowel preparation completion time on bowel cleansing efficacy: Prospective randomized controlled trial of different bowel preparation completion times precolonoscopy.

OBJECTIVES: The elapse time between the completion of bowel cleansing and colonoscopy is one of the important factors for proper bowel cleansing. Although several studies have reported that a short time interval resulted in a favorable bowel cleansing, no randomized controlled trial (RCT) has been conducted to determine the effect of the elapse time. Consequently, we performed an RCT to investigate the efficacy of bowel preparation of participants who underwent colonoscopy according to the different time intervals between the completion of bowel preparation and colonoscopy. METHODS: In this single-center RCT, study participants were randomized to complete bowel preparation either 2-4 h or 4-8 h before colonoscopy. The primary end-point was successful bowel preparation, rated using the Boston Bowel Preparation Scale (BBPS). RESULTS: A total of 504 individuals were included (2-4 h, 255; 4-8 h, 249). The rate of successful bowel preparation in the 2-4 h group showed noninferiority compared with that of the 4-8 h group (97.6% vs. 95.2%; rate difference, 2.5% [-0.8% to 5.7%]; Pfor noninferiority < 0.001, Pfor superiority = 0.136). The rate for perfect cleansing (a BBPS score of 9) was higher in the 2-4 h group (56.5% vs. 39.8%, P < 0.001). CONCLUSION: When bowel cleansing was finished 2-4 h before the start of colonoscopy, the overall bowel cleansing was noninferior, and perfect cleansing was superior, compared to that when cleansing was finished 4-8 h before colonoscopy.

Rescue technique for self-expandable metallic stent placement using ultrathin endoscope after failure of the conventional method in patients with malignant colon obstruction: a multicenter retrospective study.

BACKGROUND AND AIMS: Self-expandable metallic stents (SEMS) can be used to treat malignant colorectal obstruction (MCO). Guidewire insertion to the proximal site of MCO is the most important step for SEMS placement. However, some patients cannot undergo guidewire insertion because of total obstruction or location at anatomically challenging areas. We report a guidewire insertion technique using an ultrathin endoscope (UTE) in patients with MCO in whom conventional SEMS insertion failed. METHODS: This study was a retrospective cohort study conducted at three academic centers in Korea. The medical records of 956 consecutive patients who underwent SEMS placement during 2012-2021 were analyzed. After failing guidewire insertion using a colonoscope, a UTE was inserted. Guidewire insertion was done through the working channel of the UTE. Following guidewire insertion, the endoscope was removed from the patient. While removing the endoscope, the guidewire was advanced to be located at the originally inserted site. Then, the colonoscope was inserted over the guidewire, and SEMS was replaced. RESULTS: Conventional SEMS insertion failed in 75 patients. Of these, guidewire insertion using a UTE was tried in 59 patients. The rate of technical success was 91.5% (54/59). Considering all patients, the overall technical success rate of SEMS placement was 97.8% (935/956). This technique increased the technical success rate by 5.6% among the total cohort. CONCLUSIONS: The UTE facilitated guidewire insertion and enhanced the overall success rate for SEMS placement. In addition, this technique can be used as a rescue method when guidewire insertion fails using a colonoscope.

Combination of Enhanced Instructions Improve Quality of Bowel Preparation: A Prospective, Colonoscopist-Blinded, Randomized, Controlled Study.

BACKGROUND: Appropriate bowel preparation is highly important for the efficacy of colonoscopy; however, up to one-third of patients do not accomplish adequate bowel preparation. OBJECTIVE: We investigated the impact of the combination of enhanced instruction on the quality of bowel preparation and its impact on clinically relevant outcomes. DESIGN: This was a colonoscopist-blinded, prospective, randomized trial. SETTINGS: All patients received regular instructions for bowel preparation. Patients were randomly assigned to the control, telephone reeducation, and combined enhanced instruction groups. PATIENTS: Outpatients aged 19 to 75 years scheduled to undergo colonoscopy were included. MAIN OUTCOME MEASURES: The main outcome was adequate bowel preparation rate. RESULTS: A total of 311 patients were randomly assigned to the combined enhanced instruction (n = 104), telephone reeducation (n = 101), and control groups (n = 106). An intention-to-treat analysis showed that the adequate bowel preparation rate was higher in the combined enhanced instruction group than in the telephone reeducation and control groups (92.3% vs 82.2% vs 76.4%, p = 0.007). The rate of compliance with the instructions was significantly higher in the combined enhanced instruction group than in the telephone reeducation and control groups. Method of education was associated with proper bowel preparation (adjusted OR 17.46; p < 0.001 for combined enhanced instruction relative to control). LIMITATIONS: This was a single-center study conducted in Korea. CONCLUSIONS: Combined enhanced instruction as an adjunct to regular instructions much improved the quality of bowel preparation and patients' adherence to the preparation instructions. The combined enhanced instruction method could be the best option for bowel preparation instruction. See Video Abstract at http://links.lww.com/DCR/B673. LA COMBINACIN DE INSTRUCCIONES MEJORADAS, INCREMENTA LA CALIDAD DE LA PREPARACIN INTESTINAL ESTUDIO PROSPECTIVO, CONTROLADO, ALEATORIO Y CIEGO PARA EL COLONOSCOPISTA: ANTECEDENTES:La preparación adecuada del intestino es muy importante para la eficacia de la colonoscopia; sin embargo, hasta un tercio de los pacientes no logran buenos resutlados.OBJETIVO:Investigar el impacto de la combinación de instrucciónes claras en la calidad de la preparación intestinal y su impacto en los resultados clínicos.DISEÑO:Trabajo aleatorio, prospectivo y ciego para el colonoscopista.AJUSTES:Los pacientes recibieron instrucciones periódicas para la preparación intestinal. Fueron asignados aleatoriamente al grupo control, educación telefónica y de instrucción mejoradas.PACIENTES:Se incluyeron pacientes ambulatorios de 19 a 75 años programados para ser sometidos a colonoscopia.PRINCIPALES MEDIDAS DE RESULTADO:El principal resultado fue una adecuada preparación intestinal.RESULTADOS:Un total de 311 pacientes fueron asignados al azar a la instrucción mejorada combinada (n = 104), reeducación telefónica (n = 101) y grupo de control (n = 106). El análisis estadístico mostró que la tasa de preparación intestinal adecuada fue mayor en el grupo combinado de instrucción mejorada que en los grupos de reeducación telefónica y control (92,3% vs 82,2% vs 76,4%, p = 0,007). La tasa de cumplimiento de las instrucciones fue significativamente mayor en el grupo de instrucción mejorada combinada que en los otros. El método de educación se asoció con una preparación intestinal adecuada (razón de posibilidades ajustada de 17,46; p <0,001 para la instrucción mejorada combinada en relación con el control.LIMITACIONES:Estudio en un solo centro realizado en Corea.CONCLUSIONES:La instrucción mejorada combinada como complemento de las instrucciones regulares mejoró mucho la calidad de la preparación intestinal y la adherencia de los pacientes a las instrucciones de preparación. El método de instrucción mejorado combinado podría ser la mejor opción para la instrucción de preparación intestinal. Consulte Video Resumen en http://links.lww.com/DCR/B673.

Comparison of 2 L Polyethylene Glycol Plus Ascorbic Acid and 4 L Polyethylene Glycol in Elderly Patients Aged 60-79: A Prospective Randomized Study.

BACKGROUND: The bowel-cleansing efficacy and safety of 2 L polyethylene glycol (PEG) with ascorbic acid (2L PEG + Asc) has rarely been studied in the elderly population. In this randomized trial, we compared the bowel cleanliness, safety, and tolerability of 2L PEG + Asc with those of 4 L PEG in an elderly population aged 60-79. METHODS: Study participants were randomized either to 2L PEG + Asc or 4L PEG. The primary endpoint was the success rate of bowel preparation, using the Boston Bowel Preparation Scale. Before colonoscopy, all participants were questioned about adverse events and tolerability regarding purgative ingestion. RESULTS: A total of 347 individuals were enrolled (2L PEG + Asc, 174; 4L PEG, 173). Mean age in the 2L PEG + Asc and the 4L PEG was 69.3 ± 5.6 and 69.3 ± 5.0, respectively (P = 0.917). The rate for successful bowel cleansing was comparable between the 2L PEG + Asc (92%) and the 4L PEG (96%, P = 0.118). Total ingested liquid including purgative and water was lower in the 2L PEG + Asc group (2.9 L) than in the 4L PEG group (4.2 L, P < 0.001). The tolerability of purgative was superior in the 2L PEG + Asc (overall satisfaction, P < 0.001; willingness to reuse, P < 0.001). There were no serious adverse events during the trial. CONCLUSIONS: The bowel-cleansing efficacy of 2L PEG + Asc was comparable to that of 4L PEG. Tolerability was superior in the 2L PEG + Asc group. For older people, 2L PEG + Asc is an efficacious and safe bowel cleanser. (Clinical trial registration number: KCT0004123).

Prediction model for curative endoscopic submucosal dissection of undifferentiated-type early gastric cancer.

BACKGROUND: Endoscopic submucosal dissection (ESD) is an effective treatment for early gastric cancer (EGC); however, its curative resection rate is low for undifferentiated-type EGC. We developed and externally validated a prediction model for curative ESD of undifferentiated-type EGC. METHODS: In this cross-sectional study, we included 448 patients who underwent ESD for undifferentiated-type EGC at 18 hospitals in Korea between 2005 and 2015 in the development cohort and 1342 patients who underwent surgery at two hospitals in the validation cohort. A prediction model was developed using the logistic regression model. RESULTS: Endoscopic tumor size 1-2 cm (odds ratio [OR], 2.40; 95% confidence interval [CI] 1.54-3.73), tumor size > 2 cm (OR, 14.00; 95% CI 6.81-28.77), and proximal tumor location from the lower to upper third of the stomach (OR, 1.45; 95% CI 1.03-2.04) were independent predictors of non-curative ESD. A six-score prediction model was developed by assigning points to endoscopic tumor size > 2 cm (five points), tumor size 1-2 cm (two points), upper third location (two points), and middle third location (one point). The rate of curative ESD ranged from 70.6% (score 0) to 11.6% (score 5) with an area under the receiver operating characteristic curve (AUC) of 0.720 (95% CI 0.673-0.766). The model also showed good performance in the validation cohort (AUC, 0.775; 95% CI 0.748-0.803). CONCLUSIONS: This six-score prediction model may help in predicting curative ESD and making informed decisions about the treatment selection between ESD and surgery for undifferentiated-type EGC.

Long-term outcomes of endoscopic resection followed by additional surgery after non-curative resection in undifferentiated-type early gastric cancer: a nationwide multi-center study.

BACKGROUND: Undifferentiated-type early gastric cancer (UD EGC) shows lower curative resection rates after endoscopic submucosal dissection (ESD). Additional surgery is recommended after non-curative resection. We evaluated the long-term outcomes of ESD followed by additional surgery after non-curative resection in UD EGC compared to those for surgery as initial treatment. METHODS: We reviewed 1139 UD EGC patients who underwent ESD at 18 hospitals and 1956 patients who underwent surgery at two hospitals between February 2005 and May 2015. We enrolled 636 patients with non-curative ESD and 1429 surgery subjects beyond the curative ESD criteria. Among them, 133 patients with additional surgery after ESD (ESD + OP group) and 252 patients without additional surgery (ESD-only group) were matched 1:1 using propensity scores to patients with surgery as initial treatment (surgery group). Overall survival (OS) and recurrence-free survival (RFS) were compared. RESULTS: Signet ring cell carcinoma and poorly differentiated adenocarcinoma (PDA) were observed in 939 and 1126 cases, respectively. OS was significantly longer in the surgery group than in the ESD + OP group, especially for PDA. However, RFS was shorter in the ESD-only group than those in the ESD + OP and surgery groups. RFS did not differ significantly between the ESD + OP and surgery groups. Compared to the surgery group, the ESD-only and ESD + OP groups had an overall hazard ratio for RFS of 3.58 (95% confidence interval 1.44-8.88) and 0.46 (0.10-2.20), respectively. CONCLUSIONS: ESD followed by additional surgery after non-curative resection showed comparable cancer-specific outcomes to initial surgery in UD EGC.

Effect of prophylactic clip application for the prevention of postpolypectomy bleeding of large pedunculated colonic polyps: a randomized controlled trial.

BACKGROUND AND AIMS: Prophylactic application of a hemoclip has been suggested as an alternative to the use of an endoloop for the prevention of postpolypectomy bleeding (PPB) when resecting large, pedunculated colorectal polyps. Therefore, this multicenter, randomized controlled trial investigated the efficacy of prophylactic hemoclip application to reduce PPB during the resection of large pedunculated polyps. METHODS: Large pedunculated polyps (≥10 mm in head diameter) were eligible for inclusion. Polyps were randomized into a study arm (where clips were applied before resection) and a control arm (without pretreatment). The primary outcome was the rate of PPB in each group. PPB included immediate PPB (IPPB) and delayed PPB (DPPB). IPPB was defined as blood oozing (≥1 minute) or active spurting occurring immediately after polyp resection. DPPB was defined as rectal bleeding, occurring after completion of the colonoscopy. RESULTS: In total, 238 polyps from 204 patients were randomized into the clip arm (119 polyps) or the control arm (119 polyps). Overall bleeding adverse events were observed in 20 cases (IPPB, 16; DPPB, 4). The rate of overall PPB, IPPB, and DPPB was 8.4%, 6.7%, and 1.7%, respectively, for all polyps. The rate of overall PPB (clip 4.2% vs control 12.6%, P = .033) and IPPB (clip 2.5% vs control 10.9%, P = .017) was significantly lower in the clip arm than the control arm. CONCLUSIONS: Prophylactic clipping before resecting large pedunculated polyps can reduce overall PPB and IPPB compared with no prior treatment. Therefore, prophylactic clipping may be considered before resection of large pedunculated polyps. (Clinical trial registration number: NCT02156193.).

Clinical outcomes of endoscopic resection for undifferentiated intramucosal early gastric cancer larger than 2 cm.

BACKGROUND: This study investigated the long-term clinical outcomes of endoscopic resection (ER) for undifferentiated-type (UD) early gastric cancer (EGC), with tumor size > 2 cm as the only non-curative factor. METHODS: From among 1123 patients who underwent ER for UD EGC at 18 tertiary hospitals in Korea between 2005 and 2014, we identified 216 patients with UD intramucosal EGC > 2 cm, which was completely resected, with negative resection margins, and absence of ulceration and lymphovascular invasion. The patients were divided into the additional surgery (n = 40) or observation (n = 176) groups, according to post-ER management and were followed up for a median duration of 59 months for recurrence and 90 months for overall survival. RESULTS: Lymph node (LN) or distant metastasis or cancer-related mortality was not observed in the surgery group. In the observation group, two (1.1%) patients developed LN or distant metastasis with a 5-year cumulative risk of 0.7%, and one (0.6%) patient died of gastric cancer. The 5- and 8-year overall survival rates were 94.1% and 89.9%, respectively, in the observation group and 100.0% and 95.2%, respectively, in the surgery group (log-rank P = 0.159). Cox regression analysis did not reveal an association between the observation group and increased mortality. CONCLUSION: The risk of LN or distant metastasis was not negligible, but as low as 1% for patients undergoing non-curative ER for UD EGC, with tumor size > 2 cm as the only non-curative factor. Close observation may be an alternative to surgery, especially for older patients or those with poor physical status.

Comparison between endoscopic submucosal resection and surgery for the curative resection of undifferentiated-type early gastric cancer within expanded indications: a nationwide multi-center study.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD EGC) has debate due to the risk of lymph node metastasis. We investigated the outcomes of ESD compared to those of surgery for the UD EGC within expanded indication. METHODS: We reviewed 971 UD EGC patients performed ESD across 18 hospitals in Korea and 1812 patients who underwent surgical resection in two hospitals between February 2005 and May 2015. Of these cases, we enrolled a curative resected ESD group of 328 patients and surgery group of 383 cases within an expanded indication. Overall outcomes and one-to-one propensity score-matched (218 ESD group vs 218 surgery group cases) outcomes for these two groups were analyzed. RESULTS: Over the 75.6 month median follow-up period for the 711 enrolled cases, recurrences occurred in 22 patients (6.7%) in the ESD group but not in the surgery group. Overall survival (OS) was higher in the surgery group (p = 0.0316) in all cases, but there was no significant difference after propensity score matching (p = 0.069). According to the histologic type in propensity score matching, the OS of signet ring cell carcinoma and poorly differentiated carcinoma patients did not differ between the ESD and surgery groups (p = 0.1189 and p = 0.3087, respectively). In the surgery group involving expanded criteria, lymph node metastasis was found in six cases (1.56%). CONCLUSIONS: Although ESD shows comparable outcomes to surgery for the UD EGC within expanded indications, appropriate patient selection is needed for the ESD due to the possibility of lymph node metastasis.

Risk factors of lymph node metastasis after non-curative endoscopic resection of undifferentiated-type early gastric cancer.

BACKGROUND: This study aimed to investigate risk factors for lymph node (LN) or distant metastasis after non-curative endoscopic resection (ER) of undifferentiated-type early gastric cancer (EGC). METHODS: Of 1124 patients who underwent ER for undifferentiated-type gastric cancer at 18 tertiary hospitals across six geographic areas in Korea between 2005 and 2014, 634 with non-curative ER beyond the expanded criteria were retrospectively enrolled. According to the treatment after ER, patients were divided into additional surgery (n = 270) and follow-up (n = 364) groups. The median follow-up duration was 59 months for recurrence and 84 months for mortality. RESULTS: LN metastasis was found in 6.7% (18/270) of patients at surgery. Ulcer [odds ratio (OR) 3.83; 95% confidence interval (CI) 1.21-12.13; p = 0.022] and submucosal invasion (OR 10.35; 95% CI 1.35-79.48; p = 0.025) were independent risk factors. In the follow-up group, seven patients (1.9%) developed LN or distant recurrence. Ulcer [hazard ratio (HR) 7.60; 95% CI 1.39-35.74; p = 0.018], LVI (HR 6.80; 95% CI 1.07-42.99; p = 0.042), and positive vertical margin (HR 6.71; 95% CI 1.28-35.19; p = 0.024) were independent risk factors. In the overall cohort, LN metastasis rates were 9.6% in patients with two or more risk factors and 1.2% in those with no or one risk factor. CONCLUSIONS: LVI, ulcer, submucosal invasion, and positive vertical margin are independently associated with LN or distant metastasis after non-curative ER of undifferentiated-type EGC. Surgical resection is strongly recommended for patients with two or more risk factors.

Comparison of adenoma detection by colonoscopy between polypectomy performed during both insertion and withdrawal versus during withdrawal only: a multicenter, randomized, controlled trial.

BACKGROUND AND AIM: In standard colonoscopy, the colonoscope is inserted into the cecum, and inspection of the colonic mucosa and polypectomy are performed during withdrawal. The colon configuration can differ between the insertion and withdrawal phases, and some polyps found in the insertion phase can be missed during withdrawal. A few single-center studies investigated whether detection of polyps during the insertion phase affects the adenoma detection rate (ADR). However, the effectiveness of this strategy is unknown because of conflicting results. We aimed to determine whether polypectomy together with careful inspection during insertion increases the ADR compared with standard colonoscopy. METHODS: A randomized, controlled, multicenter trial was conducted at three university hospitals. Patients aged 50 to 80 years were randomly assigned to the study group or control group. For patients in the study group, polypectomy was performed together with careful inspection during both colonoscope insertion and withdrawal. In the control group, polyps were inspected and removed only during colonoscope withdrawal. The primary endpoint was the ADR, which was defined as the percentage of patients with ≥ 1 adenoma. RESULTS: A total of 1142 patients were enrolled (study group, n = 571; control group, n = 571). The ADR was similar in the 2 groups (study group, 44.1%; control group, 43.1%; P = 0.72). In the control group, 12 polyps that had been detected during colonoscope insertion were not found during withdrawal (polyp miss rate: 2.1%, 12/571). CONCLUSION: Polypectomy and careful inspection during both colonoscope insertion and withdrawal did not improve the overall ADR compared with standard colonoscopy (NCT01925833).

Comparison of bowel-cleansing efficacy of split-dose and same-day dose bowel preparation for afternoon colonoscopy in patients with gastrectomy: a prospective randomized study.

BACKGROUND: A split dose (SPD) of purgative is the recommended bowel-preparation method for colonoscopy, although for colonoscopy scheduled for the afternoon, a same-day dose (SDD) of purgative is recommended. However, it has not been determined whether SPD or SDD is better in patients with gastrectomy who are at high risk of suboptimal bowel cleansing. We compared the bowel-cleansing efficacy of SPD and SDD regimens in patients with gastrectomy who underwent colonoscopy in the afternoon. METHODS: This was a prospective, randomized, assessor-blinded study. For the SDD group, polyethylene glycol (PEG) was ingested on the day of colonoscopy starting at 7 AM. In the SPD group, 2 L PEG was ingested at 9 PM the day before colonoscopy, and the remaining 2 L from 10 AM on the day of colonoscopy. Colonoscopy was performed from 1:30 PM. Before colonoscopy, the participants completed questionnaires asking about bowel-movement kinetics, adverse events, tolerability, overall satisfaction, and willingness to reuse the protocol. The bowel-cleansing efficacy was assessed using the Boston Bowel Preparation Scale. RESULTS: A total of 193 subjects were included (SDD, 95; SPD, 98). The rate of successful bowel cleansing was comparable between the two groups (SDD, 92.6% vs. SPD, 95.9%; P = 0.37). The incidence of adverse events (nausea, vomiting, bloating, abdominal pain, and dizziness/headache) was also comparable between the two groups. However, sleep disturbance was higher in the SPD group (SDD, 10.5% vs. SPD, 25.5%; P = 0.01). Tolerability did not differ between the SDD and SPD groups (satisfaction, P = 0.11; willingness to reuse, P = 0.29). CONCLUSIONS: The bowel-cleansing efficacy, safety profile, and patient tolerability of SDD and SPD were comparable. Both SDD and SPD regimens are feasible bowel-preparation methods for patients with gastrectomy who undergo colonoscopy in the afternoon. TRIAL REGISTRATION: Clinical trial registration number: KCT0002699.

Comparison of Bowel Cleansing Efficacy, Safety, Bowel Movement Kinetics, and Patient Tolerability of Same-Day and Split-Dose Bowel Preparation Using 4 L of Polyethylene Glycol: A Prospective Randomized Study.

BACKGROUND: Split-dose bowel preparation is recommended for morning colonoscopy, although a same-day dose regimen is an alternative for afternoon colonoscopy. Same-day preparation for morning colonoscopy has rarely been evaluated. OBJECTIVE: We compared the bowel cleansing efficacy, bowel movement kinetics, safety profile, and patient tolerability of split-dose and same-day preparation using 4-L polyethylene glycol. DESIGN: This was a prospective, randomized, assessor-blinded study. SETTINGS: This study was performed at a tertiary center in Korea. PATIENTS: Study subjects were randomly assigned to the same-day or split-dose groups. For the same-day dose group, 4 L of polyethylene glycol were ingested on the day of colonoscopy starting at 5:00 AM for morning colonoscopy or 7:00 AM for afternoon colonoscopy. In the split-dose group, 2 L of polyethylene glycol were ingested at 9:00 PM the day before colonoscopy, and the remaining 2 L from 7:00 AM for morning colonoscopy or from 10:00 AM for afternoon colonoscopy. Colonoscopy was performed from 10:00 AM. MAIN OUTCOME MEASURES: The efficacy of bowel cleansing was evaluated using the Boston bowel preparation scale. The participants completed questionnaires asking about adverse events, bowel movement kinetics, and tolerability of the preparation before colonoscopy. RESULTS: A total of 339 subjects were included (same-day dose = 172; split dose = 167). One subject in each group did not undergo colonoscopy. The rate of successful cleansing did not differ between the groups (same-day dose = 98.8% vs split dose = 98.2%; p = 0.681). There were no instances of hemodynamic instability or aspiration in either group. Tolerability, including overall satisfaction and willingness to reuse, were comparable between the groups. LIMITATIONS: This was a single-center study. CONCLUSIONS: The bowel cleansing efficacy, safety profile, and tolerability of same-day dosing with polyethylene glycol were comparable with those of split dose. Therefore, same-day dosing with 4 L of polyethylene glycol is a feasible bowel preparation method. See Video Abstract at http://links.lww.com/DCR/B44. COMPARACIÓN DE LA EFICACIA DE LA LIMPIEZA INTESTINAL, LA SEGURIDAD, LA CINÉTICA DEL MOVIMIENTO INTESTINAL Y LA TOLERABILIDAD DEL PACIENTE DE LA PREPARACIÓN INTESTINAL EN EL MISMO DÍA Y EN DOSIS DIVIDIDAS UTILIZANDO 4 L DE POLIETILENGLICOL: UN ESTUDIO PROSPECTIVO ALEATORIZADO: Se recomienda la preparación del intestino en dosis divididas para la colonoscopia de la mañana, aunque un régimen de una sola dosis el mismo día es una alternativa para la colonoscopia en la tarde. La preparación de una sola dosis el mismo día para la colonoscopia matutina rara vez se ha evaluado.Comparamos la eficacia de la limpieza intestinal, la cinética del movimiento intestinal, el perfil de seguridad y la tolerabilidad del paciente de la dosis dividida y la preparación el mismo día utilizando 4 L de polietilenglicol.Este fue un estudio prospectivo, aleatorizado, cegado por el evaluador.Este estudio se realizó en un centro terciario en Corea.Los sujetos del estudio fueron asignados aleatoriamente a el grupo de una dosis en el mismo día o al grupo de dosis dividida. Para el grupo de dosis del mismo día, se ingirieron 4 L de polietilenglicol el día de la colonoscopia a partir de las 5 a.m. para la colonoscopia de la mañana o las 7 a.m. para la colonoscopia de la tarde. En el grupo de dosis dividida, se ingirieron 2 L de polietilenglicol a las 9 p.m. el día anterior a la colonoscopia, y los otros 2 L restantes a partir de las 7 a.m. para la colonoscopia de la mañana o desde las 10 a.m. para la colonoscopia de la tarde. La colonoscopia se realizó a partir de las 10 a.m.La eficacia de la limpieza intestinal se evaluó mediante la escala de preparación intestinal de Boston. Los participantes completaron cuestionarios preguntando sobre los eventos adversos, la cinética del movimiento intestinal y la tolerabilidad de la preparación antes de la colonoscopia.Se incluyeron un total de 339 sujetos (dosis el mismo día, 172; dosis dividida, 167). Un sujeto en cada grupo no se sometió a colonoscopia. La tasa de limpieza exitosa no difirió entre los grupos (dosis el mismo día, 98.8% versus dosis dividida, 98.2%; p = 0.681). No hubo casos de inestabilidad hemodinámica o aspiración en ninguno de los grupos. La tolerabilidad, incluida la satisfacción general y la voluntad de reutilización, fueron comparables entre los grupos.Este fue un estudio de centro único.La eficacia de la limpieza intestinal, el perfil de seguridad y la tolerabilidad de la dosificación en el mismo día con polietilenglicol fueron comparables con los de la dosis dividida. Por lo tanto, la dosificación en el mismo día con 4 L de polietilenglicol es un método factible de preparación intestinal. Vea el video del resumen en http://links.lww.com/DCR/B44.

Risk factors for peritonitis in patients on continuous ambulatory peritoneal dialysis who undergo colonoscopy: a retrospective multicentre study.

BACKGROUND: Colonoscopy is associated with a risk of peritonitis in patients on peritoneal dialysis. However, no study has yet described the risk factors in play. METHODS: This was a retrospective multicentre study. The medical records of patients on continuous ambulatory peritoneal dialysis (CAPD) who underwent colonoscopy from January 2003 to December 2012 were analysed. We recorded demographic characteristics, colonoscopic factors, use of prophylactic antibiotics, and development of peritonitis. Colonoscopy-related peritonitis was defined as peritonitis developing within 1 week after colonoscopy. Demographic and clinical characteristics were compared between patients who did and those who did not develop peritonitis. RESULTS: During the study period, 236 patients on CAPD underwent colonoscopy, of whom 9 (3.8%) developed peritonitis. The rates of polypectomy/endoscopic mucosal resection were significantly higher in the peritonitis group than in the no peritonitis group (66.7 vs. 23.4%, p = 0.009). Prophylactic antibiotics were prescribed before colonoscopy in 65 patients; none developed peritonitis. No patient who developed peritonitis received prophylactic antibiotics (p = 0.067). CONCLUSIONS: Advanced procedures including polypectomy or endoscopic mucosal resection increase colonoscopy-related peritonitis in patients on CAPD. Randomized controlled trials to investigate whether prophylactic antibiotics are needed to prevent peritonitis in all CAPD patients are warranted.

A survey of current practices in post-polypectomy surveillance in Korea.

BACKGROUND/AIMS: We investigated the clinical practice patterns of post-polypectomy colonoscopic surveillance among Korean endoscopists. METHODS: In a web-based survey conducted between September and November 2021, participants were asked about their preferred surveillance intervals and the patient age at which surveillance was discontinued. Adherence to the recent guidelines of the U.S. Multi-Society Task Force on Colorectal Cancer (USMSTF) was also analyzed. RESULTS: In total, 196 endoscopists completed the survey. The most preferred first surveillance intervals were: a 5-year interval after the removal of 1-2 tubular adenomas < 10 mm; a 3-year interval after the removal of 3-10 tubular adenomas < 10 mm, adenomas ≥ 10 mm, tubulovillous or villous adenomas, ≤ 20 hyperplastic polyps < 10 mm, 1-4 sessile serrated lesions (SSLs) < 10 mm, hyperplastic polyps or SSLs ≥ 10 mm, and traditional serrated adenomas; and a 1-year interval after the removal of adenomas with highgrade dysplasia, >10 adenomas, 5-10 SSLs, and SSLs with dysplasia. In piecemeal resections of large polyps ( > 20 mm), surveillance colonoscopy was mostly preferred after 1 year for adenomas and 6 months for SSLs. The mean USMSTF guideline adherence rate was 30.7%. The largest proportion of respondents (40.8%-55.1%) discontinued the surveillance at the patient age of 80-84 years. CONCLUSIONS: A significant discrepancy was observed between the preferred post-polypectomy surveillance intervals and recent international guidelines. Individualized measures are required to increase adherence to the guidelines.

Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms.

BACKGROUND: We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC). METHODS: Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses. RESULTS: The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4-2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75-3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72-3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24-8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17-4.76; P < 0.001) were risk factors for overall CRN. CONCLUSIONS: The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.

[Gut Microbiome and Colorectal Cancer].

Colorectal cancer (CRC) is one of the most common cancers in Korea. A majority of CRCs are caused by progressive genomic alterations referred to as the adenoma-carcinoma sequence. The factors that may increase the risk of CRC include obesity and consumption of a high-fat diet, red meat, processed meat, and alcohol. Recently, the role of gut microbiota in the formation, progression and treatment of CRCs has been investigated in depth. An altered gut microbiota can drive carcinogenesis and cause the development of CRC. Studies have also shown the role of gut microbiota in the prevention of CRC and the impact of therapies involving gut microbiota on CRC. Herein, we summarize the current understanding of the role of the gut microbiota in the development of CRC and its therapeutic potential, including the prevention of CRC and in enhancing efficacy of chemotherapy and immunotherapy.

Management of complications related to colorectal endoscopic submucosal dissection.

Compared to endoscopic mucosal resection (EMR), colonoscopic endoscopic submucosal dissection (C-ESD) has the advantages of higher en bloc resection rates and lower recurrence rates of colorectal neoplasms. Therefore, C-ESD is considered an effective treatment method for laterally spread tumors and early colorectal cancer. However, C-ESD is technically more difficult and requires a longer procedure time than EMR. In addition to therapeutic efficacy and procedural difficulty, safety concerns should always be considered when performing C-ESD in clinical practice. Bleeding and perforation are the main adverse events associated with C-ESD and can occur during C-ESD or after the completion of the procedure. Most bleeding associated with C-ESD can be managed endoscopically, even if it occurs during or after the procedure. More recently, most perforations identified during C-ESD can also be managed endoscopically, unless the mural defect is too large to be sutured with endoscopic devices or the patient is hemodynamically unstable. Delayed perforations are quite rare, but they require surgical treatment more frequently than endoscopically identified intraprocedural perforations or radiologically identified immediate postprocedural perforations. Post-ESD coagulation syndrome is a relatively underestimated adverse event, which can mimic localized peritonitis from perforation. Here, we classify and characterize the complications associated with C-ESD and recommend management options for them.

Case of Pseudomembranous Colitis Caused by a Clostridioides difficile Infection Concomitant with Cytomegalovirus colitis Mimicking Ischemic Colitis.

A Clostridioides difficile infection (CDI) is one of the major nosocomial diarrheal diseases. Pseudomembranous colitis (PMC) is a characteristic endoscopic finding of CDI, manifested by white or yellowish plaque covering the colonic mucosa. Ischemic colitis is inflammation of the colon manifested by mucosal denudation and friability. Ischemic colitis is rarely associated with CDI. The treatment response might be delayed when CDI is complicated with other diseases that cause diarrhea. Thus far, reports of CDI concomitant with Cytomegalovirus (CMV) colitis are rare. This paper reports a case of PMC and ischemic colitis associated with CDI and CMV infection. After two weeks of oral vancomycin and intravenous metronidazole, the patient's diarrhea was not improved. Follow-up sigmoidoscopy was performed, and a CMV infection was identified at areas of broad ulceration where ischemic colitis occurred. Finally, the patient was cured with ganciclovir. Follow-up sigmoidoscopy showed an improvement in ischemic colitis.