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.

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.

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.

[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.

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.

Assessment of Fatigue and Associated Factors in Patients with Inflammatory Bowel Disease: A Questionnaire-Based Study.

Although fatigue is common in patients with inflammatory bowel disease (IBD), it often goes unrecognized and untreated. We investigated the degree of fatigue and associated factors in patients with IBD. A multicenter study involving 147 IBD patients was conducted at five academic hospitals from August 2019 to December 2021. Fatigue was evaluated using the validated Korean version of the Multidimensional Fatigue Inventory (MFI-K). Among 97 ulcerative colitis patients and 50 Crohn's disease patients, the mean total MFI-K score was 59.0 ± 5.5, which corresponded to a moderate-to-severe level of fatigue. Moderate-to-severe disease activity was found to be significantly associated with a higher general and physical fatigue subscale MFI-K score compared to remission-to-mild disease activity (17.6 ± 1.7 vs. 16.7 ± 2.0, p = 0.009), while the use of biologics was associated with a lower total MFI-K score (57.3 ± 5.0 vs. 59.5 ± 5.5, p = 0.031). In multiple linear regression, the total MFI-K score was positively correlated with a history of surgery for IBD, while it was negatively correlated with the use of biologics. Depression was positively correlated with the reduced motivation subscale score. The degree of fatigue in patients with IBD was high. Disease activity, the use of biologics, a history of surgery for IBD, and depression were associated with fatigue.

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.

Incidence and risk of pancreatic cancer in patients with chronic pancreatitis: defining the optimal subgroup for surveillance.

We aimed to present the incidence and risk factors for pancreatic cancer in a multicenter retrospective cohort of patients with chronic pancreatitis (CP). Patients with ICD-10 codes for CP (K86.0, K86.1) who underwent abdominal CT or MRI between January 2010 and December 2021 in seven academic hospitals were analyzed. After exclusions, we identified 727 patients with definite CP with a median follow-up of 3.6 years (range 1.0‒12.9). During 3290 person-years of observation, pancreatic cancers were diagnosed in 16 patients (2.20%, 0.49% per year) after a median follow-up of 2.4 years (range 1.4‒6.6), with an age- and sex-standardized incidence ratio of 18.1 (95% CI 10.4‒29.5). The underlying CPs in the 16 pancreatic cancers were classified as chronic obstructive pancreatitis (10, 63%), chronic obstructive and calcifying pancreatitis (4, 25%), chronic calcifying pancreatitis (1, 6%), and autoimmune pancreatitis (1, 6%). Factors associated with pancreatic cancer development included age (HR 4.830, p = 0.006), parenchymal calcification (HR 0.213, p = 0.003), pancreatic duct stricture (HR 2.706, p = 0.048), and serum CA 19‒9 level (HR 3.567, p = 0.014). After adjustment, age over 60 years (HR 4.540, p = 0.009) and serum CA 19‒9 levels greater than 100 U/mL (HR 3.528, p = 0.015) were independent risk factors for pancreatic cancer.

Ischemic colitis complicated by Clostridioides difficile infection treated with fecal microbiota transplantation.

Ischemic colitis is an inflammatory condition of the colon that results from insufficient blood supply commonly caused by enterocolitis, vessel occlusion, or shock. In contrast, pseudomembranous colitis is a clinical manifestation of Clostridioides difficile infection (CDI). Ischemic colitis caused by CDI has rarely been reported. Fecal microbiota transplantation (FMT) is an efficient treatment for refractory or fulminant CDI, and the indications for its use have recently expanded. However, performing FMT in patients with ischemic colitis is challenging because of the risk of perforation. Here, we have presented a case of ischemic colitis caused by CDI that was successfully treated with FMT via sigmoidoscopy.

Recognition and attitudes of Korean physicians toward fecal microbiota transplantation: a survey study.

BACKGROUND/AIMS: Fecal microbiota transplantation (FMT) represents a treatment option for recurrent Clostridioides difficile infection (CDI). Recently, FMT has been investigated in various clinical settings other than CDI. This study examined Korean physicians' recognition of FMT and their attitudes toward this procedure. METHODS: An online questionnaire included questions on indications for FMT, the FMT process, physicians' attitudes toward FMT for the treatment of CDI and non-CDI diseases, and possible concerns. RESULTS: Finally, 107 physicians responded to this survey: 66 (61.7%) had experience of performing FMT, and 86 (80.4%) replied that they were willing to perform FMT for CDI. Two-thirds of physicians (63.6%, n = 68) would perform FMT for recurrent CDI on patients who had at least three recurrences. The most common obstacle to performing FMT for the treatment of CDI was the lack of regulations or guidelines (55.1%, n = 59). Seventy-seven (72.0%) physicians would consider FMT for non- CDI diseases when conventional treatment had failed. The most common obstacle for FMT for the treatment of non-CDI diseases was low treatment efficacy (57.0%, n = 61). CONCLUSION: Two-thirds of Korean physicians had experience of performing FMT, and many performed FMT for recurrent CDI. The results of this study will prove useful to researchers and practitioners in FMT in Korea.

Reliability and Validity of Korean Version of Crohn's and Ulcerative Colitis Questionnaire-8.

Background: Patients with inflammatory bowel disease (IBD) have a decreased quality of life (QoL), the improvement of which is a treatment goal. The CUCQ-8 is a verified simple and effective QoL measurement tool. We validated the Korean version of CUCQ-8 with the approval of its developer. Methods: We investigated the correlation between the Korean version of CUCQ-8 and the IBDQ-32 in patients with IBD. Results: In all, 147 subjects (male, 97 (66.0%); female, 50 (34.0%); mean age 36.2 ± 13.5 years) were analyzed. Cronbach's alpha coefficient of the CUCQ-8 was 0.833, indicating very high internal consistency. The Korean version of the CUCQ-8 showed a significant correlation with the IBDQ-32 and its subscales (correlation coefficient, >0.75). Conclusions: The Korean version of the CUCQ-8 has high reliability and construct validity and can be used to evaluate the QoL of patients with IBD.

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).

Clinical Practice Guidelines for Fecal Microbiota Transplantation in Korea.

Fecal microbiota transplantation (FMT) is a highly efficacious and safe modality for the treatment of recurrent or refractory Clostridioides difficile infection (CDI), with overall success rates of 90%. Thus, FMT has been widely used for 10 years. The incidence and clinical characteristics of CDI, the main indication for FMT, differ between countries. To date, several guidelines have been published. However, most of them were published in Western countries and therefore cannot represent the Korean national healthcare systems. One of the barriers to performing FMT is a lack of national guidelines. Accordingly, multidisciplinary experts in this field have developed practical guidelines for FMT. The purpose of these guidelines is to aid physicians performing FMT, which can be adapted to treat CDI and other conditions.

Analysis of symptomatic recurrences of common bile ducts stones after endoscopic removal: Factors related to early or multiple recurrences.

ABSTRACT: Early or multiple recurrences of symptomatic common bile duct (CBD) stones are troublesome late complications after endoscopic stone removal. We aimed to determine the factors related to early or multiple recurrences of CBD stones.We retrospectively analyzed patients who underwent endoscopic CBD stone extraction in a single institute between January 2006 and December 2015. Patients were divided into 2 groups according to the number and interval of CBD stone recurrences: single versus multiple (≥2) and early (<1.5 years) versus late (≥1.5 years) recurrence.After exclusion, 78 patients were enrolled and followed up for a median of 1974 (IQR: 938-3239) days. Twenty-seven (34.6%) patients experienced multiple recurrences (≥2 times), and 26 (33.3%) patients experienced early first recurrence (<1.5 years). In the multivariate analysis, CBD angulation was independently related to multiple CBD stone recurrence (OR: 4.689, P = .016), and endoscopic papillary large balloon dilation was independently related to late first CBD stone recurrence (OR: 3.783, P = .025). The mean CBD angles were more angulated with increasing instances of recurrence (0, 1, 2, 3, and ≥4 times) with corresponding values of 150.3°, 148.2°, 143.6°, 142.2°, and 126.7°, respectively (P = .011). The period between the initial treatment and first recurrence was significantly longer than the period between the first and second recurrence (P = .048).In conclusion, greater CBD angulation is associated with the increased number of CBD stone recurrence, and EPLBD delays the recurrence of CBD stones after endoscopic CBD stone removal.

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.

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.

Long-term Outcomes of Undifferentiated-Type Early Gastric Cancer with Positive Horizontal Margins after Endoscopic Resection.

Background/Aims: This study examined the long-term outcomes of undifferentiated-type early gastric cancer (UD EGC) with positive horizontal margins (HMs) after endoscopic resection (ER) and compared them between additional surgery and nonsurgical management. Methods: From 2005 to 2015, a total of 1,124 patients with UD EGC underwent ER at 18 tertiary hospitals in Korea. Of them, 92 patients with positive HMs as the only noncurative factor (n=25) or with both positive HMs and tumor size >2 cm (n=67) were included. These patients underwent additional surgery (n=40), underwent additional endoscopic treatment (n=6), or were followed up without further treatment (n=46). Results: No lymph node (LN) metastasis was found in patients who underwent additional surgery. During a median follow-up of 57.7 months (interquartile range, 27.6 to 68.8 months), no LN or distant metastases or gastric cancer-related deaths occurred in the overall cohort. At baseline, the residual cancer rate was 57.8% (26/45) after additional surgery or ER. The 5-year local recurrence rate was 33.6% among patients who were followed up without additional treatment. The 5-year overall survival rates were 95.0% and 87.8% after additional surgery and nonsurgical management (endoscopic treatment or close follow-up), respectively (log-rank p=0.224). In the multivariate Cox regression analysis, nonsurgical management was not associated with an increased risk of mortality. Conclusions: UD EGC with positive HMs after ER may have favorable long-term outcomes and a very low risk of LN metastasis. Nonsurgical management may be suggested as an alternative, particularly for patients with old age or chronic illness.