Endoscopic mucosal resection and endoscopic submucosal dissection of large colonic polyps

Substratifying the risk of covert malignancy in significant rectal polyps: Outcomes from a specialist multidisciplinary team (MDT)

AIM

A treatment strategy for patients with a significant polyp or early colon cancer (SPECC) of the rectum presents a challenge due to the significant rate of covert malignancy and lack of standardized assessment. For this reason, NICE recommends multidisciplinary meetings to improve outcomes. The primary aim of the present study was to report the performance of our specialist early rectal cancer (SERC) multidisciplinary team (MDT) in correctly substratifying the risk of cancer and to discuss the limitations of staging investigations in those patients with "poor outcomes".

METHOD

This was a retrospective review of patients referred to our SERC MDT from 2014 to 2019. Lesions were assigned by the MDT to three pre-resection categories (low, intermediate, high) according to the risk of covert malignancy. Resection method and final histology were compared to the pre-resection categories.

RESULTS

Of 350 SPECC lesions, 174 were assessed as low-risk, 108 intermediate-risk and 68 high-risk. The cancer incidence was 4.8%, 8.3% and 53%, respectively (15.5% overall). Eight lesions were categorized as low-risk but following piecemeal resection were found to be malignant. Five lesions, three of which were categorized as high-risk, were ultimately benign following conventional surgery. One pT1sm1 cancer, removed by anterior resection, may have been treated by local excision.

CONCLUSION

A total of 83% of malignant polyps were triaged to an en bloc resection technique and surgical resection avoided for nearly all benign lesions. However, 12 patients from this cohort were deemed to have a poor outcome because of miscategorization. Further comparative research is needed to establish the optimum strategy for rectal SPECC lesion assessment.

ORIGINALITY STATEMENT

There is currently no consensus for staging significant polyps of the rectum. This paper reports the effectiveness of a specialist early rectal cancer MDT to correctly risk-stratify significant rectal polyps. It underscores the importance of accurate categorization for treatment decision-making, while acknowledging the limitations of current staging modalities.

Synergistic Drug-Loaded Shear-Thinning Star Polymer Hydrogel Facilitates Gastrointestinal Lesion Resection and Promotes Wound Healing

Easy injection, long-lasting barrier, and drug loading are the critical properties of submucosal injection materials for endoscopic surgery. However, conventional injectable polymers face challenges in simultaneously attaining these properties due to the inherent conflict between injectability and in situ stability. Here, a multi-arm star polymer hydrogel (denoted as βCP hydrogel) with long-lasting submucosal barrier (exceeding 120 min), rapid hemostasis, and sustained antibacterial properties is successfully developed by grafting poly(oligo(ethylene glycol) methyl ether methacrylate) (PEGMA) side-chains from β-CD via atom transfer radical polymerization (ATRP). During the onset of shearing, βCP hydrogel experiences the unwinding of polymer side-chains between neighboring star polymers, which facilitates the process of endoscopic injectability. After submucosal injection, βCP hydrogel undergoes the winding of polymer side-chains, thereby establishing a long-lasting barrier cushion. Meanwhile, owing to its distinctive structures with a hydrophobic inner cavity and an outer layer of hydrophilic polymer side-chains, βCP hydrogel enables simultaneous loading and on-demand release of diverse categories of drugs. This unique performance can adapt to the diverse demands during different stages of wound healing in a porcine endoscopic surgery model. These results indicate an appealing prospect for new application of star polymers as a good submucosal injection material in endoscopic treatments.

Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Treatment of rectosigmoid endometriosis by laparoscopic reverse submucosal dissection (LRSD): The Sydney partial thickness discoid excision technique

BACKGROUND

Laparoscopic reverse submucosal dissection (LRSD) is a standardised surgical technique for removal of rectosigmoid endometriosis which optimises the anatomical dissection plane for excision of endometriotic nodules.

AIM

This cohort study assesses the outcomes of the first cohort of women treated by LRSD, for deeply infiltrating rectosigmoid endometriosis.

MATERIALS AND METHODS

Primary outcomes assessed were complication rate as defined by the Clavien-Dindo system, and completion of the planned LRSD. Secondary outcomes include mucosal breach, specimen margin involvement, length of hospital admission, and a comparison of pre-operative and post-operative pain, bowel function and quality of life surveys. These included the Endometriosis Health Profile Questionnaire (EHP-30), the Knowles-Eccersley-Scott Symptom Questionnaire (KESS) and the Wexner scale.

RESULTS

Of 19 patients treated, one required a segmental resection. The median length of hospital admission was two days (range 1-5) and no post-operative complications occurred. Median pain visual analogue scales (scale 0-10) were higher prior to surgery (dysmenorrhoea 9.0, dyspareunia 7.5, dyschezia 9.0, pelvic pain 6.0) compared to post-surgical median scores (dysmenorrhoea 5.0, dyspareunia 4.0, dyschezia 2.0, pelvic pain 4.0) at a median of six months (range 4-32). Quality of life studies suggested improvement following surgery with pre-operative median EHP-30 and KESS scores (EHP-30: 85 (5-106), KESS score 9 (0-20)) higher than post-operative scores (EHP-30: 48.5 (0-80), KESS score: 3 (0-19)).

CONCLUSION

This series highlights the feasibility of LRSD with low associated morbidity as a progression of partial thickness discoid excision (rectal shaving) for the treatment of rectosigmoid deep infiltrating endometriosis.

Precision endoscopy in colorectal polyps' characterization and planning of endoscopic therapy

Precision endoscopy in the management of colorectal polyps and early colorectal cancer has emerged as the standard of care. It includes optical characterization of polyps and estimation of submucosal invasion depth of large nonpedunculated colorectal polyps to select the appropriate endoscopic resection modality. Over time, several imaging modalities have been implemented in endoscopic practice to improve optical performance. Among these, image-enhanced endoscopy systems and magnification endoscopy represent now well-established tools. New advanced technologies, such as endocytoscopy and confocal laser endomicroscopy, have recently shown promising results in predicting the histology of colorectal polyps. In recent years, artificial intelligence has continued to enhance endoscopic performance in the characterization of colorectal polyps, overcoming the limitations of other imaging modes. In this review we retrace the path of precision endoscopy, analyzing the yield of various endoscopic imaging techniques in personalizing management of colorectal polyps and early colorectal cancer.

Combined Endoscopic Robotic Surgery for Complex Colon Polyps

BACKGROUND

Combined endoscopic robotic surgery is a surgical technique that modifies traditional endoscopic laparoscopic surgery with robotic assistance to aid in the removal of complex colonic polyps. This technique has been described in the literature but lacks patient follow-up data.

OBJECTIVE

This study aimed to evaluate the safety and outcomes of combined endoscopic robotic surgery.

DESIGN

A retrospective review of a prospective database.

SETTING

East Jefferson General Hospital, Metairie, Louisiana.

PATIENTS

Ninety-three consecutive patients who underwent combined endoscopic robotic surgery from March 2018 to October 2021 were included in the study.

MAIN OUTCOME MEASURES

Operative time, intraoperative complication, 30-day postoperative complication, hospital length of stay, and follow-up pathology report results were the main outcome measures.

RESULTS

Combined endoscopic robotic surgery was completed in 88 of 93 participants (95%). Among the 88 participants who completed combined endoscopic robotic surgery, the average age was 66 years (SD = 10), BMI was 28.8 kg/m 2 (SD = 6), and history of previous abdominal surgeries was 1 (SD = 1). Median operative time was 72 minutes (range, 31-184 minutes) and polyp size was 40 mm (range, 5-180 mm). The most common polyp locations were the cecum, ascending colon, and transverse colon (31%, 28%, 25%). Pathology mainly demonstrated tubular adenoma (76%). Data on 40 patients who underwent follow-up colonoscopy were available. The average follow-up time was 7 months (range, 3-22 months). One patient (2.5%) had polyp recurrence at the resection site.

LIMITATIONS

Limitations for our study include a lack of randomization and follow-up rate to assess for recurrence. The low compliance rate may be due to procedure cancelations/difficulty scheduling because of changing coronavirus disease 2019 guidelines.

CONCLUSIONS

Compared to literature-reported statistics for its laparoscopic counterpart, combined endoscopic robotic surgery was associated with decreased operation times and resection site polyp recurrence. See Video Abstract at http://links.lww.com/DCR/C208 .

CIRUGA ROBTICA ENDOSCPICA COMBINADA PARA PLIPOS DE COLON COMPLEJOS

ANTECEDENTES:La cirugía robótica endoscópica combinada es una técnica quirúrgica que modifica la cirugía laparoscópica endoscópica tradicional con asistencia robótica para ayudar en la extracción de pólipos colónicos complejos. Esta técnica está previamente descrita en la literatura, pero carece de datos de seguimiento de los pacientes.OBJETIVO:Evaluar la seguridad y los resultados de la cirugía robótica endoscópica combinada.DISEÑO:Revisión retrospectiva de una base de datos prospectiva.AJUSTE:Hospital General East Jefferson, Metairie LouisianaPACIENTES:Noventa y tres pacientes consecutivos y sometidos a cirugía robótica endoscópica combinada por un solo cirujano colorrectal desde marzo de 2018 hasta octubre de 2021.PRINCIPALES MEDIDAS DE RESULTADO:Tiempo operatorio, complicación intraoperatoria, complicación posoperatoria a los 30 días, duración de la estancia hospitalaria y resultados del informe patológico de seguimiento.RESULTADOS:La cirugía robótica endoscópica combinada se completó en 88 de 93 (95%). Entre los 88 participantes que completaron la cirugía robótica endoscópica combinada, la edad promedio fue de 66 años (desviación estándar = 10), índice de masa corporal de 28,8 (desviación estándar = 6) y el historial de cirugías abdominales previas de 1 (desviación estándar = 1). La mediana del tiempo operatorio y el tamaño de los pólipos fueron 72 minutos (rango 31-184 minutos) y 40 milímetros (rango 5-180 milímetros), respectivamente. Las ubicaciones de pólipos más comunes fueron el ciego, colon ascendente y transverso (31%, 28%, 25%). La patología demostró principalmente adenoma tubular (76%). Los datos de 40 pacientes sometidos a una colonoscopia de seguimiento estaban disponibles. El tiempo medio de seguimiento fue de 7 meses (rango 3-22 meses). Un paciente (2,5%) presentó recurrencia polipoidea en el sitio de resección.LIMITACIONES:Las limitaciones de nuestro estudio incluyeron la falta de aleatorización y la tasa de seguimiento para evaluar la recurrencia. La baja tasa de seguimiento puede deberse a la renuencia del paciente en hacerse una colonoscopia o cancelaciones de procedimientos por la dificultad para programar debido a cambios de COVID-19.CONCLUSIÓN:En comparación con las estadísticas reportadas en la literatura para su contraparte laparoscópica, la cirugía robótica endoscópica combinada se asoció con reducción en tiempos de operación y recurrencia de pólipos en el sitio de resección. Consulte Video Resumen en http://links.lww.com/DCR/C208 . (Traducción - Dr. Fidel Ruiz Healy ).

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.

Comparison of efficiency and safety between dual-clip and rubber band-assisted ESD and conventional ESD for colonic lateral spreading tumors (LSTs) with different levels of technical difficulty: a retrospective case–control study

Background

Dual-clip and rubber band-assisted endoscopic submucosal dissection (DCRB-ESD) is a useful technique in the management of lateral spreading tumors (LSTs) of the colon and is suggested by researchers compared with conventional ESD (C-ESD). The aim of this retrospective study is to further analyze the efficiency and safety of DCRB-ESD in a setting with varying technical difficulties.

Methods

Patients who underwent endoscopic treatment (DCRB-ESD or C-ESD) due to LSTs between Jan 1st, 2019 and Jan 1st, 2022, were retrospectively collected. Patients were classified into the following two groups: the DCRB-ESD group (n = 46) and the C-ESD group (n = 81). Baselines were compared and propensity score matching (PSM) was employed to manage the heterogeneity. The technical difficulty and outcomes of the two groups were evaluated based on a semiquantitative model (CS-CRESD) previously described.

Results

The baseline characteristics of the two groups were balanced except sex and LST classification before PSM and were corrected after PSM. The median ESD operation time of DCRB-ESD was shorter than that of C-ESD (32 vs 41 and 30 vs 44 before and after PSM respectively, P < 0.05). The operation durations of cases with different CS-CRESD scores were different (P < 0.05). In the subgroup with a score of 0, DCRB-ESD showed no advantage than C-ESD in terms of operation duration before and after PSM. In subgroups with a score of 1–3, DCRB-ESD was faster than C-ESD. In subgroups with a score of 4–5, the between-group operation duration was not significantly different due to the limited number of cases, although the median time of DCRB-ESD was shorter. The R0 resection rates, curative resection, complications, and additional surgery in both groups were not significantly different. No adverse events, such as a clip falling off or rubber band rupturing occurred during this study.

Conclusion

DCRB-ESD was an efficient and safe procedure in the management of colonic LSTs. With DCRB-ESD, the operation duration of difficult cases can be shortened without sacrificing complication risk. However, not all cases would benefit from DCRB-ESD. For easy cases (CS-CRESD score = 0), DCRB-ESD may not be prior to C-ESD by experienced endoscopists. A pre-ESD technical difficulty evaluation was recommended to decide whether to perform DCRB-ESD or not.

Predictors for malignant potential and deep submucosal invasion in colorectal laterally spreading tumors

BACKGROUND

Colorectal laterally spreading tumors (LSTs) with malignant potential require en bloc resection by endoscopic submucosal dissection (ESD), but lesions with deep submucosal invasion (SMI) are endoscopically unresectable.

AIM

To investigate the factors associated with high-grade dysplasia (HGD)/carcinoma and deep SMI in colorectal LSTs.

METHODS

The endoscopic and histological results of consecutive patients who underwent ESD for colorectal LSTs in our hospital from June 2013 to March 2019 were retrospectively analyzed. The characteristics of LST subtypes were compared. Risk factors for HGD/carcinoma and deep SMI (invasion depth ≥ 1000 μm) were determined using multivariate logistic regression.

RESULTS

A total of 323 patients with 341 colorectal LSTs were enrolled. Among the four subtypes, non-granular pseudodepressed (NG-PD) LSTs (85.5%) had the highest rate of HGD/carcinoma, followed by the granular nodular mixed (G-NM) (77.0%), granular homogenous (29.5%), and non-granular flat elevated (24.2%) subtypes. Deep SMI occurred commonly in NG-PD LSTs (12.9%). In the adjusted multivariate analysis, NG-PD [odds ratio (OR) = 16.8, P < 0.001) and G-NM (OR = 7.8, P < 0.001) subtypes, size ≥ 2 cm (OR = 2.2, P = 0.005), and positive non-lifting sign (OR = 3.3, P = 0.024) were independently associated with HGD/carcinoma. The NG-PD subtype (OR = 13.3, P < 0.001) and rectosigmoid location (OR = 8.7, P = 0.007) were independent risk factors for deep SMI.

CONCLUSION

Because of their increased risk for malignancy, it is highly recommended that NG-PD and G-NM LSTs are removed en bloc through ESD. Given their substantial risk for deep SMI, surgery needs to be considered for NG-PD LSTs located in the rectosigmoid, especially those with positive non-lifting signs.

Efficacy and Safety of Four Different Endoscopic Treatments for Early Esophageal Cancer: a Network Meta-analysis

PURPOSE

Cap-assisted endoscopic mucosal resection (EMRC), ligation-assisted endoscopic mucosal resection (EMRL), endoscopic submucosal dissection (ESD), and multiband mucosectomy (MBM) are used for treating early esophageal cancer patients. Our aim was to compare the efficacy and safety of four different endoscopic treatments.

METHODS

Electronic databases (PubMed, Cochrane, Embase, and Web of Science) were systematically searched to include relevant studies published from database inception until February 15, 2021. There were no date or language restrictions. Data related to study such as characteristics, methods, outcomes, and risks of bias were extracted by two reviewers.

RESULTS

A total of 11 articles with 1880 patients were included. The results of the network meta-analysis showed that ESD was a better choice considering the efficacy of en bloc resection rate (surface under the cumulative ranking curves (SUCRA) = ESD: 99.5%, EMRC: 26.5%, MBM: 24.1%) and local recurrence rate (SUCRA = EMRC: 95.6%, MBM: 42.9%, ESD: 11.6%). MBM had a lower rate of side effects compared to the other treatments: perforation rate (SUCRA = ESD: 100%, EMRC: 48.1%, MBM: 1.9%), stricture rate (SUCRA = ESD: 99.8%, MBM: 40.8%, EMRC: 9.4%), and bleeding rate (SUCRA = EMRC: 69.4%, ESD: 62.2%, EMRL: 61.6%, MBM: 6.8%). MBM also had the shortest operation time and smallest diameter of the specimens.

CONCLUSION

The MBM endoscopic treatment was recommended for early esophageal cancer patients, but considering the increase in lesion size, ESD would be better.

A Comparison of Incomplete Resection Rate of Large and Small Colorectal Polyps by Cold Snare Polypectomy

BACKGROUND & AIMS

There are limited data regarding the safety and efficacy of cold snare polypectomy (CSP) for large colorectal polyps. We evaluated factors affecting the clinical outcomes of CSP for polyps between 5 and 15 mm in size.

METHODS

This was a prospective single-center observational study involving 1000 patients undergoing colonoscopy. Polyps (5-15 mm) were removed using CSP, and biopsies were taken from the resection margin. The primary outcome was the incomplete resection rate (IRR), and was determined by the presence of residual neoplasia on biopsy. Correlations between IRR and polyp size, morphology, histology, and resection time were assessed by generalized estimating equation model.

RESULTS

A total of 440 neoplastic polyps were removed from 261 patients. The overall IRR was 2.27%, 1.98% for small (5-9 mm) vs 3.45% for large (10-15 mm) polyps (P = .411). In univariate analysis, the IRR was more likely to be related to sessile serrated lesions (odds ratio [OR], 6.93; 95% confidence interval [CI], 1.88-25.45; P = .004), piecemeal resection (OR, 11.83; 95% CI, 1.20-116.49; P = .034), and prolonged resection time >60 seconds (OR, 7.56; 95% CI, 1.75-32.69; P = .007). In multivariable regression analysis, sessile serrated lesions (OR, 6.45; 95% CI, 1.48-28.03; P = .013) and resection time (OR, 7.39; 95% CI, 1.48-36.96; P = .015, respectively) were independent risk factors for IRR. Immediate bleeding was more frequent with resection of large polyps (6.90% vs 1.42%; P = .003). No recurrence was seen on follow-up colonoscopy in 37 cases with large polyps.

CONCLUSIONS

CSP is safe and effective for removal of colorectal polyps up to 15 mm in size, with a low IRR. (ClinicalTrials.gov; Number: NCT03647176).

Management of Significant Polyp and Early Colorectal Cancer Is Optimized by Implementation of a Dedicated Multidisciplinary Team Meeting: Lessons Learned From the United Kingdom National Program

BACKGROUND

The concept of significant polyps and early colorectal cancer encompasses complex polyps not amenable to routine snare polypectomy or where malignancy cannot be excluded. The assessment and management of these lesions is contentious and increasingly important due to the significant risk of over- or undertreatment.

OBJECTIVE

Following the recommendations of the Significant Polyps and Early Colorectal Cancer National Program, we implemented a dedicated multidisciplinary team meeting and analyzed the influence on patient outcomes.

DESIGN

This was a retrospective study using a prospectively collected database of patients discussed at the dedicated multidisciplinary team meeting.

SETTINGS

This study was conducted in a single tertiary-care center.

PATIENTS

Consecutive patients with significant polyps and early colorectal cancer were identified either through the Bowel Cancer Screening Program or colonoscopy for symptomatic patients.

MAIN OUTCOME MEASURES

Proportions of patients who had organ preservation, and secondary treatment and recurrence rate served as outcome measures.

RESULTS

Overall, 135 patients discussed at the dedicated multidisciplinary team meeting were included, with a median age of 71 years. Median size of the lesions was 25 mm, and 39% were in the rectum. Patients were discussed either after the lesion was removed during the initial colonoscopy (n = 38), of whom 16 (42%) had unexpected cancer, or had no initial treatment with subsequent case review (n = 97). Of these 97 patients, 46 underwent endoscopic excision (26% cancer), 20 trans-anal excision (10% cancer), 23 primary surgical resection (35% cancer), and 8 had no treatment. In 104 (82%) patients, organ preservation was achieved. Secondary surgery was required in 7 of 104 (6.7%) patients after local excision due to radical treatment of high-risk T1 lesions, local recurrence, or patients' decisions. The cumulative hazard estimates for recurrence after a median follow-up of 18.5 months was less than 10% for both benign and malignant lesions.

LIMITATIONS

This study was limited by its relatively small sample size and single-center setting.

CONCLUSIONS

A dedicated multidisciplinary team meeting improved the management of significant polyps and early colorectal cancer, safely refining organ preservation for patients, with low recurrence rates. See Video Abstract at http://links.lww.com/DCR/B826.

MANEJO DE SPECC PLIPO COMPLEJO Y CNCER COLORRECTAL TEMPRANO ES OPTIMIZADO MEDIANTE LA IMPLEMENTACIN DE REUNIONES DE UN EQUIPO MULTIDISCIPLINARIO ESPECIALIZADOS LECCIONES APRENDIDAS DEL PROGRAMA NACIONAL DEL REINO UNIDO

ANTECEDENTES:El concepto de pólipos complejos y cáncer colorrectal temprano abarca engloba pólipos avanzados que no es posible la reseccion endoscopica rutinaria, o aquellos en los que no se puede excluir malignidad. La evaluación y el manejo de estas lesiones es controversial y cada vez más importante debido al riesgo significativo de ser tratadas o no.OBJETIVO:Siguiendo las recomendaciones del Programa Nacional de Pólipos Complejos y Cáncer Colorrectal Temprano, implementamos reuniónes del equipo multidisciplinario especializado y analizamos el impacto en los resultados de los pacientes.DISEÑO:Estudio retrospectivo sobre una base de datos recopilada prospectivamente de los pacientes discutidos en la reunión del equipo multidisciplinario especializado.AJUSTE:Este estudio se realizó en un centro de atención terciaria.PACIENTES:Pacientes consecutivos con pólipos complejos y cáncer colorrectal temprano identificado a través del Programa de detección de cáncer intestinal o colonoscopia para pacientes sintomáticos.PRINCIPALES MEDIDAS DE RESULTADO:Proporción de pacientes que tuvieron preservación de órganos, tratamiento secundario y tasa de recurrencia.RESULTADOS:En total, se incluyeron 135 pacientes discutidos en la reunión del equipo multidisciplinario especializado dedicada, con una media de edad de 71 años. El tamaño medio de las lesiones fue de 25 mm y el 39% estaban en el recto. Se discutio de los pacientes después de que se resecara la lesión durante la colonoscopia inicial [n = 38, de los cuales 16 (42%) tenían un cáncer imprevisto] o no recibieron tratamiento de inicio, con revisión posterior del caso (n = 97). De estos, 46/97 fueron sometidos a resección endoscópica (26% cáncer), 20/97 resección transanal (10% cáncer), 23/97 resección quirúrgica primaria (35% cáncer) y 8/97 no recibieron tratamiento. En 104 (82%) pacientes, se logró la preservación de órgano. Cirugía secundaria fue requeria en 7/104 (6,7%) pacientes después de la resección local debido a tratamiento radical de lesiones T1 de alto riesgo, recidiva local o decisión del paciente. Las estimaciones de riesgo acumulativo de recurrencia después de una media de seguimiento de 18,5 meses fue inferior al 10% tanto para las lesiones benignas como para las malignas.LIMITACIONES:Tamaño de muestra relativamente pequeño y entorno de un solo centro.CONCLUSIONES:La Reunion del equipo multidisciplinario especializado mejoró el manejo de los pólipos complejos y cáncer colorrectal temprano, refinando de manera segura la preservación de órganos para los pacientes, con bajas tasas de recurrencia. Consulte Video Resumen en http://links.lww.com/DCR/B826. (Traducción- Dr. Francisco M. Abarca-Rendon).

Risk Factors for Fever After Esophageal Endoscopic Submucosal Dissection and Its Derived Technique

Background

Fever is one of the postoperative adverse events of endoscopic submucosal dissection and its derived technique, but the probability and risk factors of postoperative fever are still unclear. The aim of the current study was to investigate the incidence and risk factors of postoperative fever after esophageal lesion removal.

Methods

We conducted a retrospective study of 446 patients who underwent esophageal endoscopic submucosal dissection and its derived technique between January 2014 and January 2020. Cases included in this study were divided into fever and non-fever groups.

Results

Postoperative fever developed in 135 patients (30.3%). The median (range) highest fever temperature was 38 (37.8–38.4)°C, the median (range) duration of fever was 1 (1–2) day, and 127 (94.1%) patients developed fever within 24 h after operation. Through logistic regression analysis, factors associated with postoperative fever were age (OR: 1.740, 95% CI: 1.005–3.013, p = 0.048), lesion size (OR: 2.007, 95% CI: 1.198–3.362, p = 0.008), operation time (OR: 3.007, 95% CI: 1.756–5.147, p < 0.001) and nasogastric tube placement (OR: 1.881, 95% CI: 1.165–3.037, p = 0.010), while prophylactic antibiotics (OR: 0.181, 95% CI: 0.082–0.401, p < 0.001) were negatively associated with fever.

Conclusions

Age ≥52 years old, lesion size ≥19 mm, operation time ≥37 min, and nasogastric tube placement are risk factors for postoperative fever after esophageal endoscopic submucosal dissection and its derived technique, prophylactic antibiotic use after operation may help reduce fever rate. Attention should be paid to such patients to minimize the risk of postoperative fever.

Comparison of precutting endoscopic mucosal resection and endoscopic submucosal dissection for large (20-30 mm) flat colorectal lesions

BACKGROUND AND AIM

The complete and safe removal of large (≥ 20 mm) colorectal lesions is an area of concern. Endoscopic submucosal dissection (ESD) effectively removes these lesions compared with endoscopic mucosal resection (EMR). However, ESD requires advanced techniques, longer procedure time, and high cost. Precutting EMR (EMR-P) is a modified EMR method that overcomes the limitations of EMR. This study aimed to compare the efficacy and safety of EMR-P and ESD in large (20-30 mm) flat colorectal lesions.

METHODS

This was a retrospective analysis of cases in which 20- to 30-mm flat colorectal lesions were resected at Seoul St. Mary's Hospital from January 2014 to December 2019. Propensity score matching was performed to control for possible confounders.

RESULTS

Two hundred and ninety-nine patients were included in this study. After matching, 90 patients were assigned to each group. There were no significant difference in complete resection rates (92.2% vs 92.2%, P = 1.000), en bloc resection rates (95.6% vs 97.8%, P = 0.682), and mean size of lesions (22.9 ± 3.1 mm vs 23.0 ± 3.1 mm, P = 0.867) between EMR-P and ESD. Procedure time was significantly shorter with EMR-P (11.0 ± 6.5 min vs 37.0 ± 19.3 min, P < 0.001). The adverse events rate was not significantly different between both groups. No local recurrence occurred in both groups.

CONCLUSIONS

Precutting EMR was not significantly different to ESD in terms of complete resection rate and en bloc resection rate for 20- to 30-mm flat colorectal lesions without fibrosis. Furthermore, EMR-P has shorter procedure time than ESD. EMR-P could be considered one of standard treatments for large flat colorectal lesions.

Easily-injectable shear-thinning hydrogel provides long-lasting submucosal barrier for gastrointestinal endoscopic surgery

Submucosal injection material has shown protective effect against gastrointestinal injury during endoscopic surgery in clinic. However, the protective ability of existing submucosal injection material is strictly limited by their difficult injectability and short barrier time. Herein, we report a shear-thinning gellan gum hydrogel that simultaneously has easy injectability and long-lasting barrier function, together with good hemostatic property and biocompatibility. Shear-thinning property endows our gellan gum hydrogel with excellent endoscopic injection performance, and the injection pressure of our gellan gum hydrogel is much lower than that of the small molecule solution (50 wt% dextrose) when injected through the endoscopic needle. More importantly, our gellan gum hydrogel shows much stronger barrier retention ability than normal saline and sodium hyaluronate solution in the ex vivo and in vivo models. Furthermore, our epinephrine-containing gellan gum hydrogel has a satisfactory hemostatic effect in the mucosal lesion resection model of pig. These results indicate an appealing application prospect for gellan gum hydrogel utilizing as a submucosal injection material in endoscopic surgery.

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Submucosal injection materials are widely used in endoscopic surgery to protect against gastrointestinal injury.

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Gellan gum hydrogel with shear-thinning character is a novel submucosal injection material.

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Gellan gum hydrogel simultaneously has easy injectability and long-lasting barrier performance in vivo.

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Epinephrine-containing gellan gum hydrogel has a satisfactory hemostatic effect.

Hybrid endoscopic mucosal resection and full-thickness resection for large colonic polyps harboring a small focus of invasive cancer: a case series

Endoscopic treatment of large laterally spreading tumors (LSTs) with a focus of submucosally invasive colorectal cancer (T1 CRC) can be challenging. We evaluated outcomes of a hybrid resection technique using piecemeal endoscopic mucosal resection (pEMR) and endoscopic full-thickness resection (eFTR) in patients with large colonic LSTs containing suspected T1 CRC. Six hybrid pEMR-eFTR procedures for T1 CRCs were registered in a nationwide eFTR registry between July 2015 and December 2019. In all cases, the invasive part of the lesion was successfully isolated with eFTR; with eFTR, histologically complete resection of the invasive part was achieved in 5 /6 patients (83.3 %). No adverse events occurred during or after the procedure. The median follow-up time was 10 months (range 6-27), with all patients having undergone ≥ 1 surveillance colonoscopy. One patient had a small adenomatous recurrence, which was removed endoscopically. In conclusion, hybrid pEMR-eFTR is a promising noninvasive treatment modality that seems feasible for a selected group of patients with large LSTs containing a small focus of T1 CRC.

Prediction of technically difficult endoscopic submucosal dissection for large superficial colorectal tumors: a novel clinical score model

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is a promising technique for removing superficial GI tumors, but ESD is technically difficult. The aim of this study was to establish a clinical score model for grading technically difficult colorectal ESD.

METHODS

Data on patients, lesions, and outcomes of colorectal ESD at 2 centers were analyzed. The objective parameter of successful ESD within 60 minutes was set as an endpoint to evaluate the difficulty. Independent predictors of difficulty in the derivation cohort were identified by multiple logistic regression analysis and used to develop a clinical score. We validated the score model in the validation cohort.

RESULTS

The clinical score comprised tumor size of 30 to 50 mm (1 point) or ≥50 mm (2 points), at least two-thirds circumference of the lesion (2 points), location in the cecum (1 point), flexure (2 points) or dentate line (1 point), and laterally spreading tumor nongranular lesions (1 point). Areas under the receiver operator characteristic curves for the score model were comparable (derivation [.70] vs internal validation [.69] vs external validation [.69]). The probability of successful ESD within 60 minutes in easy (score = 0), intermediate (score = 1), difficult (score = 2-3), and very difficult (score ≥4) categories were 75.0%, 51.3%, 35.6%, and 3.4% in the derivation cohort; 73.3%, 47.9%, 31.8%, and 16.7% in the internal validation cohort; and 79.5%, 66.7%, 43.3%, and 20.0% in the external validation cohort, respectively.

CONCLUSIONS

This clinical score model accurately predicts the probability of successful ESD within 60 minutes and can be applied to grade the technical difficulty before the procedure.

BRD7 Promotes Cell Proliferation and Tumor Growth Through Stabilization of c-Myc in Colorectal Cancer

BRD7 functions as a crucial tumor suppressor in numerous malignancies. However, the effects of BRD7 on colorectal cancer (CRC) progression are still unknown. Here, based on the BRD7 knockout (BRD7^-/-) and BRD7 ^flox/flox (BRD7^+/+) mouse models constructed in our previous work, we established an azoxymethane/dextran sodium sulfate (AOM/DSS)-induced mouse model. BRD7^+/+ mice were found to be highly susceptible to AOM/DSS-induced colitis-associated CRC, and BRD7 significantly promoted cell proliferation and cell cycle G1/S transition but showed no significant effect on cell apoptosis. Furthermore, BRD7 interacted with c-Myc and stabilized c-Myc by inhibiting its ubiquitin-proteasome-dependent degradation. Moreover, restoring the expression of c-Myc in BRD7-silenced CRC cells restored cell proliferation, cell cycle progression, and tumor growth in vitro and in vivo. In addition, BRD7 and c-Myc were both significantly upregulated in CRC patients, and high expression of these proteins was associated with clinical stage and poor prognosis in CRC patients. Collectively, BRD7 functions as an oncogene and promotes CRC progression by regulating the ubiquitin-proteasome-dependent stabilization of c-Myc protein. Targeting the BRD7/c-Myc axis could be a potential therapeutic strategy for CRC.

Multiparametric MRI-based machine learning models for preoperatively predicting rectal adenoma with canceration

OBJECTIVES

To propose multiparametric MRI-based machine learning models and assess their ability to preoperatively predict rectal adenoma with canceration.

MATERIALS AND METHODS

A total of 53 patients with postoperative pathology confirming rectal adenoma (n = 29) and adenoma with canceration (n = 24) were enrolled in this retrospective study. All patients were divided into a training cohort (n = 42) and a test cohort (n = 11). All patients underwent preoperative pelvic MR examination, including high-resolution T2-weighted imaging (HR-T2WI) and diffusion-weighted imaging (DWI). A total of 1396 radiomics features were extracted from the HR-T2WI and DWI sequences, respectively. The least absolute shrinkage and selection operator (LASSO) was utilized for feature selection from the radiomics feature sets from the HR-T2WI and DWI sequences and from the combined feature set with 2792 radiomics features incorporating two sequences. Five-fold cross-validation and two machine learning algorithms (logistic regression, LR; support vector machine, SVM) were utilized for model construction in the training cohort. The diagnostic performance of the models was evaluated by sensitivity, specificity and area under the curve (AUC) and compared with the Delong's test.

RESULTS

Ten, 8, and 25 optimal features were selected from 1396 HR-T2WI, 1396 DWI and 2792 combined features, respectively. Three group models were constructed using the selected features from HR-T2WI (Model_T2), DWI (Model_DWI) and the two sequences combined (Model_combined). Model_combined showed better prediction performance than Model_T2 and Model_DWI. In Model_combined, there was no significant difference between the LR and SVM algorithms (p = 0.4795), with AUCs in the test cohort of 0.867 and 0.900, respectively.

CONCLUSIONS

Multiparametric MRI-based machine learning models have the potential to predict rectal adenoma with canceration. Compared with Model_T2 and Model_DWI, Model_combined showed the best performance. Moreover, both LR and SVM have equal excellent performance for model construction.

The Most Influential Publications on Endoscopic Submucosal Dissection: A Bibliometric Analysis

Background/Aims: Endoscopic submucosal dissection (ESD) is the first-line treatment for superficial gastrointestinal neoplasms with negligible lymph node metastasis. It has evolved through improvements in expertise and equipment, increased understanding of indications and short- and long-term outcomes, and better management of complications. This study aimed to assess and characterize the most influential publications in ESD research.Materials and Methods: We searched the top 50 most cited articles using Web of Science Core Collection (WoSCC) and Google Scholar (GS) from the inception of these services to January 2019. The top 50 Altmetric Attention Score (AAS) articles based on online media mentions were also searched. Each article was evaluated for the number of citations, title, journal, and publication year.Results: The number of citations for the top 50 WoSCC articles on ESD ranged from 37 to 199; Endoscopy published the most articles (20%). Among the top 50 GS articles, Gastrointestinal Endoscopy published the most ESD articles (34%) and the most shared AAS articles (42.6%). PubMed Central article citations in WoSCC or GS showed significant correlation with those from each metric, unlike AAS. The words with the highest relevance scores were “submucosal tunnel dissection,” “guideline,” “novel submucosal gel,” “adhesive material,” “cell sheet,” “esophageal ulcer,” “hemospray,” and “endoscopic closure,” while the following words were influential: “meta-analysis,” “esophageal stricture,” “perforation,” “bleeding,” “fibrin glue,” “artificial ulcer,” “porcine model” and “esophageal squamous cell neoplasia,” excluding “ESD.”Conclusions: This study presents a detailed list of influential articles, journals, and topic words.

Effectiveness of underwater endoscopic mucosal resection versus conventional endoscopic mucosal resection for 10 to 20 mm colorectal polyps: A protocol of systematic review and meta-analysis

BACKGROUND

Endoscopic mucosal resection (EMR) is a standard method commonly for removing 10 to 20 mm colorectal polyps. While the incidence of residual or recurrent after conventional EMR is remarkably high. Underwater endoscopic mucosal resection (UEMR) as an alternative technique to conventional EMR for removing colorectal polyps has high adenoma detection and complete resection rates, improves patient comfort, decreases sedation needs, eliminates the risks associated with submucosal injection, and reduces snare and diathermy-induced mucosal injury. We will conduct a comprehensive systematic review and meta-analysis to compare the effectiveness of these two therapies in the management of 10 to 20 mm colorectal polyps.

METHODS

PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, China Science and Technology Journal Database and Chinese Biomedical Literature Database will be searched from inception of databases to November 2020 without language limitation. Two reviewers will independently conduct article selection, data collection, and assessment of risk of bias. Any disagreement will be resolved by discussion with the third reviewer. Review Manager Software 5.3 will be used for meta-analysis. The Cochrane risk of bias tool will be used to assess the risk of bias.

RESULTS

This study will provide a systematic synthesis of current published data to compare the effectiveness of UEMR and conventional EMR for 10 to 20 mm colorectal polyps.

CONCLUSIONS

This systematic review and meta-analysis will provide clinical evidence as to whether UEMR is more effective and safer than conventional EMR for 10 to 20 mm colorectal polyps.

STUDY REGISTRATION NUMBER

INPLASY2020100006.

Evaluation of recurrence and surgical complementation rates after endoscopic resection of large colorectal non-pedunculated lesions

BACKGROUND AND AIM

the process that leads to the development of colorectal cancer takes many years and most tumors originate from polyps and non-polypoid lesions. Techniques of endoscopic resection are surgical treatment options, even in case of large lesions or with initial invasion. This study aimed to evaluate the recurrence and surgical complementation rates after endoscopic resection of large colorectal non-pedunculated lesions.

METHODS

a retrospective, longitudinal and descriptive trial was performed via an analysis of colonoscopies with the resection of non-pedunculated lesions larger than 3 cm, performed between 2014 and 2017.

RESULTS

sixty-two lesions were included from 61 patients and 32 (52.5 %) were female. The age ranged from 36 to 89 years, with a mean age of 60.5 years. Lesions had an average diameter of 40.08 mm, ranging from 30 to 80 mm. Regarding the location of the lesions, the most frequent colonic segments were the ascending and rectum, both accounting for 22.6 %. Considering the morphologic endoscopic classification, 67.7 % were granular laterally spreading tumors (LST), 38.8 % were homogeneous granular and 29 % were mixed granular. The most frequent histological types were tubulovillous adenoma (30.7 %) and intramucosal adenocarcinoma (29 %). The resection technique was piecemeal mucosectomy in 85.5 %. Five lesions were removed by en bloc mucosectomy, two (3.2 %) by endoscopic submucosal dissection (ESD) and two (3.2 %) by a hybrid technique. The recurrence rate was 25.8 %. Three patients needed complementary surgical treatment and the clinical success of endoscopic treatment was 95.1 %.

CONCLUSION

recurrence rate after endoscopic resection of large colorectal lesions was 25.8 % and surgical complementation rate due to failure in the endoscopic treatment of recurrence was 4.8 %.

Valuing innovative endoscopic techniques: prophylactic clip closure after endoscopic resection of large colon polyps

BACKGROUND AND AIMS

Clip closure of the mucosal defect after resecting large (≥20 mm) nonpedunculated colorectal polyps reduces postprocedure bleeding and is cost saving for payers. Clip costs are not reimbursed by payers, posing a major barrier to adoption of this technique in the community. We aimed to determine appropriate clip costs to support broader use of this procedure in practice.

METHODS

We performed budget impact analysis using our recent decision analytic model, comparing prophylactic clip closure with no clip closure on national cost and outcomes data, to determine the maximum feasible clip price while maintaining cost savings in practice. Sensitivity analyses were performed on important clinical factors.

RESULTS

In the original model, the baseline postprocedure bleeding risk was 6.8%, increasing cost of care by $614.11 averaged among all patients undergoing large polyp resection without clip closure. Prophylactic clip closure of only large right-sided polyps reduced postprocedure bleeding risk by 70.7% but resulted in cost saving only if the price of clips was $100 or less. Comparatively, prophylactic clip closure of large left-sided polyps had no clinical benefit and was not cost saving. Clip closure strategies focused only on extra-large polyps (≥40 mm), or patients taking antithrombotics regardless of polyp characteristics, were only minimally cost saving. Cost savings and maximum tolerated clip prices depended on medical comorbidity, which directly influences the costs of care to manage postprocedure bleeding.

CONCLUSIONS

Prophylactic clip closure after endoscopic resection of large colon polyps, particularly those in the right colon segment, is cost saving but requires clip costs less than $100. Translating these findings into practice requires gastroenterology practices to obtain reimbursement from payers for improved clinical outcomes and to align commercial clip prices with this clinical indication.

Intra-abdominal pressure during endoscopic full-thickness resection comparing manual and automatic control insufflation: a block-randomized porcine study

BACKGROUND AND STUDY AIMS

An automatic carbon dioxide (CO2) insufflating system (SPACE) was developed to stabilize intra-lumenal pressure (ILP) during endoscopic interventions. This study investigated whether SPACE could improve the control and monitoring of extra-lumenal intra-abdominal pressure (IAP) after establishing a perforation during endoscopic full-thickness resection (EFTR) of the gastric wall in porcine models.

MATERIALS AND METHODS

After first establishing the optimal preset pressure for gastric EFTR in four pigs, we compared IAP dynamics during EFTR between manual insufflation and SPACE using a block-randomized study (n = 10). IAP was percutaneously monitored and plotted on a timeline graph every 5 s. The maximal IAP and the area under the IAP curve exceeding 10 mmHg (AUC≥10 mmHg) were compared between groups, with the agreement between IAP and endolumenally monitored ILP also analyzed for animals in the SPACE group.

RESULTS

In the first study, 8 mmHg was identified as the most preferable preset pressure after establishment of the perforation. In the randomized study, the mean maximal IAP in the SPACE group was significantly lower than that in the manual insufflation group (11.0 ± 2.0 mmHg vs. 17.0 ± 3.5 mmHg; P = 0.03). The mean AUC≥10 mmHg was also significantly smaller in the SPACE group. Bland-Altman analysis demonstrated agreement between IAP and ILP within a range of ± 1.0 mmHg.

CONCLUSIONS

SPACE could be used to control and safely monitor IAP during gastric EFTR by measuring ILP during perforation of the gastric wall.

Risk factors associated with clinical outcomes of endoscopic mucosal resection for colorectal laterally spreading tumors: A Honam Association for the Study of Intestinal Diseases (HASID) multicenter study

BACKGROUND/AIMS

Colorectal laterally spreading tumors (LSTs) are large and superficial neoplasms. Most are adenomatous lesions. Endoscopic mucosal resection (EMR) is a standard technique of removing precursor colorectal lesions. The aim of the present study was to assess the factors associated with the clinical outcomes of EMR for LSTs.

MATERIALS AND METHODS

A total of 275 patients with LSTs who underwent EMR were enrolled in the study. The clinical outcomes of the patients were analyzed by retrospectively reviewing their medical records.

RESULTS

The en bloc resection and R0 resection rates were 86.9% and 80.4%, respectively. The bleeding and perforation rates were 7.6% and 0.4%, respectively. The frequency of high-grade dysplasia and adenocarcinoma histology was significantly higher, and the procedure time was significantly longer in LSTs >20 mm than in those ≤20 mm. The R0 resection rate was significantly higher in LSTs ≤20 mm than in those >20 mm. The frequency of piecemeal resection was significantly higher in LSTs with an adenomatous and cancerous pit pattern than in those with a non-neoplastic pit pattern. The frequency of piecemeal resection was significantly higher in LSTs with adenocarcinoma than in those with low-grade dysplasia. Multivariate analysis revealed that adenomatous pit pattern, high-grade dysplasia, or adenocarcinoma was a significant independent risk factor of LSTs for piecemeal resection after EMR.

CONCLUSION

EMR is useful for treating ≤20 mm LSTs with regard to curative resection and procedure time. LSTs with an adenomatous pit pattern, high-grade dysplasia, or adenocarcinoma are significant independent risk factors for piecemeal resection after EMR.

Importance of Resection Margins in the Treatment of Rectal Adenomas by Transanal Endoscopic Surgery

BACKGROUND

Polypectomy is the gold standard for treating colorectal adenomas up to 2 cm in size. For larger lesions, various procedures ranging from endoscopy to transanal surgery can be performed and achieve varying results for en bloc resection and recurrence. There are no clear guidelines for dealing with involved resection margins. We assess the recurrence of rectal adenomas operated using TEM with full-thickness wall excision with or without free resection margins and define optimal endoscopic follow-up.

METHOD

Observational study with prospective data collection, including patients undergoing TEM between 6/2004 and 11/2017, with definitive diagnosis of rectal adenoma. Data on epidemiological, preoperative, surgical, postoperative, pathological, and follow-up variables were recorded. Univariate analysis, follow-up risk function, and multivariate logistic regression analysis were performed to detect risk factors for recurrence.

RESULTS

TEM was indicated in 736 patients; 481 adenomas were identified in the preoperative biopsy, of which 95 were infiltrating adenocarcinomas (19.8%) in the definitive pathology study. With a minimum follow-up of 1 year, 372 patients were included. Pathology study showed free margins in 324 (87%). Recurrences were recorded in 15 patients (4%), up to 18 months in the free margins group and up to 24 months in the involved margins group. Thirteen patients with recurrence (86.6%) were treated with TEM. No predictors of recurrence were found in the multivariate analysis.

CONCLUSION

TEM is the technique of choice for treating rectal adenomas and recurrences, achieving a low relapse rate. Follow-up must be adapted to resection margins and should be extended to 24 months.

Gastric lipomas: a case series and review of a rare tumor

The purpose of the study was to investigate and review the multimodality imaging findings of gastric lipomas. Seven patients with gastric lipomas identified by CT imaging at a single institution between 2003 and 2017 were retrospectively evaluated. Patient demographics, clinical presentation, non-invasive imaging, endoscopic, and pathological findings were recorded.The most common location for gastric lipoma was the gastric antrum (3/7). The mean lipoma size was 2.7 cm ± 0.8 cm. Six out of seven lipomas demonstrated homogenous fat attenuation with mean Hounsfield units (HU) between −80 and −120. A single lipoma measuring −50 HU demonstrated soft tissue septations. In addition to routine CT and MRI, gastric lipomas were diagnosed on the low-dose CT protocols such as coronary calcium scoring, renal stone, and positron emission tomography-CT (PET-CT). Our CT findings corroborate those reported previously. Soft tissue septations visualized in one lesion likely represented post-biopsy changes, adding this etiology to a differential which previously included only ulceration. Cases characterized by MRI are rare in the literature, and our study provides one such example. To our knowledge this study represents the first documentation of gastric lipomas on PET-CT and other low-dose CT imaging protocols.

Variations in the management of significant polyps and early colorectal cancer: results from a multicentre observational study of 383 patients

AIM

The concept of significant polyps and early colorectal cancer (SPECC) encompasses complex polyps not amenable to routine snare polypectomy or where malignancy cannot be excluded. Surgical resection (SR) offers definitive treatment, but is overtreatment for the majority which are benign and amenable to less invasive endoscopic resection (ER). The aim of this study was to investigate variations in the management and outcomes of significant colorectal polyps.

METHOD

This was a retrospective observational study of significant colorectal polyps, defined as nonpedunculated lesions of ≥ 20 mm size, diagnosed across nine UK hospitals in 2014. Inclusion criteria were endoscopically or histologically benign polyps at biopsy.

RESULTS

A total of 383 patients were treated by primary ER (87.2%) or SR (12.8%). Overall, 108/383 (28%) polyps were detected in the Bowel Cancer Screening Programme (BCSP). Primary SR was associated with a significantly longer length of stay and major complications (P < 0.01). Of the ER polyps, 290/334 (86.8%) patients were treated without undergoing surgery. The commonest indication for secondary surgery was unexpected polyp cancer, and of these cases 60% had no residual cancer in the specimen. Incidence of unexpected cancer was 10.7% (n = 41) and was similar between ER and SR groups (P = 0.11). On multivariate analysis, a polyp size of > 30 mm and non-BCSP status were independent risk factors for primary SR [OR 2.51 (95% CI 1.08-5.82), P = 0.03].

CONCLUSION

ER is safe and feasible for treating significant colorectal polyps. Robust accreditation within the BCSP has led to improvements in management, with lower rates of SR compared with non-BCSP patients. Standardization, training in polyp assessment and treatment within a multidisciplinary team may help to select appropriate treatment strategies and improve outcomes.

Clinical outcomes of endoscopic resection for colorectal laterally spreading tumors with advanced histology

BACKGROUND

Colorectal laterally spreading tumors (LSTs) are large, flat neoplasms that are usually treated using different endoscopic techniques based on their morphology, size, and histology. The aim of this study was to evaluate the clinical outcomes of LSTs with advanced histology treated by endoscopic resection.

METHODS

A total of 246 LSTs with advanced histology [i.e., high-grade dysplasia (HGD) and adenocarcinoma (AC)] treated by endoscopic resection [i.e., endoscopic mucosal resection (EMR), EMR-precutting (EMR-P), and endoscopic submucosal dissection (ESD)] were enrolled. Clinicopathological characteristics were collected by review of patient's medical records.

RESULTS

The en bloc resection and R0 resection rates were 75.6% and 85.0%, respectively. The bleeding and perforation rates were 10.2% and 2.4%, respectively. The frequency of cancerous pit pattern and bleeding was significantly higher in LSTs with AC than in LSTs with HGD. The R0 resection rate in LSTs with HGD was significantly higher than that in LSTs with AC. The frequency of cancerous pit patterns in LST cases with submucosal AC was significantly higher than those with intramucosal AC. The mean size of the LSTs was significantly larger in ESD group than in EMR or EMR-P groups. The frequencies of nodular mixed subtype, cancerous pit patterns, and en bloc resection rates were significantly higher in the ESD group than in the EMR or EMR-P groups. However, the frequency of perforation was significantly higher in EMR-P group than in EMR or ESD groups.

CONCLUSIONS

These results indicate that ESD is a more acceptable treatment approach for resection of colorectal LSTs of larger size, with nodular mixed subtype, having a cancerous pit pattern or AC, using either en bloc or curative resection methods, compared to EMR or EMR-P procedures.

Clinicopathological feature and treatment outcome of patients with colorectal laterally spreading tumors treated by endoscopic submucosal dissection

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is an advanced technique that can be used to treat precancerous and early colorectal neoplasms by facilitating en bloc resection regardless of tumor size. In our study, we investigated the clinicopathological feature and the treatment outcome of patients with colorectal laterally spreading tumors (LSTs) that were treated by ESD.

METHODS

The study enrolled all of 210 patients with colorectal LSTs who underwent ESD. Clinical outcomes were analyzed by retrospectively reviewing medical records.

RESULTS

A cancerous pit pattern (Vi/Vn) was more common in pseudo-depressed (PD) subtype than in flat elevated (FE) subtype. The incidence of adenocarcinoma in the PD subtype and nodular mixed (NM) subtypes was significantly higher than in the homogenous (HG) subtype and FE subtype. The en bloc and R0 resection rates were 89.0% and 85.7%, respectively. The bleeding and perforation rates were 5.2% and 1.9%, respectively. The mean procedure time was much longer in the PD subtype than in the FE subtype. The en bloc resection rate was significantly higher in the NM subtype than in the HG subtype. However, there were no statistically significant differences in mean procedure time, en bloc resection rate, R0 resection rate, bleeding rate, or perforation rate between LST-granular and LST-nongranular types.

CONCLUSIONS

These results indicate that ESD is acceptable for treating colorectal LSTs concerning en bloc resection, curative resection, and risk of complications. Careful consideration is required for complete resection of the PD subtype and NM subtype because of their higher malignant potential.

Endoscopic submucosal dissection of malignant non-pedunculated colorectal lesions

BACKGROUND AND STUDY AIMS

 Endoscopic submucosal dissection (ESD) is an established method for en bloc resection of large non-pedunculated colorectal lesions in Asia but dissemination of ESD in Western countries is limited. The aim of this study was to evaluate the role of ESD in the management of malignant non-pedunculated colorectal lesions in a European center.

PATIENTS AND METHODS

Among 255 patients undergoing colorectal ESD between 2014 and 2016, 29 cases were identified as submucosal invasive cancers and included in this study. The main outcomes were en bloc, R0 and curative resection as well as procedural time, complications and recurrence.

RESULTS

Median tumor size was 40 mm (range 20 - 70 mm). Thirteen cancers were located in the colon and 16 were located in the rectum. Procedural time was 89 minutes (range 18 - 594 minutes). Complete resection was achieved in 28 cases, en bloc and R0 resection rates were 83 % and 69 %, respectively. Curative resection rate was 38 %. One case had a perforation in the sigmoid colon requiring emergency surgery. No significant bleeding occurred. Six patients underwent additional surgery after ESD, one of whom had residual tumor. One recurrence was detected in 20 patients that were followed-up endoscopically, median follow-up time was 13 months (range 2 - 30 months).

CONCLUSION

ESD seems to be a safe and effective method for treating non-pedunculated malignant colorectal lesions after careful patient selection and proper endoscopic training.

Antigravity ESD - double-balloon-assisted underwater with traction hybrid technique

BACKGROUND AND STUDY AIMS

 Complex colorectal polyps or those positioned in difficult anatomic locations are an endoscopic therapeutic challenge. Underwater endoscopic submucosal dissection (UESD) is a potential technical solution to facilitate efficient polyp removal. In addition, endoscopic tissue retraction has been confined to limited methods of varying efficacy and complexity. The aim of this study was to evaluate the efficiency of a unique UESD technique for removing complex polyps using double-balloon-assisted retraction (R).

MATERIALS AND METHODS

 Using fresh ex-vivo porcine rectum, 4-cm polyps were created using electrosurgery and positioned at "6 o'clock" within an established ESD model. Six resections were performed in each group. Underwater techniques were facilitated using a novel double-balloon platform (Dilumen, Lumendi, Westport, Connecticut, United States).

RESULTS

 UESD-R had a significantly shorter total procedural time than cap-assisted ESD and UESD alone (24 vs. 58 vs. 56 mins). UESD-R produced a dissection time on average of 5 minutes, attributed to the retraction provided. There was also a subjective significant reduction in electrosurgical smoke with the underwater techniques contributing to improved visualization.

CONCLUSIONS

 Here we report the first ex-vivo experience of a unique double-balloon endoscopic platform optimized for UESD with tissue traction capability. UESD-R removed complex lesions in significantly shorter time than conventional means. The combined benefits of UESD and retraction appeared to be additive when tackling complex polyps and should be studied further.

Specialist Endoscopists Are Associated with a Decreased Risk of Incomplete Polyp Resection During Endoscopic Mucosal Resection in the Colon

BACKGROUND

Endoscopic experience is known to correlate with outcomes of endoscopic mucosal resection (EMR), particularly complete resection of the polyp tissue. Whether specialist endoscopists can protect against incomplete polypectomy in the setting of known risk factors for incomplete resection (IR) is unknown.

AIMS

We aimed to characterize how specialist endoscopists may help to mitigate the risk of IR of large sessile polyps.

METHODS

This is a retrospective cohort study of patients who underwent EMR at the University of Michigan from January 1, 2006, to November 15, 2015. The primary outcome was endoscopist-reported polyp tissue remaining at the end of the initial EMR attempt. Specialist endoscopists were defined as endoscopists who receive tertiary referrals for difficult colonoscopy cases and completed at least 20 EMR colonic polyp resections over the study period.

RESULTS

A total of 257 patients with 269 polyps were included in the study. IR occurred in 40 (16%) cases. IR was associated with polyp size ≥ 40 mm [adjusted odds ratio (aOR) 3.31, 95% confidence interval (CI) 1.38-7.93], flat/laterally spreading polyps (aOR 2.61, 95% CI 1.24-5.48), and difficulty lifting the polyp (aOR 11.0, 95% CI 2.66-45.3). A specialist endoscopist performing the initial EMR was protective against IR, even in the setting of risk factors for IR (aOR 0.13, 95% CI 0.04-0.41).

CONCLUSIONS

IR is associated with polyp size ≥ 40 mm, flat and/or laterally spreading polyps, and difficulty lifting the polyp. A specialist endoscopist initiating the EMR was protective of IR.

Colorectal endoscopic mucosal resection (EMR)

Colonoscopy has the benefit of detecting and treating precancerous adenomatous polyps and thus reduces mortality associated with CRC. Screening colonoscopy is the keystone for prevention of colorectal cancer. Over the last 20 years there has been increased in the management of large colorectal polyps from surgery to endoscopic removal techniques which is less invasive. Traditionally surgical resection was the treatment of choice for many years for larger polyps but colectomy poses significant morbidity of 14-46% and mortality of up to 7%. There are several advantages of endoscopic resection technique over surgery; it is less invasive, less expensive, has rapid recovery, and preserves the normal gut functions. In addition patient satisfaction and efficacy of EMR is higher with minor complications. Thus, this has facilitated the development of advanced resection technique for the treatment of large colorectal polyps called as endoscopic mucosal resection (EMR).

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.