Thiels, Cornelius A.

Abstract Background Some centres advocate preoperative radiotherapy in patients with pancreatic cancer and arterial involvement despite a lack of Level 1 evidence on survival benefit. Although it has been suggested that preoperative radiotherapy may increase the risk of postpancreatectomy haemorrhage (PPH) and morbidity, evidence is again lacking. This study investigated the association between preoperative radiotherapy and both PPH and major morbidity following arterial divestment/resection during pancreatic adenocarcinoma resection after chemotherapy. Methods Consecutive patients diagnosed with pancreatic adenocarcinoma and > 180° arterial involvement who were treated with preoperative chemotherapy with or without radiotherapy followed by pancreatic resection with arterial divestment/resection were included in the study. Logistic regression analyses including propensity score-based overlap weighting were performed to investigate associations between radiotherapy and in-hospital PPH grade B/C and major morbidity, expressed as adjusted risk differences (aRDs). Results Overall, 246 patients undergoing pancreatic resection with arterial resection (169, 69%) or divestment (77, 31%) were included. Radiotherapy was not associated with PPH (aRD 6%; 95% confidence interval (c.i.) −3 to 14), regardless of arterial divestment (aRD 3%; 95% c.i. −5 to 11) or arterial resection (aRD 12%; 95% c.i. 1 to 23; Pinteraction = 0.189). Radiotherapy was associated with a 14% (95% c.i. 2 to 25) higher risk of major morbidity, especially after arterial resection (aRD 27%; 95% c.i. 11 to 43) compared with arterial divestment (aRD −12%; 95% c.i. −35 to 11; Pinteraction = 0.006) and after external beam radiotherapy (aRD 21%; 95% c.i. 8 to 32) compared with stereotactic body radiotherapy (aRD −12%; 95% c.i. −27 to 6; Pinteraction = 0.0001). Ninety-day mortality was increased, albeit not significantly, after preoperative radiotherapy (10 (8%) versus 3 (3%) deaths with versus without preoperative radiotherapy, respectively; P = 0.067). Conclusions Radiotherapy before resection of pancreatic cancer with > 180° arterial involvement was associated with an increased risk of postoperative major morbidity when arterial resection, but not arterial divestment, was performed. This risk should be taken into account when considering preoperative radiotherapy in patients who may require arterial resection.

Abstract Background The increased use of superior mesenteric artery (SMA) divestment has been a driver behind the increased resection rate for locally advanced pancreatic cancer following preoperative therapy. This has also resulted in an increase in the rate of postoperative neurogenic diarrhoea, but knowledge about postoperative neurogenic diarrhoea is lacking. The aims of this study were to determine the incidence, risk factors, management, and outcomes of neurogenic diarrhoea after SMA divestment/resection for pancreatic adenocarcinoma. Methods This multicentre retrospective study included consecutive patients undergoing pancreatic adenocarcinoma resection, including SMA divestment/resection, after preoperative chemotherapy with or without radiotherapy between 2016 and 2022. Primary endpoints were the incidence of postoperative neurogenic diarrhoea, associated factors, treatment strategies, and outcomes. Secondary endpoints were the rate of adjuvant chemotherapy and the impact of neurogenic diarrhoea on overall survival (OS). Results Overall, 291 patients who underwent pancreatic resection with concomitant SMA divestment (240, 82%) or resection (51, 18%) were included in the study. Postoperative neurogenic diarrhoea was diagnosed in 193 patients. The adjusted risk of developing neurogenic diarrhoea was 59% (95% confidence interval (c.i.) 46 to 73) after ≤ 180° SMA divestment, 80% (95% c.i. 67 to 93) after > 180° SMA divestment, and 77% (95% c.i. 66 to 88) after SMA resection. Postoperative neurogenic diarrhoea was treated with non-opioid drugs (29, 15%), non-opium opioids (140, 73%), opium tincture (69, 36%), and/or octreotide (49, 25%), and normalized in 51% of patients. After adjusting for confounders, neurogenic diarrhoea was not significantly associated with OS (hazard ratio 0.83; 95% c.i. 0.55 to 1.25). Conclusion Neurogenic diarrhoea occurred in two-thirds of patients following resection of pancreatic adenocarcinoma with concomitant SMA divestment/resection, particularly after > 180° SMA divestment or SMA resection. Although challenging to manage, neurogenic diarrhoea is not associated with impaired OS. Evidence-based treatment strategies are needed for adequate management.

Background: ASCO recommends extended venous thromboembolism (VTE) prophylaxis with low-molecular-weight heparin (LMWH) or direct oral anticoagulants (DOACs) following cancer surgery. However, these recommendations were based on trials using routine venography, which detects asymptomatic VTEs, and real-life efficacy is not well studied. We aimed to assess the association of extended VTE prophylaxis with the incidence of clinically significant VTE after elective cancer surgery. Patients and Methods: In this retrospective, population-based cohort study, we identified patients who underwent surgical resection for lung, breast, esophageal, gastric, pancreas, and colon cancer from 2010 to 2017 using the SEER–Medicare linked dataset. Patients were divided into 1 of 2 main groups for comparative analyses: those who received extended VTE prophylaxis after cancer surgery and those who did not. Patients who received extended VTE prophylaxis after cancer surgery were identified as those prescribed prophylactic doses of LMWH or a DOAC within 7 days of discharge, as captured in Medicare Part D files. Results: A total of 113,739 Medicare beneficiaries were identified, of whom 1,570 (1.4%) received extended VTE prophylaxis. There was a year-over-year increase in the use of extended VTE prophylaxis during the study period, rising from 0.6% in 2010 to 3.3% in 2017. The overall incidence of VTE was 1.6% at 1 month, 4.3% at 6 months, 5.7% at 12 months, with significant differences observed across cancer types ( P <.001). However, patients who received extended VTE prophylaxis had a higher 1-year cumulative incidence of postoperative VTE compared with those who did not (11.4% vs 5.3%; P <.001), an association that was consistent across cancer sites. In adjusted analyses, extended VTE prophylaxis was independently associated with an increased risk of VTE (hazard ratio, 1.6; 95% CI, 1.3–2.0; P <.001). Extended prophylaxis was also associated with a higher 1-year incidence of bleeding events compared with patients who did not receive prophylaxis (12.0% vs 8.5%; P <.001). Conclusions: The utilization of extended VTE prophylaxis after cancer surgery remains low, although it has increased every year. Paradoxically, patients who received extended VTE prophylaxis had higher incidences of clinically significant VTE and bleeding compared with those who did not, likely reflecting patient selection and surveillance bias after surgery. In light of these findings, national guidelines recommending postoperative extended VTE prophylaxis, and its use as a surrogate for quality of care, should continue to be re-examined.

Background: Upfront resectable pancreatic ductal adenocarcinoma (PDAC) is defined by the NCCN as disease with ≤180° portomesenteric vein (PMV) abutment. However, the clinical significance of PMV abutment in this cohort remains unexplored, and we sought to investigate its impact. Methods: This multi-institutional study included patients who underwent pancreatoduodenectomy (PD) for upfront resectable PDAC from 2002 to 2023. Patients with PDAC with ≤180° PMV abutment were compared with those without. Overall survival (OS) was compared and stratified based on whether patients underwent upfront surgery or neoadjuvant therapy (NAT). Results: Among 1,446 patients included, 521 (36.0%) had PMV abutment. Median OS for patients with PMV abutment was 28.8 months compared with 31.2 months for those without ( P =.17). In a stratified analysis of patients who underwent upfront surgery, patients with PMV abutment had worse OS (19.2 vs 27.6 months; P <.05) and lower R0 resection rates (63.1% vs 87.2%; P <.05) compared with those without. However, in patients who underwent NAT, this difference in R0 resection rate was not observed (91.4% vs 94.0%, respectively; P =.27). Furthermore, there was no significant difference in median OS with NAT (42.5 vs 51.6 months, respectively; P =.48). Conclusions: In this largest cohort to date of patients with upfront resectable PDAC, PMV abutment was associated with worse OS compared with no PMV abutment when an upfront resection strategy was used. The use of NAT in patients with PMV abutment mitigated this survival difference with increased R0 resection rates. These findings suggest that patients with upfront resectable PDAC with PMV abutment benefit from a NAT approach for optimal survival outcomes, and that the current criteria guidelines need to be redefined.

BACKGROUND: The Ventral Rectopexy International Expert Panel recently published a consensus update on ventral rectopexy. The ability of large language models to synthesize the literature on ventral rectopexy without an explicit knowledge base was studied before the publication of the consensus. OBJECTIVE: To compare the responses and citations of different large language models on ventral rectopexy using the expert panel consensus as the reference standard. DESIGN: ChatGPT-4o, Gemini 1.5 Pro, and OpenEvidence were compared on content appropriateness (1 = inappropriate to 5 = appropriate), readability (Flesch reading ease), response length, citation fabrication, and citation quality per Oxford Levels of Evidence. The most content-appropriate chatbot response selected by the expert panel was de-identified and presented alongside the consensus text to 15 colorectal surgeons who attempted to identify the chatbot-generated text. SETTINGS: Questions were submitted from September 18 to 19, 2024. Analysis was performed before the online publication of the consensus on January 30, 2025. MAIN OUTCOME MEASURES: The main outcome measures included content appropriateness, fabricated citation rate, citation quality, and the accuracy of identifying human versus chatbot text by colorectal surgeons. RESULTS: OpenEvidence ranked highest for content appropriateness (mean 3.5/5), above Gemini (3.0/5) and ChatGPT (2.8/5; p < 0.001). ChatGPT was most verbose with the highest readability scores ( p = 0.021). ChatGPT fabricated 53% of citations; Gemini fabricated 12%; OpenEvidence fabricated 0% ( p < 0.001). All OpenEvidence citations were peer reviewed, with 40 of 117 (34%) citing level I to III studies compared with 46 of 94 (49%) of the references cited in the consensus ( p = 0.043). Chatbot-generated responses were identified with 28 of 51 (55%) accuracy. LIMITATIONS: Reproducibility may be affected due to the nature of large language models and the availability of the consensus after publication. CONCLUSIONS: OpenEvidence outperformed Gemini 1.5 Pro and ChatGPT-4o in content appropriateness and peer-reviewed citation quantity and quality. Chatbot-generated text was indistinguishable from expert-authored consensus to subject matter experts. Large language models, as an early-stage research tool, may be viable for future consensus working groups, provided transparent disclosure and rigorous oversight. See Video Abstract . ¿PUEDEN LOS MODELOS LINGÜÍSTICOS DE GRAN TAMAÑO SER UNA HERRAMIENTA VIABLE PARA LOS GRUPOS DE TRABAJO DE CONSENSO? LA EXPERIENCIA DEL GRUPO DE CONSENSO DE EXPERTOS EN RECTOPEXIA VENTRAL ANTECEDENTES: El Panel Internacional de Expertos en Rectopexia Ventral publicó recientemente una actualización consensuada sobre la rectopexia ventral. Antes de la publicación del consenso, se estudió la capacidad de los grandes modelos lingüísticos para sintetizar la bibliografía sobre la rectopexia ventral sin una base de conocimientos explícita. Objetivo: Comparar las respuestas y citas de diferentes grandes modelos lingüísticos sobre la rectopexia ventral utilizando el consenso del panel de expertos como estándar de referencia. DISEÑO: Se compararon ChatGPT-4o, Gemini 1.5 Pro y OpenEvidence en cuanto a la idoneidad del contenido (1 = inadecuado a 5 = adecuado), la legibilidad (índice de legibilidad de Flesch), la longitud de la respuesta, la fabricación de citas y la calidad de las citas según los niveles de evidencia de Oxford. La respuesta del chatbot más adecuada en cuanto al contenido seleccionada por el panel de expertos se anonimizó y se presentó junto con el texto del consenso a 15 cirujanos colorrectales que intentaron identificar el texto generado por el chatbot. ENTORNO: Las preguntas se enviaron los días 18 y 19 de septiembre de 2024. El análisis se realizó antes de la publicación del consenso en línea el 30 de enero de 2025. PRINCIPALES MEDIDAS DE RESULTADOS: Adecuación del contenido, tasa de citas inventadas, calidad de las citas, precisión en la identificación del texto humano frente al del chatbot por parte de los cirujanos colorrectales. RESULTADOS: OpenEvidence obtuvo la puntuación más alta en cuanto a la adecuación del contenido (media de 3,5/5), por encima de Gemini (3,0/5) y ChatGPT (2,8/5) (p<0,001). ChatGPT fue el más prolijo, con las puntuaciones más altas en legibilidad (p = 0,021). ChatGPT inventó el 53% de las citas; Gemini inventó el 12 %; OpenEvidence inventó el 0 % (p < 0,001). Todas las citas de OpenEvidence fueron revisadas por pares, con 40/117 (34 %) que citaban estudios de nivel I-III frente a 46/94 (49 %) de las referencias citadas en el consenso (p = 0,043). Las respuestas generadas por el chatbot se identificaron con una precisión del 28/51 (55 %). LIMITACIONES: Reproducibilidad debido a la naturaleza de los modelos de lenguaje grandes y a la disponibilidad del consenso tras la publicación. CONCLUSIONES: OpenEvidence superó a Gemini 1.5 Pro y ChatGPT-4o en cuanto a la idoneidad del contenido y la cantidad y calidad de las citas revisadas por pares. El texto generado por el chatbot era indistinguible del consenso redactado por expertos para los expertos en la materia. Los modelos de lenguaje grandes como herramienta de investigación en fase inicial pueden ser viables para futuros grupos de trabajo de consenso, siempre que se garantice una divulgación transparente y una supervisión rigurosa. ( AI-generated translation )

BACKGROUND: The first total pancreatectomy (TP) resulting in survival past the immediate postoperative period was performed at Mayo Clinic in 1944. Although still uncommonly performed, indications have recently fluctuated. We aimed to evaluate trends in TP use and outcomes over four decades. STUDY DESIGN: Patients who underwent single-stage TP at Mayo Clinic Rochester from 1988 to 2024 were analyzed in two cohorts: early era (EE, 1988 to 2009) and modern era (ME, 2010 to 2024). RESULTS: In total, 437 patients were identified: 118 during EE (mean 8 per year) and 319 during ME (mean 21 per year). Primary indications were adenocarcinoma (42% EE vs 60% ME), intraductal papillary mucinous neoplasm (31% EE vs 17% ME), and chronic pancreatitis (11% EE vs 13% ME; p < 0.001). Concurrent vascular resection was performed in 9.3% (EE; all venous only) vs 53% (ME; venous alone in 20% and arterial with or without venous in 33%; p < 0.001). Multivisceral resection was performed in <1% (EE) vs 24% (ME; p < 0.001). Major complications occurred in 13% (EE) vs 27% (ME; p = 0.018), and 90-day mortality was 3.4% (EE) vs 6.3% (ME; p = 0.35). For adenocarcinoma, 5-year median overall survival from both surgery and diagnosis was significantly improved in ME (p = 0.009 and p < 0.001, respectively). Median last HbA1c was 7.7 (EE) vs 7.3 (ME; p < 0.001). Among patients surviving more than 1 year, insulin pumps were used in 12% (EE) vs 49% (ME; p < 0.001). Conclusions: The use of TP has dramatically increased in recent years, primarily for adenocarcinoma alongside increased use of neoadjuvant therapy and ever-expanding criteria for anatomic resectability. Operative complexity has significantly increased with resultant increased perioperative morbidity. TP remains a higher-risk procedure, specifically with en bloc vascular resections, emphasizing the importance of appropriate patient selection, preoperative patient education, and thoughtful postoperative and long-term management.

Abstract Importance and Objective Pancreatic cancer can lead to severe stenosis of the portomesenteric venous (PV/SMV) confluence due to extrinsic compression or direct invasion. This can result in venous hypertension associated with post-prandial abdominal pain, gastrointestinal bleeding, and ascites. In patients with unresectable tumors, transhepatic PV/SMV stenting has been reported; however, its safety and efficacy are poorly understood. Design, Setting and Participants All unresectable pancreatic cancer patients referred to Interventional Radiology to undergo palliative transhepatic PV/SMV stenting (2011–2024) were collected. Patient demographics, CT scans, transhepatic venograms, and clinical outcomes were reviewed. Intervention, Main Outcomes and Results In total, 129 patients were included; 92% had pancreatic ductal adenocarcinoma. Tumors were unresectable due to unreconstructable vascular involvement, metastatic disease, or poor performance status. Nearly 81% were symptomatic, while the remaining 24 asymptomatic patients presented with significant venous hypertensive varices and collaterals on imaging. Complete venous occlusion was seen in 39% of patients at the PV, the SMV, or the PV/SMV confluence; 97% of procedures were successful, with 4 technical failures at obtaining distal venous wire access. Adverse events occurred in 4 patients. Radiological follow-up was available in 94% of patients. Post-procedural primary stent patency was 80% at a median follow-up time of 20 months. Follow-up was available in 102 of the 105 symptomatic patients, with 85% reporting an improvement in symptoms. Conclusions and Relevance Palliative transhepatic PV/SMV stenting is a technically feasible and safe procedure in well-selected patients. Symptoms improvement can be seen in most patients. High-volume centers should consider this technique for patients with unresectable tumors who present with symptomatic stenosis or short segment occlusion.

ImportanceIdentification of factors associated with variation in outpatient surgery may further quality improvement efforts to safely reduce postoperative hospital length of stay nationally.ObjectivesTo explore variation in the use of outpatient surgery, incorporating patient, geographic, and hospital factors.Design, Setting, and ParticipantsThis retrospective cross-sectional study used deidentified administrative claims data from OptumLabs Data Warehouse. Participants included adults who underwent 1 of 10 general, urological, or gynecological operations between January 1, 2015, and June 30, 2021, in the US. Patients who underwent combined procedures or reoperations or had at least 15 Elixhauser comorbidities were excluded. Data were analyzed from July 26 to December 16, 2023.ExposureInpatient or outpatient surgical procedures.Main Outcomes and MeasuresMultilevel logistic regression assessed variation in the use of outpatient surgery rates by hospital characteristics (bed size, presence of trainees, and rural referral center status) and hospital census division, adjusting for patient factors (age, sex, number of Elixhauser comorbidities, year, and rural-urban commuting area). This multilevel model allowed for the sources of variability to be quantitatively attributed to patient characteristics, geography, and hospital characteristics.ResultsA total of 330 424 (72.3%) of 456 954 included patients underwent outpatient surgery. The median age was 54 (IQR, 41-67) years, and of those with data available, most patients were female (268 692 of 414 193 [64.9%]). The likelihood of outpatient surgery varied significantly by hospital census division for all 10 operations (eg, MIS salpingo-oophorectomy range, 29.6%-58.8%; P &amp;lt; .001). Variation in hospital census division contributed most to outpatient surgery for 8 of 10 operations compared with other patient and hospital characteristics. Hospital census division contributed the greatest degree to the variation in outpatient simple mastectomy (20.6%) and the least to outpatient open ventral hernia repair (0.7%). Multivariable analysis showed that the odds of outpatient surgery for patients from metropolitan areas were higher for minimally invasive salpingo-oophorectomy (odds ratio [OR], 1.62; 95% CI, 1.34-1.95) and open ventral hernia repair (OR, 1.16; 95% CI, 1.09-1.24). Hospitals with 400 or more beds were independently associated with decreased odds of outpatient surgery compared with hospitals with 50 to 199 beds for 4 of 7 operations (MIS paraesophageal hernia repair [OR, 0.58; 95% CI, 0.47-0.71; P &amp;lt; .001]; MIS cholecystectomy [OR, 0.73; 95% CI, 0.68-0.78; P &amp;lt; .001]; open ventral hernia [OR, 0.51; 95% CI, 0.46-0.57; P &amp;lt; .001]; MIS ventral hernia repair [OR, 0.66; 95% CI, 0.56-0.77; P &amp;lt; .001]). The presence of a residency training program was independently associated with increased odds of outpatient surgery for simple mastectomy (OR, 1.35; 95% CI, 1.16-1.58; P &amp;lt; .001) and mastectomy with reconstruction (OR, 1.50; 95% CI, 1.27-1.77; P &amp;lt; .001) and decreased odds of outpatient surgery for minimally invasive cholecystectomy (OR, 0.96; 95% CI, 0.92-1.00; P = .04), open ventral hernia repair (OR, 0.93; 95% CI, 0.86-1.00; P = .04), and total thyroidectomy (OR, 0.84; 95% CI, 0.71-1.00; P = .04).Conclusions and RelevanceIn this cross-sectional study, significant variation existed in the use of outpatient surgery in the US and appeared to be driven primarily by hospital geography. Addressing these variations may improve the use of resources.