Dozois, Eric J.

Abstract Background Presacral tumours are rare, heterogeneous lesions. Historical classification systems for presacral tumours have provided a valuable framework, but were based on limited available data. This study aimed to develop a contemporary classification aligned with current tumour entities and clinical practice. Methods A prospectively registered systematic review of surgically managed presacral tumours published from 1975 to 2025 was combined with a retrospective multisite institutional surgical pathology review from 1986 to 2025. Pathological descriptors were extracted, cross-referenced, harmonized to current terminology, and organized through multidisciplinary expert review to obtain a new classification. Results The systematic review identified 5997 records, of which 203 studies met the inclusion criteria and contributed 181 pathological terms after generic and unclassifiable diagnoses were removed. Review of 3606 pathology reports identified 19 additional terms, bringing the total to 200 pathological terms. After harmonization to current terminology and exclusion of non-neoplastic processes, a contemporary classification was developed using biological descriptors: developmental versus acquired origin; tissue lineage (neurogenic, osseous/haematopoietic, soft tissue, or miscellaneous); and tumour behaviour (benign, locally recurrent without metastatic potential, locally recurrent with low metastatic potential, malignant non-sarcoma, or malignant sarcoma). Conclusion The Mayo Clinic classification of presacral tumours updates historical systems by reflecting the broader, more modern spectrum of neoplasms and distinguishing lesions by lineage and biological behaviour. It may improve diagnostic clarity, communication, and selection of appropriate observation, multidisciplinary assessment, and treatment pathways.

Abstract This literature‐based systematic review and associated guidelines provide evidence‐based paradigms for the management of locoregionally recurrent rectal cancer (LRRC). This multispecialty committee included gastrointestinal radiation and medical oncology, gastroenterology, radiology, and colorectal surgery. As is the standard, the previously described American Radium Society Appropriate Use Criteria methodology for this project was followed rigorously, with the Population, Intervention, Comparator, Outcome, Timing, and Study Design framework and Preferred Reporting Items for Systematic Reviews and Meta‐Analyses methodology to assess the evidence. RAND/University of California Los Angeles consensus methodology (modified Delphi) was used to rate the appropriateness of treatment options. Published between January 1, 2013, and July 16, 2025, 116 peer‐reviewed trials provided the evidence: 10 were well‐designed randomized phase 2/3 trials, 29 were moderately well designed trials that accounted for most common biases (matched cohort and phase 2), 76 trials had design limitations (retrospective), and one was a meta‐analysis. Clinical cases were created as examples to illustrate current acceptable management of LRRC. Treatment and prognosis are influenced by prior therapy and the site(s) and extent of LRRC. The ability to achieve a margin‐negative surgical resection is the ultimate determinant of survival and local control. Preoperative systemic therapy, radiation therapy, or a combination of the two can facilitate tumor downsizing and improve the likelihood of a margin‐negative resection. An individualized multidisciplinary approach is required to ensure the best outcome. Although this review does not suggest a major alteration of current practice, it provides reassuring evidence of the importance of combined‐modality therapy.

Importance Rectovaginal fistulas (RVFs) are challenging to treat, often requiring multiple surgical interventions. Research into novel therapies is limited by the lack of a sizeable and representative animal model. Given the similarities in porcine and human vaginal and rectal tissue, pigs are an ideal species for translation to human patients. Objective The objective of this study was to develop a feasible and reproducible RVF model in pigs. Study Design Six female pigs underwent RVF creation and were divided into 3 groups according to the following methods: (1) placement of 1-inch disc magnets across the rectovaginal septum, (2) a 1-inch round defect created using electrocautery and placement of a 1-inch stainless-steel gauge stent, (3) a 1-inch round defect using electrocautery without subsequent stenting. Fistulas were evaluated at 6 weeks with measurements and photographic documentation. The animals were euthanized between 12 and 14 weeks. The primary outcome of this study was fistula patency. Secondary outcomes were fistula dimension and histologic appearance of the fistula tract. Results All pigs did well with no infection or complications related to fistula creation. Both surgical methods reliably resulted in a patent fistula at 14 weeks: cautery alone and cautery with gauge stenting. Only 1 patent fistula in the magnet group was noted at the time of euthanasia. All patent fistulas showed histologic evidence of complete epithelialization of the fistula tract. Conclusions This study demonstrates 3 safe and feasible methods for RVF creation in pigs, with 2 methods showing increased reliability.

Abstract Background Presacral tumours are rare and heterogeneous lesions arising within a complex anatomical space, resulting in variability in diagnosis and management. Increasing incidental detection and evolving surgical and oncological strategies have highlighted the need for contemporary guidance. The aim of this study was to establish an international expert consensus on the optimal diagnosis and management of presacral tumours. Methods An international panel of colorectal surgeons from high-volume units was convened. Evidence- and practice-based statements were developed after domain-based literature reviews and refined through five online and two in-person meetings. Consensus was achieved using a modified Delphi process with anonymous voting. Results In total, 16 colorectal surgeons participated in the study. Ten domains were identified resulting in the development of 22 statements based on expert opinion and retrospective studies. After two rounds, unanimous (100%) agreement was achieved for all statements. High-resolution MRI with structured synoptic reporting is endorsed as central to risk stratification. Selective image-guided transperineal or parasacral biopsy is recommended for high-risk lesions where histology would alter management. Complete surgical resection is defined as the operative goal, with approach tailored to tumour biology and anatomy; minimally invasive surgery is considered appropriate in selected cases. Non-operative surveillance is supported for carefully selected asymptomatic, low-risk cystic lesions. Postoperative surveillance is recommended in a risk-adapted manner according to histopathology and margin status. Conclusion This international consensus provides a pragmatic, risk-stratified framework for the multidisciplinary diagnosis and management of presacral tumours. These recommendations aim to reduce practice variation, support decision-making in specialized centres, and inform future prospective collaborative research.

INTRODUCTION: Advanced therapies infrequently achieve complete fistula closure in patients with Crohn's disease (CD). The primary objective of the STOMP2 clinical trial was to determine whether the implantable autologous cell therapy AVB-114 is effective in inducing remission of persistent Crohn's perianal fistulas versus standard of care. METHODS: Eligible patients had a single perianal fistula tract and had failed previous treatment or had documented medication intolerance to biologic or conventional CD therapy. All enrolled subjects underwent surgical fistula optimization and adipose tissue biopsy collection (to manufacture AVB-114) followed by 1:1 randomization to either standard of care (repeat fistula optimization including seton replacement) or AVB-114 implantation. The primary end point was combined fistula remission at 36 weeks, defined as closure of the external opening, no drainage of fluid despite gentle finger compression, and no collections >2 cm in at least 2 of the 3 dimensions on MRI. RESULTS: Subjects at 14 US sites were equally randomized to SoC (N = 24) or AVB-114 (N = 24). Week 36 combined remission was 8.3% and 45.8% for subjects randomized to SoC and AVB-114, respectively (38% difference, 95% CI 11%–60%; P = 0.0078). At week 36, MRI revealed no subjects with collections >2 cm, radiological improvement (≥50% decrease in the Magnetic Resonance Novel Index for Fistula Imaging in Crohn's Disease (MAGNIFI-CD) score from baseline) in 1 SoC subject and 3 AVB-114 subjects, and radiological healing (complete resolution of T2-weighted hyperintensity in fistula tract) in 2 SoC subjects and 5 AVB-114 subjects. Through week 36, there were 40 and 56 treatment emergent adverse events for SoC and AVB-114, respectively. There were no serious treatment emergent adverse events in the AVB-114 group through week 36. DISCUSSION: A significantly higher proportion of patients treated with AVB-114 achieved combined remission vs SoC, and the treatment was well tolerated. These data support the safety and efficacy of AVB-114 in persistent Crohn's perianal fistulas.

Objectives: To summarize recent high-quality trials and provide an update to the original 2022 American College of Radiology Appropriate Use Criteria for Treatment of Locoregional Gastric Adenocarcinoma. This multi-specialty-led committee included gastrointestinal radiation and medical oncology, gastroenterology, radiology, and surgical oncology. Methods: Using the population, intervention, comparator, outcome, timing, and study design framework, the evidence was assessed using Cochrane and PRISMA 2020 methodology. Eligible studies included prospective Phase II/II trials and select retrospective studies published between 5/1/2020 and 8/1/2025 in the Embase, Medline, and Pubmed databases. Study type and quality were assessed. Well-established RAND-UCLA consensus methodology (modified Delphi) was used to rate the appropriateness of the treatment options. Results: ARS AUC recommendations include adjuvant FLOT chemotherapy for localized gastric adenocarcinoma after neoadjuvant FLOT and surgery, poCT or perioperative chemoimmunotherapy for localized gastric adenocarcinoma, adjuvant chemotherapy +/− CRT for localized gastric adenocarcinoma that undergoes upfront surgery, and systemic therapy alone for localized gastric adenocarcinoma in a medically inoperable patient. Conclusions: This updated ARS AUC summary provides guidelines for the multimodality treatment of resectable gastric adenocarcinoma.

Abstract Background The STOMP2 trial sought to determine whether the implantable autologous cell therapy AVB-114 is an effective add-on therapy for patients with persistent Crohn’s perianal fistulas. The trial design incorporated wait-list controlled (WLC) elements, allowing eligible control group subjects who completed the 9 mo primary endpoint visit in Part 1 to request AVB-114 treatment in Part 2 and strengthen the evaluation of AVB-114’s safety and effectiveness. Methods Eligible patients had a single perianal fistula tract and had failed prior treatment or had documented medication intolerance to biologic or conventional Crohn’s disease therapy. Subjects at 14 U.S. sites were randomized 1:1 to either standard of care (SoC; fistula optimization including seton placement) or AVB-114 implantation. The primary endpoint was combined fistula remission at 9 mo, defined as no collections >2cm on MRI, visual closure of the external opening, and no drainage of fluid despite gentle finger compression. A logistic regression time from exposure model through 9 mo utilized complete Part 1 data and all available Part 2 data to estimate combined AVB-114 effectiveness. Results Part 1 combined remission (using Non-Responder Imputation) was 8.3% (2/24) for SoC and 45.8% (11/24) for AVB-114 (38% difference, 95% CI 11 – 60%, post-hoc p-value of 0.0078). Twenty SoC subjects were treated with AVB-114 in Part 2. Four of the 9 Part 2 subjects with 9 mo combined remission data available were in combined fistula remission (44.4%). No subjects failed 9 mo radiological remission (first component of the primary endpoint), thus clinical remission (composite of the latter two components) was equivalent to combined remission. AVB-114 clinical remission in Part 1 and Part 2 to-date were similar, and when combined provided narrower estimates with the same coverage (Figure 1). Mean (SD) 9 mo perianal disease activity index (PDAI) scores for SoC, Part 1 AVB-114, and Part 2 AVB-114 were 5.0 (2.6), 4.1 (2.9), and 3.8 (3.5), respectively. Lower 9 mo scores and decreases from baseline were independently associated with an increased probability of clinical remission. Two serious treatment-emergent adverse events (TEAEs; pseudopolyposis and proctalgia) occurred, with the latter attributed to AVB-114. Non-serious product related TEAE were predominantly related to postoperative perianal pain. Two grade 2 (moderate) AEs of cellulitis and abdominal wall abscess were attributed to adipose tissue collection. Conclusion Both the randomized and combined (all-treated) analyses demonstrated substantial AVB-114 effectiveness through 9 mo in this challenging patient population. AEs were anticipated, and generally mild and infrequent. Conflict of interest: Schwartz, David: 1) Abbvie: consultant 2) Janssen: Consultant 3) Takeda: Consultant 4) Avbios- consultant 5) Olympus- consultant Dozois, Eric: TBD Ehman, Eric: TBD Faubion, William: TBD Hudesman, David: Consultant: Avalo, Abbvie, Abivax, Biocon, BMS, CorEvitas, Eli Lilly, Johnson and Johnson, Pfizer, Prometheus, Sanofi, Takeda, Fresenius Kabi Research Support: Pfizer and Johnson and Johnson Espen, Benjamin: employee of Avobis Bio LLC Pabla, Baldeep: Astellas, J & J - Advisory Board Prometheus - Speaker Eli Lilly - Speaker Papadakis, Konstantinos: TBD

BACKGROUND: Pelvic exenteration is the treatment of choice for selected patients with locally advanced primary and recurrent rectal cancer. Involvement of major pelvic neurovascular structures and bone was historically considered a contraindication due to unacceptably high rates of morbidity and low R0 resection rates. OBJECTIVE: To compare the outcomes of these “high-complexity” exenterative resections to those of “conventional” pelvic exenteration. DESIGN: International multicenter retrospective cohort study. SETTINGS: Sixteen specialized exenteration centers. PATIENTS: Those who underwent total pelvic exenteration for locally advanced primary and recurrent rectal cancer between 2018 and 2023 at participating centers. MAIN OUTCOME MEASURES: Perioperative resource utilization, morbidity, mortality, and R0 resection rates were reported. RESULTS: Seven hundred sixty-three patients underwent total pelvic exenteration, of whom 478 (63%) and 285 (37%) required conventional and high-complexity procedures, respectively. High-complexity pelvic exenteration was associated with longer operating time (600 vs 480 minutes, p < 0.001 for locally advanced primary rectal cancer, 623 vs 480 minutes, p < 0.001 for locally recurrent rectal cancer), intensive care stay (2 vs 1 day, p < 0.001 and 3 vs 1 day, p < 0.001), hospital stay (19 vs 15 days, p = 0.008 and 23 vs 15 days, p < 0.001), and higher blood loss (2000 vs 1236 mL, p < 0.001 and 3000 vs 1600 mL, p < 0.001). Morbidity and mortality outcomes and R0 resection rates were similar between the groups. LIMITATIONS: Generalizability of findings outside of expert units. CONCLUSIONS: High-complexity pelvic exenteration for the treatment of rectal cancer is associated with similar morbidity, mortality, and R0 resection rates, but it has a significantly higher operative time, blood loss, and hospital resource utilization compared to conventional pelvic exenteration. In high-volume, specialized centers, these techniques are considered the standard of care for appropriately selected patients with tumors that involve major pelvic bone or neurovascular structures. See Video Abstract . EXENTERACIÓN PÉLVICA TOTAL CONVENCIONAL FRENTE A EXENTERACIÓN PÉLVICA TOTAL DE ALTA COMPLEJIDAD PARA EL CÁNCER RECTAL LOCALMENTE AVANZADO Y LOCALMENTE RECURRENTE: UN ESTUDIO MULTICÉNTRICO INTERNACIONAL ANTECEDENTES: La exenteración pélvica es el tratamiento de elección para determinados pacientes con cáncer rectal primario y recurrente localmente avanzado. La afectación de las principales estructuras neurovasculares y óseas pélvicas se consideraba históricamente una contraindicación debido a las tasas inaceptablemente altas de morbilidad y a las bajas tasas de resección R0. OBJETIVO: Comparar los resultados de estas resecciones exenteración «de alta complejidad» con los de la exenteración pélvica «convencional». DISEÑO: Estudio de cohorte retrospectivo multicéntrico internacional. ENTORNOS: Dieciséis centros especializados en exenteración. PACIENTES: Aquellos que se sometieron a una exenteración pélvica total por cáncer rectal primario y recurrente localmente avanzado entre 2018 y 2023 en los centros participantes. PRINCIPALES MEDIDAS DE RESULTADOS: Se informaron la utilización de recursos perioperatorios, la morbilidad, la mortalidad y las tasas de resección R0. RESULTADOS: 763 pacientes se sometieron a una exenteración pélvica total, de los cuales 478 (63 %) y 285 pacientes (37 %) requirieron procedimientos convencionales y de alta complejidad, respectivamente. La exenteración pélvica de alta complejidad se asoció con un tiempo quirúrgico más prolongado (600 frente a 480 minutos, p < 0,001 para el cáncer rectal primario localmente avanzado, 623 frente a 480 minutos, p < 0,001 para el cáncer rectal localmente recurrente), estancia en cuidados intensivos (2 frente a 1 día, p < 0,001 y 3 frente a 1 día, p < 0,001), estancia hospitalaria (19 frente a 15 días, p = 0,008 y 23 frente a 15 días, p < 0,001) y mayor pérdida de sangre (2000 frente a 1236 ml, p < 0,001 y 3000 frente a 1600 ml, p < 0,001). Los resultados de morbilidad y mortalidad, así como las tasas de resección R0, fueron similares entre los grupos. LIMITACIONES: Generalización de los resultados fuera de las unidades especializadas CONCLUSIONES: La exenteración pélvica de alta complejidad para el tratamiento del cáncer de recto se asocia con tasas similares de morbilidad, mortalidad y resección R0, pero con un tiempo quirúrgico, una pérdida de sangre y una utilización de recursos hospitalarios significativamente mayores en comparación con la exenteración pélvica convencional. En centros especializados con un gran volumen de casos, estas técnicas se consideran el tratamiento estándar para pacientes adecuadamente seleccionados con tumores que afectan a los huesos pélvicos principales o a las estructuras neurovasculares. ( AI-generated translation )

Abstract Background: Congenital peritoneal encapsulation (cocoon deformity) is a rare variant of intestinal malrotation. Objectives: To characterize the clinical presentation and outcomes in patients undergoing surgery for intestinal malrotation with cocoon deformity. Design: Retrospective review. Settings: A large tertiary care center, from January 2003 to December 2022. Patients and Methods: All patients who underwent surgery for intestinal malrotation with cocoon deformity were included. Sample Size: Nine patients were identified. Main Outcome Measures: Patient demographics and operative outcomes. Results: Most patients were female (88.9%), with a median age of 37 years (interquartile range [IQR], 19–53). Most were symptomatic upon diagnosis (88.9%), with abdominal pain (77.8%) being the most common symptom. One patient presented acutely, requiring immediate surgical intervention. Computed tomography was the most frequently used modality to establish a diagnosis of intestinal malrotation. A laparoscopic Ladd procedure was attempted in all patients, with three requiring conversion to open surgery. The median operative time was 119 min (IQR, 96.5–202), with a median estimated blood loss of 25 mL (IQR, 15–125). The median length of hospital stay was 2 days (IQR, 1.5–7). The most common postoperative complications were ileus ( n = 3, 33.3%) and 30-day readmission ( n = 3, 33.3%). Most patients experienced partial or complete resolution of symptoms ( n = 7, 77.8%) and no patients required reoperation. The median follow-up duration was 71.8 months (IQR, 21.3–138.7). Conclusions: The laparoscopic Ladd procedure with excision of the cocoon deformity can be performed safely and is associated with significant improvement in preoperative symptoms. Limitations: Cocoon deformity was not diagnosed preoperatively, and there is currently no gold standard imaging modality for its detection.

Objective: To determine if a Super Learner (SL) machine learning approach could improve the predictive accuracy of the American College of Surgeons Risk Calculator (ACS-RC) for postoperative complications in patients undergoing colorectal surgery. Summary of Background Data: Machine learning (ML) has shown significant potential to advance medical fields, including surgical risk prediction. Current tools, like the ACS-RC which uses logistic regression and extreme gradient boosting, are standard but may be enhanced by more advanced ML ensembles. Methods: This retrospective study analyzed colorectal surgery cases from the 2018-2022 ACS National Surgical Quality Improvement Program (NSQIP) database. An SL model, which combines multiple ML algorithms, was developed to predict fourteen postoperative outcomes. Its performance was compared against traditional logistic regression (LOG) and extreme gradient boosting (XGB) models. Key performance metrics included discrimination (AUROC, AUPRC) and calibration (Brier score, Hosmer-Lemeshow test). Results: The SL model demonstrated superior performance across all predicted complications when compared to both LOG and XGB. It showed superior discrimination for severe outcomes, achieving an AUROC greater than 0.94 for predicting mortality. The SL model was also more accurate in predicting infectious complications and length of stay, and its calibration metrics indicated a better overall fit and accuracy. Conclusions: The Super Learner model enhances the accuracy of postoperative risk prediction in colorectal surgery. Its superior performance suggests it is a promising tool for improving personalized patient counseling, aiding clinical decision-making, and optimizing resource allocation.