Endoscopic therapy of stoma closure site strictures in ileal pouches is safe and effective.

Background: Strictures are a common complication after ileal pouch surgery with the most common locations being at the anastomosis, pouch inlet, and stoma closure site. No previous literature has described endoscopic therapy of stoma site stricture. This study aimed to assess the safety and efficacy of endoscopic therapy in the treatment of stoma closure site strictures. Method: Patients diagnosed with stoma closure site strictures following ileal pouch surgery who underwent endoscopic treatment at the Center for Colorectal Diseases, Inflammatory Bowel Disease (IBD), and Ileal Pouch between 2018 and 2022 were analysed. Primary outcomes (technical success and surgery-free survival) were compared between endoscopic balloon dilation (EBD) and stricturotomy and/or strictureplasty. Results: A total of 30 consecutive eligible patients were analysed. Most patients were female (66.7%) and most patients were diagnosed with IBD (93.3%). Twenty patients (66.7%) had end-to-end anastomosis. A total of 52 procedures were performed, with EBD in 16 (30.8%) and stricturotomy and/or strictureplasty in 36 (69.2%). The mean stricture length was 1.7 ± 1.0 cm. Immediate technical success was achieved in 47 of 52 interventions (90.4%). During a mean follow-up of 12.7 ± 9.9 months, none of the patients underwent surgical intervention for the stricture. Fourteen (46.7%) required endoscopic re-intervention for their strictures with an interval between index and re-interventional pouchoscopy of 8.8 ± 6.3 months. Post-procedural complications were reported in 2 (6.7%) with bleeding and none with perforation. Upon follow-up, 20 (66.7%) patients reported improvement in their symptoms. Conclusion: EBD and endoscopic stricturotomy and/or strictureplasty are safe and effective in treating stoma closure site strictures in patients with ileal pouches, providing symptomatic relief in most patients as well as avoiding surgery.

Insulated tip/needle-knife endoscopic stricturotomy is safe and effective for treatment of non-traversable anorectal strictures.

Background and study aims The treatment of anorectal strictures is particularly challenging and historically focused on surgical resection and/or diversion. There are a number of endoscopic options, but repeat interventions are common. The use of the needle knife stricturotomy technique as an alternative to surgery in the treatment of a variety of strictures has been described, but its use for the treatment of severe anorectal and anopouch strictures has not been studied. Patients and methods Our Inflammatory Bowel Disease department's records were queried to identify patients with endoscopic non-traversable anorectal/anopouch strictures. Consecutive patients that underwent insulated tip/needle-knife endoscopic stricturotomy treatment were included. Primary outcome was immediate traversability of the treated stricture by the endoscope. Other outcomes included need for reintervention, 30-day post-procedure events, and follow-up period events. Results All strictures were immediately successfully traversed following endoscopic stricturotomy treatment. The mean time to endoscopic reintervention was 5.3 months, with the majority of these patients undergoing repeat stricturotomy. Over a mean follow-up period of 12.8 months, two patients (8%) required surgical intervention (resection with coloanal anastomosis with a colostomy and complete proctectomy) for refractory stricture disease following initial endoscopic stricturotomy. Seven patients (29%) in our study have not required any further reintervention throughout the study period. There were no 30-day post-procedure adverse events and no adverse post-procedure events. Conclusions Endoscopic stricturotomy is safe and effective in treating severe anorectal/anopouch strictures.

Correction: Insulated tip/needle-knife endoscopic stricturotomy is safe and effective for treatment of non-traversable anorectal strictures.

[This corrects the article DOI: 10.1055/a-2230-7372.].

Conversion of Failed J-Pouch to Kock Pouch: Indications, Contraindications, and Outcomes.

BACKGROUND: The IPAA has been successful in restoring intestinal continuity and preserving continence in the majority of patients requiring a proctocolectomy. However, a subset of individuals experience significant complications that might result in pouch failure. The conversion of the J-pouch to a continent ileostomy pouch represents a significant surgical procedure. In this article, we discuss the indications and contraindications, present the technical principles applied for the conversion, and describe the outcomes of such conversion in the literature. OBJECTIVE: The main objective during the conversion of the J-pouch to a continent ileostomy is the creation of a sufficiently sized reservoir with a high-quality valve mechanism while preserving as much small bowel as possible. CONCLUSIONS: The conversion of the J-pouch to a continent ileostomy represents a significant surgical procedure. When performed in centers of expertise, it can be a good option for patients who otherwise will require an end ileostomy. Indications for conversion include most cases of J-pouch failure, with a few important exceptions. See video from symposium .

Application of enzyme-linked immunosorbent assay to detect antimicrobial peptides in human intestinal lumen.

Intestinal transplantation is the definitive treatment for intestinal failure. However, tissue rejection and graft-versus-host disease are relatively common complications, necessitating aggressive immunosuppression that can itself pose further complications. Tracking intraluminal markers in ileal effluent from standard ileostomies may present a noninvasive and sensitive way to detect developing pathology within the intestinal graft. This would be an improvement compared to current assessments, which are limited by poor sensitivity and specificity, contributing to under or over-immunosuppression, respectively, and by the need for invasive biopsies. Herein, we report an approach to reproducibly analyze ileal fluid obtained through stoma sampling for antimicrobial peptide/protein concentrations, reasoning that these molecules may provide an assessment of intestinal homeostasis and levels of intestinal inflammation over time. Concentrations of lysozyme (LYZ), myeloperoxidase (MPO), calprotectin (S100A8/A9) and ß-defensin 2 (DEFB2) were assessed using adaptations of commercially available enzyme-linked immunosorbent assays (ELISAs). The concentration of α-defensin 5 (DEFA5) was assessed using a newly developed sandwich ELISA. Our data support that with proper preparation of ileal effluent specimens, precise and replicable determination of antimicrobial peptide/protein concentrations can be achieved for each of these target molecules via ELISA. This approach may prove to be reliable as a clinically useful assessment of intestinal homeostasis over time for patients with ileostomies.

Role of Microbiome in the Outcomes Following Surgical Repair of Perianal Fistula: Prospective Cohort Study Design and Preliminary Results.

BACKGROUND: Anal fistulae are common, predominantly cryptoglandular, and almost invariably require surgical treatment. Recurrences are common for procedures other than fistulotomy regardless of technique and adequacy of repair. Growing evidence supports the pivotal role of specific intestinal bacteria in anastomotic failures after bowel resection. Anal crypts harbor colonic microbiota suggesting that similar mechanisms to anastomotic healing might prevail after anal fistula repair and hence influence healing. This study aims at assessing the potential role of the intestinal microbiome in the clinical outcomes after surgical repair of cryptoglandular anal fistula. METHODS: This is a pilot prospective cohort study enrolling patients with anal fistula undergoing endoanal advancement flap. For microbiome analysis, stool samples are taken via rectal swab before the procedure; additionally, a portion of the fistula is collected intraoperatively after fistulectomy. Samples from groups with treatment failure are compared to samples from patients who healed after surgical repair. Alpha and beta diversities and differential abundance of microbial taxa are determined and compared between groups with DADA2 analytical pipeline. RESULTS: Five patients have been enrolled to date (one female, four male). At median follow-up of 6 months (2-11), one patient experienced disease recurrence at 3 months. DNA from the 5 rectal swab and tissue samples was extracted, showing increased relative abundance of Enterococcus faecalis in samples from the patient who developed a recurrent fistula but not in those without recurrence. CONCLUSION: These very preliminary data suggest that intestinal microbiome may represent a crucial determinant of the surgical outcomes after anal fistula surgery.

Self-adherence to post-colonoscopy consults in patients undergoing diagnostic colonoscopy: Findings from a cross-sectional, quantitative survey at a South African quaternary hospital.

Post-colonoscopy consults empower patients to make informed decisions around their subsequent treatment, and non-compliance with these consults ("no-shows") hinders disease management. There is a paucity in the literature regarding self-adherence to post-colonoscopy consults in resource-limited settings such as South Africa. An understanding of self-adherence to post-colonoscopy consults in this setting is required to establish whether improved interventions are needed, and what specific elements of self-adherence should be addressed with these interventions. The objective of this hypothesis-generating, cross-sectional, quantitative survey was to conduct a baseline assessment of cognitive, motivational, social, and behavioural variables related to self-adherence to post-colonoscopy consults in patients who underwent diagnostic colonoscopy at a South African quaternary hospital. The Adherence Determinants Questionnaire (ADQ) was administered in 47 patients to establish a baseline assessment of elements related to self-adherence to post-colonoscopy consults, including interpersonal aspects of care, perceived utility, severity, susceptibility, subjective norms, intentions, and supports/barriers. ADQ scores were transformed to a percentage of the maximum score for each element (100.0%). The overall mean transformed ADQ score was 57.8%. The mean transformed scores for specific ADQ components were as follows: subjective norms (40.8%), perceived severity (55.4%), perceived utility (56.6%), intentions (59.4%), supports/barriers (59.9%), interpersonal aspects (62.2%), and perceived susceptibility (65.9%). There were no statistically significant differences in overall mean transformed ADQ scores and individual ADQ elements across categories of participant age (p-values ranging between 0.180 and 0.949 when compared between participants ≤40 years and >40 years old), gender (p-values ranging between 0.071 and 0.946 when compared between males and females), and race (p-values ranging between 0.119 and 0.774 when compared between Black Africans and non-Black Africans). Our findings suggest a general need for appropriate interventions to improve self-adherence to post-colonoscopy consults in our setting.

A Transcriptome-Based Precision Oncology Platform for Patient-Therapy Alignment in a Diverse Set of Treatment-Resistant Malignancies.

Predicting in vivo response to antineoplastics remains an elusive challenge. We performed a first-of-kind evaluation of two transcriptome-based precision cancer medicine methodologies to predict tumor sensitivity to a comprehensive repertoire of clinically relevant oncology drugs, whose mechanism of action we experimentally assessed in cognate cell lines. We enrolled patients with histologically distinct, poor-prognosis malignancies who had progressed on multiple therapies, and developed low-passage, patient-derived xenograft models that were used to validate 35 patient-specific drug predictions. Both OncoTarget, which identifies high-affinity inhibitors of individual master regulator (MR) proteins, and OncoTreat, which identifies drugs that invert the transcriptional activity of hyperconnected MR modules, produced highly significant 30-day disease control rates (68% and 91%, respectively). Moreover, of 18 OncoTreat-predicted drugs, 15 induced the predicted MR-module activity inversion in vivo. Predicted drugs significantly outperformed antineoplastic drugs selected as unpredicted controls, suggesting these methods may substantively complement existing precision cancer medicine approaches, as also illustrated by a case study. SIGNIFICANCE: Complementary precision cancer medicine paradigms are needed to broaden the clinical benefit realized through genetic profiling and immunotherapy. In this first-in-class application, we introduce two transcriptome-based tumor-agnostic systems biology tools to predict drug response in vivo. OncoTarget and OncoTreat are scalable for the design of basket and umbrella clinical trials. This article is highlighted in the In This Issue feature, p. 1275.

Surgery for Crohn's disease: upfront or last resort?

Crohn's disease (CD) can involve the entire gastrointestinal tract from the mouth to the anus and can lead to a constellation of symptoms. With the advancement of effective medical treatments for CD, a tendency has emerged to consider surgical treatment as a last resort. This potentially has the disadvantage of delaying surgery and if it fails might leave patients sicker, less well nourished, and with more severe complications. As with most non-malignant diseases, the choice of surgery vs medical treatment is a patient's personal preference under the guidance of the treating physician, except in extreme situations where surgery might be the only option. In this article, we will discuss the available evidence regarding the optimal timing of surgery in CD, focusing on whether early surgery can bring benefits in terms of disease control, symptom relief, and quality of life.

Management of pouch neoplasia: consensus guidelines from the International Ileal Pouch Consortium.

Surveillance pouchoscopy is recommended for patients with restorative proctocolectomy with ileal pouch-anal anastomosis in ulcerative colitis or familial adenomatous polyposis, with the surveillance interval depending on the risk of neoplasia. Neoplasia in patients with ileal pouches mainly have a glandular source and less often are of squamous cell origin. Various grades of neoplasia can occur in the prepouch ileum, pouch body, rectal cuff, anal transition zone, anus, or perianal skin. The main treatment modalities are endoscopic polypectomy, endoscopic ablation, endoscopic mucosal resection, endoscopic submucosal dissection, surgical local excision, surgical circumferential resection and re-anastomosis, and pouch excision. The choice of the treatment modality is determined by the grade, location, size, and features of neoplastic lesions, along with patients' risk of neoplasia and comorbidities, and local endoscopic and surgical expertise.

Feasibility and Safety of Ambulatory Surgery as the Next Management Paradigm in Colorectal Resection Surgery.

BACKGROUND: Current clinical dogma favors universal inpatient admission after colorectal resection particularly in the presence of an anastomosis. OBJECTIVE: We evaluate the feasibility and safety of ambulatory surgery in carefully selected patients undergoing colorectal resection/anastomosis. METHODS: Between October 2020 and October 2021, all patients undergoing colorectal resection/anastomosis meeting specific criteria {no major comorbidity [American Society of Anesthesiologist (ASA) <4], not on therapeutic anticoagulation, compliant patient/family} were counseled preoperatively for ambulatory surgery (discharge <24 h postsurgery). Complicated surgery (ileoanal pouch, enterocutaneous fistula repair, reoperative pelvic surgery, multiple resections) and/or ostomy creation (loop/end ileostomy, Hartmann's, abdominoperineal resection) were exclusions. Discharge was at 6 to 8 hours postoperatively if all predetermined factors (no ostomy teaching needed, ambulating comfortably, tolerating diet, stable vitals, and blood-work) were met and patients were willing, or was postponed to the next day at patient request. All discharged patients received phone checks the next day with the option also given for voluntary readmission if inpatient care was preferred by patient. Patients discharged <24 hours postop (AmbC) were compared to those staying on as inpatients admitted (InpC) and also to a comparable historical (October 2019-October 2020) group when ambulatory surgery was not offered (HistC). RESULTS: Of 184 abdominal colorectal surgery patients, 97 had complicated colorectal resection and/or ostomy. Of the remaining 87, 29 (33.3%) were discharged <24 hours postoperatively [7 (24%) patients at 8 h]. Of these 29 AmbC patients, 4 were readmitted <30 days (ileus: 1, rectal bleeding: 2, nausea/vomiting: 1), 1 readmission was on first postdischarge day, none were voluntary post phone-check. AmbC and InpC (n=58) had similar age, sex, race, body mass index, and comorbidity. InpC had greater estimated blood loss (109 vs 34 mL, P <0.001) while length of stay was expectedly significantly longer (109 vs 17 hours, P <0.001). There was no mortality in either group. AmbC and InpC had similar readmission, reoperation, anastomotic leak, ileus, and surgical site infection. Mean length of stay for HistC was 83 hours. AmbC and HistC had similar age, sex, race, body mass index, and ASA class. Complications including readmission, reoperation, anastomotic leak, ileus, and surgical site infection were also similar for AmbC and HistC. CONCLUSIONS: With careful patient selection, preoperative education, perioperative management, and postoperative follow-up, ambulatory surgery is feasible in up to a third of patients undergoing colorectal resection/anastomosis and can be performed with comparable safety to the time-honored practice of routine inpatient hospitalization. Refinements in inclusion/exclusion criteria and postoperative outpatient follow-up will allow a paradigm shift in how such patients are managed, which has huge implications for patient experience, care-giver workload and health care finances.

Multiplexed single-cell analysis reveals prognostic and nonprognostic T cell types in human colorectal cancer.

Clinical outcomes in colorectal cancer (CRC) correlate with T cell infiltrates, but the specific contributions of heterogenous T cell types remain unclear. To investigate the diverse function of T cells in CRC, we profiled 37,931 T cells from tumors and adjacent normal colon of 16 patients with CRC with respect to transcriptome, TCR sequence, and cell surface markers. Our analysis identified phenotypically and functionally distinguishable effector T cell types. We employed single-cell gene signatures from these T cell subsets to query the TCGA database to assess their prognostic significance. We found 2 distinct cytotoxic T cell types. GZMK+KLRG1+ cytotoxic T cells were enriched in CRC patients with good outcomes. GNLY+CD103+ cytotoxic T cells with a dysfunctional phenotype were not associated with good outcomes, despite coexpression of CD39 and CD103, markers that denote tumor reactivity. We found 2 distinct Treg subtypes associated with opposite outcomes. While total Tregs were associated with good outcomes, CD38+ Tregs were associated with bad outcomes independently of stage and possessed a highly suppressive phenotype, suggesting that they inhibit antitumor immunity in CRC. These findings highlight the potential utility of these subpopulations in predicting outcomes and support the potential for novel therapies directed at CD38+ Tregs or CD8+CD103+ T cells.

Association Between Portal Vein Thrombosis and Pouchitis in Patients with Ulcerative Colitis.

BACKGROUND: Pouchitis is the most common long-term complication in patients requiring colectomy ileal pouch-anal anastomosis with medically refractory ulcerative colitis or colitis-associated neoplasia. A previous small case series suggests associated between portal vein thrombosis (PVT) and ischemic pouchitis. AIM: To evaluate the association between PVT and other demographic and clinical factors and pouchitis. METHODS: We used Explorys Inc., a population-based database, to search medical records between 1999 and 2020 with SNOMED-CT code criteria for "construction of pouch" and "ileal pouchitis." Patients with pouchitis were compared to those with previous pouch construction without pouchitis. Factors associated with pouchitis identified with univariable analysis were introduced into a multivariable model. A post hoc analysis further stratified demographical findings of the association between PVT and pouchitis. RESULTS: We identified 7900 patients with ileal pouchitis (7.5%) and 97,510 with pouch construction without pouchitis. In multivariate binary logistic regression, adjusted odds ratio (aOR) for the risk of pouchitis in patients with PVT was 10.78 (95% confidence interval [CI] 7.04-16.49, P < 0.001). Other significant factors associated with pouchitis included male gender (aOR 1.11, 95% CI 1.02-1.21, P = 0.018), deep vein thrombosis (aOR 1.46, 95% CI 1.23-1.72, P < 0.001), and the use of non-steroidal anti-inflammatory drugs (aOR 1.37, 95% CI 1.28-1.45, P < 0.001). Smoking was a protective factor (aOR 0.30, 95% CI 0.33-0.36, P < 0.001). Further sub-analysis showed a higher prevalence of younger patients with PVT and pouchitis. CONCLUSIONS: We report PVT as an independent risk factor associated with pouchitis. Our findings support that PVT is a potentially manageable perioperative complication, and intervention may reduce the risk of pouchitis.

Treatment of pouchitis, Crohn's disease, cuffitis, and other inflammatory disorders of the pouch: consensus guidelines from the International Ileal Pouch Consortium.

Pouchitis, Crohn's disease of the pouch, cuffitis, polyps, and extraintestinal manifestations of inflammatory bowel disease are common inflammatory disorders of the ileal pouch. Acute pouchitis is treated with oral antibiotics and chronic pouchitis often requires anti-inflammatory therapy, including the use of biologics. Aetiological factors for secondary pouchitis should be evaluated and managed accordingly. Crohn's disease of the pouch is usually treated with biologics and its stricturing and fistulising complications can be treated with endoscopy or surgery. The underlying cause of cuffitis determines treatment strategies. Endoscopic polypectomy is recommended for large, symptomatic inflammatory polyps and polyps in the cuff. The management principles of extraintestinal manifestations of inflammatory bowel disease in patients with pouches are similar to those in patients without pouches.

Impact of Intraoperative Data on Risk Prediction for Mortality After Intra-Abdominal Surgery.

BACKGROUND: Risk prediction models for postoperative mortality after intra-abdominal surgery have typically been developed using preoperative variables. It is unclear if intraoperative data add significant value to these risk prediction models. METHODS: With IRB approval, an institutional retrospective cohort of intra-abdominal surgery patients in the 2005 to 2015 American College of Surgeons National Surgical Quality Improvement Program was identified. Intraoperative data were obtained from the electronic health record. The primary outcome was 30-day mortality. We evaluated the performance of machine learning algorithms to predict 30-day mortality using: 1) baseline variables and 2) baseline + intraoperative variables. Algorithms evaluated were: 1) logistic regression with elastic net selection, 2) random forest (RF), 3) gradient boosting machine (GBM), 4) support vector machine (SVM), and 5) convolutional neural networks (CNNs). Model performance was evaluated using the area under the receiver operator characteristic curve (AUROC). The sample was randomly divided into a training/testing split with 80%/20% probabilities. Repeated 10-fold cross-validation identified the optimal model hyperparameters in the training dataset for each model, which were then applied to the entire training dataset to train the model. Trained models were applied to the test cohort to evaluate model performance. Statistical significance was evaluated using P < .05. RESULTS: The training and testing cohorts contained 4322 and 1079 patients, respectively, with 62 (1.4%) and 15 (1.4%) experiencing 30-day mortality, respectively. When using only baseline variables to predict mortality, all algorithms except SVM (area under the receiver operator characteristic curve [AUROC], 0.83 [95% confidence interval {CI}, 0.69-0.97]) had AUROC >0.9: GBM (AUROC, 0.96 [0.94-1.0]), RF (AUROC, 0.96 [0.92-1.0]), CNN (AUROC, 0.96 [0.92-0.99]), and logistic regression (AUROC, 0.95 [0.91-0.99]). AUROC significantly increased with intraoperative variables with CNN (AUROC, 0.97 [0.96-0.99]; P = .047 versus baseline), but there was no improvement with GBM (AUROC, 0.97 [0.95-0.99]; P = .3 versus baseline), RF (AUROC, 0.96 [0.93-1.0]; P = .5 versus baseline), and logistic regression (AUROC, 0.94 [0.90-0.99]; P = .6 versus baseline). CONCLUSIONS: Postoperative mortality is predicted with excellent discrimination in intra-abdominal surgery patients using only preoperative variables in various machine learning algorithms. The addition of intraoperative data to preoperative data also resulted in models with excellent discrimination, but model performance did not improve.

Predictors of treatment refusal in patients with colorectal cancer: A systematic review.

This systematic review was conducted to investigate predictors of treatment refusal in colorectal cancer (CRC) patients. An understanding of these predictors would inform statistical models for the identification of high-risk patients who might benefit from interventions that seek to improve treatment compliance. We performed a search of PubMed and Scopus to identify potentially relevant studies on predictors of treatment refusal in CRC patients that were published between January 1, 2000 and December 31, 2021. We screened manuscripts using predefined eligibility criteria. Information on study design, study location, patient characteristics, treatments, rates and predictors of treatment refusal, and the impact of treatment refusal on mortality or survival were collected from eligible studies. Study quality was assessed using the Newcastle-Ottawa score. The overall findings of the review process were summarized using descriptive statistics and a narrative synthesis. A total of 13 studies were included in this review. Ten studies reported on refusal of CRC surgery, refusal rate: 0.25%-3.26%; three studies reported on chemotherapy refusal (one of which reported on both surgery and chemotherapy refusal), refusal rate: 7.8%-41.5%; and one study reported on refusal of any cancer treatment, refusal rate: 8.7%. The bulk of the published literature confirmed the harmful association between treatment refusal and poor survival outcomes in CRC patients. Frequently cited predictors of treatment refusal included patient demographic characteristics (age, race, gender), clinical characteristics (disease stage, comorbidity), and factors that impact access to cancer care services (healthcare insurance, facility level). Potentially high rates of treatment refusal pose a challenge to CRC control. This review has identified several factors which must be considered when attempting to reduce treatment refusal in CRC patients. Furthermore, these factors should be tested as components of predictive risk models for this important outcome.

Diagnosis and classification of ileal pouch disorders: consensus guidelines from the International Ileal Pouch Consortium.

Restorative proctocolectomy with ileal pouch-anal anastomosis is an option for most patients with ulcerative colitis or familial adenomatous polyposis who require colectomy. Although the construction of an ileal pouch substantially improves patients' health-related quality of life, the surgery is, directly or indirectly, associated with various structural, inflammatory, and functional adverse sequelae. Furthermore, the surgical procedure does not completely abolish the risk for neoplasia. Patients with ileal pouches often present with extraintestinal, systemic inflammatory conditions. The International Ileal Pouch Consortium was established to create this consensus document on the diagnosis and classification of ileal pouch disorders using available evidence and the panellists' expertise. In a given individual, the condition of the pouch can change over time. Therefore, close monitoring of the activity and progression of the disease is essential to make accurate modifications in the diagnosis and classification in a timely manner.

Predictors of Positive Circumferential Resection Margin in Rectal Cancer: A Current Audit of the National Cancer Database.

BACKGROUND: Positive circumferential resection margin is a predictor of local recurrence and worse survival in rectal cancer. National programs aimed to improve rectal cancer outcomes were first created in 2011 and continue to evolve. The impact on circumferential resection margin during this time frame has not been fully evaluated in the United States. OBJECTIVE: The purpose of this study was to determine the incidence and predictors of positive circumferential resection margin after rectal cancer resection, across patient, provider, and tumor characteristics. DESIGN: This was a retrospective cohort study. SETTINGS: The study was conducted using the National Cancer Database, 2011-2016. PATIENTS: Adults who underwent proctectomy for pathologic stage I to III rectal adenocarcinoma were included. MAIN OUTCOME MEASURES: Rate and predictors of positive circumferential resection margin, defined as resection margin ≤1 mm, were measured. RESULTS: Of 52,620 cases, circumferential resection margin status was reported in 90% (n = 47,331) and positive in 18.4% (n = 8719). Unadjusted analysis showed that patients with positive circumferential resection margin were more often men, had public insurance and shorter travel, underwent total proctectomy via open and robotic approaches, and were treated in Southern and Western regions at integrated cancer networks (all p < 0.001). Multivariate analysis noted that positive proximal and/or distal margin on resected specimen had the strongest association with positive circumferential resection margin (OR = 15.6 (95% CI, 13.6-18.1); p < 0.001). Perineural invasion, total proctectomy, robotic approach, neoadjuvant chemoradiation, integrated cancer network, advanced tumor size and grade, and Black race had increased risk of positive circumferential resection margin (all p < 0.050). Laparoscopic approach, surgery in North, South, and Midwest regions, greater hospital volume and travel distance, lower T-stage, and higher income were associated with decreased risk (all p < 0.028). LIMITATIONS: This was a retrospective cohort study with limited variables available for analysis. CONCLUSIONS: Despite creation of national initiatives, positive circumferential resection margin rate remains an alarming 18.4%. The persistently high rate with predictors of positive circumferential resection margin identified calls for additional education, targeted quality improvement assessments, and publicized auditing to improve rectal cancer care in the United States. See Video Abstract at http://links.lww.com/DCR/B584. PREDICTORES PARA UN MARGEN POSITIVO DE RESECCIN CIRCUNFERENCIAL EN EL CNCER DE RECTO UNA AUDITORA VIGENTE DE LA BASE DE DATOS NACIONAL DE CANCER: ANTECEDENTES:El margen positivo de resección circunferencial es un predictor de recurrencia local y peor sobrevida en el cáncer de recto. Los programas nacionales destinados a mejorar los resultados del cáncer de recto se crearon por primera vez en 2011 y continúan evolucionando. La repercusión del margen de resección circunferencial durante este período de tiempo no se ha evaluado completamente en los Estados Unidos.OBJETIVO:Determinar la incidencia y los predictores para un margen positivo de resección circunferencial posterior a la resección del cáncer de recto, según las características del paciente, el proveedor y el tumor.DISEÑO:Estudio de cohorte retrospectivo.AMBITO:Base de datos nacional de cáncer, 2011-2016.PACIENTES:Adultos que se sometieron a proctectomía por adenocarcinoma de recto con un estadío por patología I-III.PRINCIPALES VARIABLES EVALUADAS:Tasa y predictores para un margen positivo de resección circunferencial, definido como margen de resección ≤ 1 mm.RESULTADOS:De 52,620 casos, la condición del margen de resección circunferencial se informó en el 90% (n = 47,331) y positivo en el 18.4% (n = 8,719). El análisis no ajustado mostró que los pacientes con margen positivo de resección circunferencial se presentó con mayor frecuencia en hombres, tenían un seguro social y viajes más cortos, se operaron de proctectomía total abierta y robótica, y fueron tratados en las regiones del sur y el oeste en redes integradas de cáncer (todos p <0,001). El análisis multivariado destacó que el margen proximal y / o distal positivo de la pieza resecada tenía la asociación más fuerte con el margen postivo de resección circunferencial (OR 15,6; IC del 95%: 13,6-18,1, p <0,001). La invasión perineural, la proctectomía total, el abordaje robótico, la quimioradioterapia neoadyuvante, la red de cáncer integrada, el tamaño y grado del tumor avanzado y la raza afroamericana tenían un mayor riesgo de un margen de una resección positiva circunferencial (todos p <0,050). El abordaje laparoscópico, la cirugía en las regiones Norte, Sur y Medio Oeste, un mayor volumen hospitalario y distancia de viaje, estadio T más bajo y mayores ingresos se asociaron con una disminución del riesgo (todos p <0,028).LIMITACIONES:Estudio de cohorte retrospectivo con variables limitadas disponibles para análisis.CONCLUSIONES:A pesar del establecimiento de iniciativas nacionales, la tasa de margen positivo de resección circunferencial continúa siendo alarmante, 18,4%. El índice continuamente elevado junto a los predictores de un margen positivo de resección circunferencial hace un llamado para una mayor educación, evaluaciones específicas de mejora de la calidad y difusión de las auditorías para mejorar la atención del cáncer de recto en los Estados Unidos. Vea el resumen de video en http://links.lww.com/DCR/B584. Consulte Video Resumen en http://links.lww.com/DCR/B584.