Race and Odds of Surgery Offer in Small Bowel and Pancreas Neuroendocrine Neoplasms.

BACKGROUND: Despite existing society guidelines, management of pancreatic (PanNEN) and small bowel (SBNEN) neuroendocrine neoplasms remains inconsistent. The purpose of this study was to identify patient- and/or disease-specific characteristics associated with increased odds of being offered surgery for PanNEN and SBNEN. PATIENTS AND METHODS: The Surveillance, Epidemiology, and End Results (SEER) Program database and the National Cancer Database (NCDB) were queried for patients with PanNEN/SBNEN. Demographic and pathologic data were compared between patients who were offered surgery and those who were not. Multivariate logistic regression was performed to identify factors independently associated with being offered surgery. RESULTS: In SEER, there were 3641 patients with PanNEN (54.7% were offered surgery) and 5720 with SBNEN (86.0% were offered surgery). On multivariate analysis of SEER, non-white race was associated with decreased odds of surgery offer for SBNEN [odds ratio (OR) 0.58, p < 0.001], but not PanNEN (p = 0.187). In NCDB, there were 28,483 patients with PanNEN (57.5% were offered surgery) and 42,675 with SBNEN (86.9% were offered surgery). On multivariate analysis of NCDB, non-white race was also associated with decreased odds of surgery offer for SBNEN (OR 0.61, p < 0.001) but not PanNEN (p = 0.414). CONCLUSIONS: This study's findings suggest that, in addition to previously reported disparities in surgical resection and surgery refusal rates, racial/ethnic disparities also exist earlier in the course of treatment, with non-white patients being less likely to be offered surgery for SBNEN but not for PanNEN; this is potentially due to discrepancies in rates of referral to academic centers for pancreas and small bowel malignancies.

Area deprivation and rurality impact overall survival and adjuvant therapy administration in patients with pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND: The impact of neighborhood deprivation on outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) is not well-described and represents an area to improve disparities. METHODS: We retrospectively queried our prospectively maintained database of patients with PDAC (2014-2022). Patients were grouped by Area Deprivation Index (ADI) and rural-urban commuting area (RUCA) codes. Cox proportional hazards models and logistic regressions were used to investigate effect on overall survival (OS) and adjuvant therapy administration. RESULTS: 536 patients were included. High ADI patients (more disadvantaged, n = 184) were more likely to identify as non-Hispanic Black (17.9% vs. 4.8%, p < 0.01) and were more likely to be from rural areas (49.5% vs. 18.5%, p < 0.01). High ADI was independently associated with decreased OS (HR (95% CI): 1.31 (1.01-1.69), p = 0.04). Urban high ADI patients were 3.5 times more likely to receive adjuvant therapy than rural high ADI patients (OR [95% CI]: 3.48 [1.26-9.61], p = 0.02). CONCLUSION: Patients from the most disadvantaged neighborhoods have decreased OS. Access to adjuvant therapy likely contributes to this disparity in rural areas. Investigation into sources of this OS disparity and identification of barriers to adjuvant therapy will be crucial to improve outcomes in underserved patients with PDAC.

Impact of Prehabilitation on Postoperative Mortality and the Need for Non-Home Discharge in High-Risk Surgical Patients.

BACKGROUND: The preoperative period is an important target for interventions (eg Surgical Prehabilitation and Readiness [SPAR]) that can improve postoperative outcomes for older patients with comorbidities. STUDY DESIGN: To determine whether a preoperative multidisciplinary prehabilitation program (SPAR) reduces postoperative 30-day mortality and the need for non-home discharge in high-risk surgical patients, surgical patients enrolled in a prehabilitation program targeting physical activity, pulmonary function, nutrition, and mindfulness were compared with historical control patients from 1 institution's American College of Surgeons (ACS) NSQIP database. SPAR patients were propensity score-matched 1:3 to pre-SPAR NSQIP patients, and their outcomes were compared. The ACS NSQIP Surgical Risk Calculator was used to compare observed-to-expected ratios for postoperative outcomes. RESULTS: A total of 246 patients were enrolled in SPAR. A 6-month compliance audit revealed that overall patient adherence to the SPAR program was 89%. At the time of analysis, 118 SPAR patients underwent surgery with 30 days of follow-up. Compared with pre-SPAR NSQIP patients (n = 4,028), SPAR patients were significantly older with worse functional status and more comorbidities. Compared with propensity score-matched pre-SPAR NSQIP patients, SPAR patients had significantly decreased 30-day mortality (0% vs 4.1%, p = 0.036) and decreased need for discharge to postacute care facilities (6.5% vs 15.9%, p = 0.014). Similarly, SPAR patients exhibited decreased observed 30-day mortality (observed-to-expected ratio 0.41) and need for discharge to a facility (observed-to-expected ratio 0.56) compared with their expected outcomes using the ACS NSQIP Surgical Risk Calculator. CONCLUSIONS: The SPAR program is safe and feasible and may reduce postoperative mortality and the need for discharge to postacute care facilities in high-risk surgical patients.

Piperacillin-Tazobactam Compared With Cefoxitin as Antimicrobial Prophylaxis for Pancreatoduodenectomy: A Randomized Clinical Trial.

Importance: Despite improvements in perioperative mortality, the incidence of postoperative surgical site infection (SSI) remains high after pancreatoduodenectomy. The effect of broad-spectrum antimicrobial surgical prophylaxis in reducing SSI is poorly understood. Objective: To define the effect of broad-spectrum perioperative antimicrobial prophylaxis on postoperative SSI incidence compared with standard care antibiotics. Design, Setting, and Participants: Pragmatic, open-label, multicenter, randomized phase 3 clinical trial at 26 hospitals across the US and Canada. Participants were enrolled between November 2017 and August 2021, with follow-up through December 2021. Adults undergoing open pancreatoduodenectomy for any indication were eligible. Individuals were excluded if they had allergies to study medications, active infections, chronic steroid use, significant kidney dysfunction, or were pregnant or breastfeeding. Participants were block randomized in a 1:1 ratio and stratified by the presence of a preoperative biliary stent. Participants, investigators, and statisticians analyzing trial data were unblinded to treatment assignment. Intervention: The intervention group received piperacillin-tazobactam (3.375 or 4 g intravenously) as perioperative antimicrobial prophylaxis, while the control group received cefoxitin (2 g intravenously; standard care). Main Outcomes and Measures: The primary outcome was development of postoperative SSI within 30 days. Secondary end points included 30-day mortality, development of clinically relevant postoperative pancreatic fistula, and sepsis. All data were collected as part of the American College of Surgeons National Surgical Quality Improvement Program. Results: The trial was terminated at an interim analysis on the basis of a predefined stopping rule. Of 778 participants (378 in the piperacillin-tazobactam group [median age, 66.8 y; 233 {61.6%} men] and 400 in the cefoxitin group [median age, 68.0 y; 223 {55.8%} men]), the percentage with SSI at 30 days was lower in the perioperative piperacillin-tazobactam vs cefoxitin group (19.8% vs 32.8%; absolute difference, -13.0% [95% CI, -19.1% to -6.9%]; P < .001). Participants treated with piperacillin-tazobactam, vs cefoxitin, had lower rates of postoperative sepsis (4.2% vs 7.5%; difference, -3.3% [95% CI, -6.6% to 0.0%]; P = .02) and clinically relevant postoperative pancreatic fistula (12.7% vs 19.0%; difference, -6.3% [95% CI, -11.4% to -1.2%]; P = .03). Mortality rates at 30 days were 1.3% (5/378) among participants treated with piperacillin-tazobactam and 2.5% (10/400) among those receiving cefoxitin (difference, -1.2% [95% CI, -3.1% to 0.7%]; P = .32). Conclusions and Relevance: In participants undergoing open pancreatoduodenectomy, use of piperacillin-tazobactam as perioperative prophylaxis reduced postoperative SSI, pancreatic fistula, and multiple downstream sequelae of SSI. The findings support the use of piperacillin-tazobactam as standard care for open pancreatoduodenectomy. Trial Registration: ClinicalTrials.gov Identifier: NCT03269994.

Postoperative Proton Pump Inhibitors are associated with a significantly higher rate of delayed gastric emptying after pancreatoduodenectomy.

BACKGROUND: Proton pump inhibitors (PPIs) are effective in reducing marginal ulcers after pancreatoduodenectomy. However, their impact on perioperative complications has not been defined. METHODS: We retrospectively analyzed the effect of postoperative PPIs on 90-day perioperative outcomes in all patients who underwent pancreatoduodenectomy at our institution from April 2017 to December 2020. RESULTS: 284 patients were included; 206 (72.5%) received perioperative PPIs, 78 (27.5%) did not. The two cohorts were similar in demographics and operative variables. Postoperatively, the PPI cohort had significantly higher rates of overall complications (74.3% vs. 53.8%) and delayed gastric emptying (28.6% vs. 11.5%), p < 0.05. However, no differences in infectious complications, postoperative pancreatic fistula, or anastomotic leaks were seen. On multivariate analysis, PPI was independently associated with a higher risk of overall complications (OR 2.46, CI 1.33-4.54) and delayed gastric emptying (OR 2.73, CI 1.26-5.91), p = 0.011. Four patients developed marginal ulcers within 90-days postoperatively; all were in the group who received PPIs. CONCLUSION: Postoperative proton pump inhibitor use was associated with a significantly higher rate of overall complications and delayed gastric emptying after pancreatoduodenectomy.

Video Interviews and Surgical Applicants' Ability to Assess Fit to Residency Programs.

INTRODUCTION: Due to the COVID-19 pandemic, the recruitment cycle for the 2021 Match was performed virtually. This Association for Surgical Education (ASE)-sponsored survey set out to study applicants' ability to assess the factors contributing to fit through video interviews. METHODS: An IRB-approved, online, anonymous survey was distributed to surgical applicants at a single academic institution and through the ASE clerkship director distribution list between the rank order list certification deadline and Match Day. Applicants used 5-point Likert-type scales to rate factors for importance to fit and their ease of assessment through video interviewing. A variety of recruitment activities were also rated by applicants for their perceived helpfulness in assessment of fit. RESULTS: One hundred and eighty-three applicants responded to the survey. The three most important factors for applicant fit were how much the program cared, how satisfied residents seem with their program, and how well residents get along. Resident rapport, diversity of the patient population, and quality of the facilities were hardest to assess through video interviews. In general, diversity-related factors were more important to female and non-White applicants, but not more difficult to assess. Interview day and resident-only virtual panels were the most helpful recruitment activities, while virtual campus tours, faculty-only panels, and a program's social media were the least helpful. CONCLUSIONS: This study provides valuable insight into the limitations of virtual recruitment for surgical applicants' perception of fit. These findings and the recommendations herein should be taken into consideration by residency program leadership to ensure successful recruitment of diverse residency classes.

4,300 steps per day prior to surgery are associated with improved outcomes after pancreatectomy.

BACKGROUND: Decreased preoperative physical fitness and low physical activity have been associated with preoperative functional reserve and surgical complications. We sought to evaluate daily step count as a measure of physical activity and its relationship with post-pancreatectomy outcomes. METHODS: Patients undergoing pancreatectomy were given a remote telemonitoring device to measure their preoperative levels of physical activity. Patient activity, demographics, and perioperative outcomes were collected and compared in univariate and multivariate logistic regression analysis. RESULTS: 73 patients were included. 45 (61.6%) patients developed complications, with 17 (23.3%) of those patients developing severe complications. These patients walked 3437.8 (SD 1976.7) average daily steps, compared to 5918.8 (SD 2851.1) in patients without severe complications (p < 0.001). In logistic regression analysis, patients who walked less than 4274.5 steps had significantly higher odds of severe complications (OR = 7.5 (CI 2.1, 26.8), p = 0.002). CONCLUSION: Average daily steps below 4274.5 before surgery are associated with severe complications after pancreatectomy. Preoperative physical activity levels may represent a modifiable target for prehabilitation protocols.

Increased Morbidity and Mortality After Hepatectomy for Colorectal Liver Metastases in Frail Patients is Largely Driven by Worse Outcomes After Minor Hepatectomy: It's Not "Just a Wedge".

BACKGROUND: Frailty is associated with postoperative mortality, but its significance after hepatectomy for colorectal liver metastases (CRLM) is poorly defined. This study evaluated the impact of frailty after hepatectomy for CRLM. METHODS: The study identified 8477 patients in National Surgical Quality Improvement Program databases from 2014 to 2019 and stratified them by frailty score using the risk analysis index as very frail (>90th percentile), frail (75th-90th percentile), or non-frail (< 75th percentile). Multivariate regression models determined the impact of frailty on perioperative outcomes, including by the extent of hepatectomy. RESULTS: The procedures performed were 2752 major hepatectomies (left hepatectomy, right hepatectomy, trisectionectomy) and 5725 minor hepatectomies (≤2 segments) for 870 (10.3%) very frail, 1680 (19.8%) frail, and 5927 (69.9%) non-frail patients. Postoperatively, the very frail and frail patients experienced more complications (very frail [41.8%], frail [35.1%], non-frail [31.0%]), which resulted in a longer hospital stay (very-frail [5.7 days], frail [5.8 days], non-frail [5.1 days]), a higher 30-day mortality (very-frail [2.2%], frail [1.3%], non-frail [0.5%]), and more discharges to a facility (very frail [6.8%], frail [3.7%], non-frail [2.6%]) (p < 0.05) although they underwent similarly extensive (major vs. minor) hepatectomies. In the multivariate analysis, frailty was independently associated with complications (very-frail [odds ratio {OR}, 1.70], frail [OR, 1.25]) and 30-day mortality (very-frail [OR, 4.24], frail [OR, 2.41]) (p < 0.05). After minor hepatectomy, the very frail and frail patients had significantly higher rates of complications and 30-day mortality than the non-frail patients, and in the multivariate analysis, frailty was independently associated with complications (very frail [OR, 1.97], frail [OR, 1.27]) and 30-day mortality (very frail [OR, 6.76], frail [OR, 3.47]) (p < 0.05) after minor hepatectomy. CONCLUSIONS: Frailty predicted significantly poorer outcomes after hepatectomy for CRLM, even after only a minor hepatectomy.

Cause and outcome of aborting a difficult laparoscopic cholecystectomy due to severe inflammation: a study of operative notes.

BACKGROUND: Upon encountering a difficult cholecystectomy in which, after a reasonable trial of dissection, anatomical identification has not been attained due to severe inflammation, and the risk of additional dissection is deemed to be hazardous, "bail-out" strategies are encouraged safety valves. One strategy is to abort the cholecystectomy and refer the patient to a HPB center for further management. METHODS: A retrospective review was conducted of cholecystectomies performed by HPB surgeons at our center between 2005 and 2019. We identified 63 patients who had an aborted cholecystectomy because of acute or chronic cholecystitis and were referred for additional care. Of these, operative notes and other clinical records were available for 43 patients who were included in this study. RESULTS: 42 cholecystectomies (98%) were started laparoscopically. 25 patients (58%) had chronic cholecystitis, and 18 (42%) had acute cholecystitis. 40 cases (93%) fell into the highest level of difficulty on the Nassar scale (Grade 4). Procedures were aborted at the following stages of dissection: in 10 patients (23%), none of the gallbladder was identified; in another 11 (26%), only the dome of gallbladder was identified; the body of the gallbladder was exposed in 13 (30%); and dissection of the hepatocystic triangle was attempted unsuccessfully in 9 (21%). Following referral to our center, 30 patients (70%) were managed with total cholecystectomy while in 13 cases (30%), subtotal cholecystectomy was performed. CONCLUSION: Aborting cholecystectomy and referring the patient to an HPB center is rarely needed but is an effective bail-out strategy for general surgeons encountering highly difficult operative conditions due to inflammation.

Applicants' perception of fit to residency programmes in the video-interview era: A large multidisciplinary survey.

INTRODUCTION: 'Fit' refers to an applicants' perceived compatibility to a residency programme. A variety of structural, identity-related and relational factors contribute to self-assessments of fit. The 2021 residency recruitment cycle in the USA was performed virtually due to the COVID-19 pandemic. Little is known about how video-interviewing may affect residency applicants' ability to gauge fit. METHODS: A multidisciplinary, anonymous survey was distributed to applicants at a large academic institution between rank order list (ROL) certification deadline and Match Day 2021. Using Likert-type scales, applicants rated factors for importance to 'fit' and their ease of assessment through video-interviewing. Applicants also self-assigned fit scores to the top-ranked programme in their ROL using Likert-type scales with pairs of anchoring statements. RESULTS: Four hundred seventy-three applicants responded to the survey (25.7% response rate). The three most important factors to applicants for assessment of fit (how much the programme seemed to care, how satisfied residents seem with their programme and how well the residents get along) were also the factors with the greatest discrepancy between importance and ease of assessment through video-interviewing. Diversity-related factors were more important to female applicants compared with males and to non-White applicants compared with White applicants. Furthermore, White male applicants self-assigned higher fit scores compared with other demographic groups. CONCLUSION: There is a marked discrepancy between the most important factors to applicants for fit and their ability to assess those factors virtually. Minoritised trainees self-assigned lower fit scores to their top-ranked programme, which should raise concern amongst medical educators and highlights the importance of expanding current diversity, equity and inclusion efforts in academic medicine.

Improved outcomes with minimally invasive pancreaticoduodenectomy in patients with dilated pancreatic ducts: a prospective study.

BACKGROUND: Little is known about what factors predict better outcomes for patients who undergo minimally invasive pancreaticoduodenectomy (MIPD) versus open pancreaticoduodenectomy (OPD). We hypothesized that patients with dilated pancreatic ducts have improved postoperative outcomes with MIPD compared to OPD. METHODS: All patients undergoing pancreaticoduodenectomy were prospectively followed over a time period of 47 months, and perioperative and pathologic covariates and outcomes were compared. Ideal outcome after PD was defined as follows: (1) no complications, (2) postoperative length of stay < 7 days, and (3) negative (R0) margins on pathology. Patients with dilated pancreatic ducts (≥ 3 mm) who underwent MIPD were 1:3 propensity score-matched to patients with dilated ducts who underwent OPD and outcomes compared. Likewise, patients with non-dilated pancreatic ducts (< 3 mm) who underwent MIPD were 1:3 propensity score-matched to patients with non-dilated ducts who underwent OPD and outcomes were compared. RESULTS: 371 patients underwent PD-74 (19.9%) MIPD and 297 (80.1%) underwent OPD. Overall, patients who underwent MIPD had significantly less intraoperative blood loss. After 1:3 propensity score matching, patients with dilated pancreatic ducts who underwent MIPD (n = 45) had significantly lower overall complication and 90-day readmission rates compared to matched OPD patients (n = 135) with dilated ducts. Patients with dilated duct who underwent MIPD were more likely to have an ideal outcome than patients with OPD (29 vs 15%, p = 0.035). There were no significant differences in postoperative outcomes among propensity score-matched patients with non-dilated pancreatic ducts who underwent MIPD (n = 29) compared to matched patients undergoing OPD (n = 87) with non-dilated ducts. CONCLUSIONS: MIPD is safe with comparable perioperative outcomes to OPD. Patients with pancreatic ducts ≥ 3 mm appear to derive the most benefit from MIPD in terms of fewer complications, lower readmission rates, and higher likelihood of ideal outcome.

Enhanced recovery pathway after open pancreaticoduodenectomy reduces postoperative length of hospital stay without reducing composite length of stay.

BACKGROUND/PURPOSE: There is no data regarding the impact of enhanced recovery pathways (ERP) on composite length of stay (CLOS) after procedures with increased risk of morbidity and mortality, such as pancreaticoduodenectomy. METHODS: Patients undergoing open pancreaticoduodenectomy before and after implementation of ERP were prospectively followed for 90 days after surgery and complications were severity graded using the Modified Accordion Grading System. A retrospective analysis of patient outcomes were compared before and after instituting ERP. 1:1 propensity score matching was used to compare ERP patient outcomes to those of matched pre-ERP patients. CLOS is defined as postoperative length of hospital stay (PLOS) plus readmission length of hospital stay within 90 days after surgery. RESULTS: 494 patients underwent open pancreaticoduodenectomy - 359 pre-ERP and 135 ERP. In a 1:1 propensity-score-matched analysis of 110 matched pairs, ERP patients had significantly decreased superficial surgical site infections (5.5% vs 15.5% p = 0.015) and significantly increased rates of urinary retention (29.1% vs 7.3% p < 0.0001) compared to matched pre-ERP patients. However, overall complication rate and 90-day readmission rate were not significantly different between matched groups. Propensity score-matched ERP patients had significantly decreased PLOS (7 days vs 8 days p = 0.046) compared to matched pre-ERP patients, but CLOS was not significantly different (9 days vs 9.5 days p = 0.615). CONCLUSION: ERP may reduce PLOS but might not impact the total postoperative time spent in the hospital (i.e. CLOS) within 90 days after pancreaticoduodenectomy.

Inability to manage non-severe complications on an outpatient basis increases non-white patient readmission rates after pancreaticoduodenectomy: A large metropolitan tertiary care center experience.

BACKGROUND: Pancreaticoduodenectomy (PD) has a high rate of readmission, and racial disparities in care could be an important contributor. METHODS: Patients undergoing PD were prospectively followed, and their complications graded using the Modified Accordion Grading System (MAGS). Patient factors and perioperative outcomes for patients with and without postoperative readmission were compared in univariate and multivariate analysis by severity. RESULTS: 837 patients underwent PD, the overall 90-day readmission rate was 27.5%. Non-white race was independently associated with readmission (OR 1.83, p = 0.007). 51.3% of readmissions were for non-severe complications (MAGS <3). Non-white race was independently associated with MAGS non-severe readmission (OR 2.13, p = 0.006), but not MAGS severe readmission. CONCLUSIONS: Non-white patients are more likely to be readmitted, particularly for non-severe complications. Follow up protocols should be tailored to address race disparities in the rates of readmission as readmission for less severe complications could potentially be avoidable.

Care Fragmentation and Mortality in Readmission after Surgery for Hepatopancreatobiliary and Gastric Cancer: A Patient-Level and Hospital-Level Analysis of the Healthcare Cost and Utilization Project Administrative Database.

BACKGROUND: Hepatopancreatobiliary (HPB) and gastric oncologic operations are frequently performed at referral centers. Postoperatively, many patients experience care fragmentation, including readmission to "outside hospitals" (OSH), which is associated with increased mortality. Little is known about patient-level and hospital-level variables associated with this mortality difference. STUDY DESIGN: Patients undergoing HPB or gastric oncologic surgery were identified from select states within the Healthcare Cost and Utilization Project database (2006-2014). Follow-up was 90 days after discharge. Analyses used Kruskal-Wallis test, Youden index, and multilevel modeling at the hospital level. RESULTS: There were 7,536 patients readmitted within 90 days of HPB or gastric oncologic surgery to 636 hospitals; 28% of readmissions (n = 2,123) were to an OSH, where 90-day readmission mortality was significantly higher: 8.0% vs 5.4% (p < 0.01). Patients readmitted to an OSH lived farther from the index surgical hospital (median 24 miles vs 10 miles; p < 0.01) and were readmitted later (median 25 days after discharge vs 12; p < 0.01). These variables were not associated with readmission mortality. Surgical complications managed at an OSH were associated with greater readmission mortality: 8.4% vs 5.7% (p < 0.01). Hospitals with <100 annual HPB and gastric operations for benign or malignant indications had higher readmission mortality (6.4% vs 4.7%, p = 0.01), although this was not significant after risk-adjustment (p = 0.226). CONCLUSIONS: For readmissions after HPB and gastric oncologic surgery, travel distance and timing are major determinants of care fragmentation. However, these variables are not associated with mortality, nor is annual hospital surgical volume after risk-adjustment. This information could be used to determine safe sites of care for readmissions after HPB and gastric surgery. Further analysis is needed to explore the relationship between complications, the site of care, and readmission mortality.

In silico epitope prediction analyses highlight the potential for distracting antigen immunodominance with allogeneic cancer vaccines.

Allogeneic cancer vaccines are designed to induce antitumor immune responses with the goal of impacting tumor growth. Typical allogeneic cancer vaccines are produced by expansion of established cancer cell lines, transfection with vectors encoding immunostimulatory cytokines, and lethal irradiation. More than 100 clinical trials have investigated the clinical benefit of allogeneic cancer vaccines in various cancer types. Results show limited therapeutic benefit in clinical trials and currently there are no FDA approved allogeneic cancer vaccines. We used recently developed bioinformatics tools including the pVAC-seq suite of software tools to analyze DNA/RNA sequencing data from the TCGA to examine the repertoire of antigens presented by a typical allogeneic cancer vaccine, and to simulate allogeneic cancer vaccine clinical trials. Specifically, for each simulated clinical trial we modeled the repertoire of antigens presented by allogeneic cancer vaccines consisting of three hypothetical cancer cell lines to 30 patients with the same cancer type. Simulations were repeated ten times for each cancer type. Each tumor sample in the vaccine and the vaccine recipient was subjected to HLA typing, differential expression analyses for tumor associated antigens (TAAs), germline variant calling, and neoantigen prediction. These analyses provided a robust, quantitative comparison between potentially beneficial TAAs and neoantigens versus distracting antigens present in the allogeneic cancer vaccines. We observe that distracting antigens greatly outnumber shared TAAs and neoantigens, providing one potential explanation for the lack of observed responses to allogeneic cancer vaccines. This analysis provides additional rationale for the redirection of efforts towards a personalized cancer vaccine approach.

Re-defining a high volume center for pancreaticoduodenectomy.

BACKGROUND: The purpose of this study was to re-evaluate the previously utilized definitions of high volume center for pancreaticoduodenectomy to determine/establish an objective, evidence based threshold of hospital volume associated with improvement in perioperative mortality. METHODS: Patients who underwent pancreaticoduodenectomy were identified using the National Cancer Database from 2004 to 2015. The relationship between hospital volume and 90-day mortality was assessed using a logistic regression model. Receiver Operator Characteristic analysis was performed and Youden's statistic was utilized to calculate the optimal cut offs. RESULTS: 42,402 patients underwent elective Pancreaticoduodenectomy at 1238 unique hospitals. A logistic regression was performed which showed a significant inverse linear association between institutional volume and overall 90 day mortality. The maximum improvement in 90 day mortality is seen if the average annual hospital volume was greater than 9 (OR = 0.647 (0.595-0.702), p < 0.0001). When analysis is limited to hospitals that performed >9 cases per year, the maximum improvement in 90 day mortality was noticed at 36 cases per year (OR = 0.458 (0.399-0.525), p < 0.0001). CONCLUSIONS: Based on our results, we recommend defining low, medium, and high volume centers for pancreaticoduodenectomy as hospitals with average annual volume less than 9, 9 to 35, and more than 35 cases per year, respectively.

Feasibility and safety of non-operative management of portal vein aneurysms: a thirty-five year experience.

BACKGROUND: Portal vein aneurysms (PVAs) are rare, though clinically challenging with post-operative mortality approaching 20% and no evidence-based treatment guidelines. We aim to describe our experience with PVAs and recommend optimum management strategies. METHODS: Demographics and clinical details of patients with PVAs admitted to our institution from 1984 to 2019 were reviewed. Clinical presentation, management and outcomes were analysed. RESULTS: PVAs were identified in 18 patients (median age 56 years, range 20-101 years; 13 female); 10 were incidental and 8 diagnosed during abdominal pain work-up. Median aneurysm diameter at diagnosis was 3.4 cm (1.8-5.5 cm), remaining unchanged at 3.5 cm (1.9-4.8 cm) during a 3.2-year follow-up (4 months-31 years). Aneurysm sites were the main portal vein (n = 12), porto-splenic-junction (n = 3), splenic-SMV-junction (n = 2) and right portal vein (n = 1). Thrombosis occurred in 4 patients; 3 developed clinically insignificant cavernous transformation. Two patients underwent surgery for abdominal pain. Postoperatively, one developed PV thrombosis and PVA recurrence occurred in the second. No aneurysm ruptures or mortalities occurred during follow-up. CONCLUSION: PVAs follow a clinically indolent course with structural stability and minimal complications over time. Non-operative management is feasible for most patients. Abdominal pain, large size or thrombosis don't appear to confer additional risks and should not, in isolation, merit surgical intervention.

Less is more in the difficult gallbladder: recent evolution of subtotal cholecystectomy in a single HPB unit.

INTRODUCTION: Subtotal cholecystectomy (SC) is a technique to manage the difficult gallbladder and avoid hazardous dissection and biliary injury. Until recently it was used infrequently. However, because of reduced exposure to open total cholecystectomy in resident training, we recently adopted subtotal cholecystectomy as the bail-out procedure of choice for resident teaching. This study reports our experience and outcomes with subtotal cholecystectomy in the years immediately preceding adoption and since adoption. METHODS: A retrospective analysis was conducted of patients undergoing SC from July 2010 to June 2019. Outcomes, including bile leak, reoperation and need for additional procedures, were analyzed. Complications were graded by the Modified Accordion Grading Scale (MAGS). RESULTS: 1571 cholecystectomies were performed of which 71 were SC. Subtotal cholecystectomy patients had several indicators of difficulty including prior attempted cholecystectomy and previous cholecystostomy tube insertion. The most common indication for SC was marked inflammation in the hepatocystic triangle (51%). As our experience increased, fewer patients required open conversion to accomplish SC and SC was completed laparoscopically, usually subtotal fenestrating cholecystectomy (SFC). Most patients (85%) had a drain placed and 28% were discharged with a drain. The highest MAGS complication observed was grade 3 (11 patients, 15%). Six patients had a bile leak from the cystic duct resolved by ERCP. At mean follow-up of about 1 year no patient returned with recurrent symptoms. CONCLUSIONS: Subtotal fenestrating cholecystectomy is a useful technique to avoid biliary injury in the difficult gallbladder and can be performed with very satisfactory rates of bile fistula, ERCP, and reoperation.

Development of a novel intraoperative difficulty score for minimally invasive cholecystectomy.

BACKGROUND: The rate of biliary injuries from minimally invasive cholecystectomy has remained high for over two decades. To improve outcomes there are multiple bail-out methods described, including aborting the procedure, converting to open, or performing a sub-total cholecystectomy. However, the intraoperative difficulty threshold for when a bail-out method should be implemented is poorly understood. METHODS: From 1/2014 to 2/2019 cholecystectomy videos were collected, de-identified, edited to include the 2-3 minutes when the gallbladder was first visualized, and accelerated. They were then rated on a 5-point difficulty scale. Inter-coder reliability was evaluated using Krippendorff's alpha and regression models were used to evaluate the scores ability to predict the need for a bail-out technique. RESULTS: 62 videos were analyzed with a median length after editing of 37.5 (29.0-43.3) seconds. A median time of 46.2 (38.3-53.4) seconds was required for grading. The bail-out rate was 42.9%. The inter-coder reliability between 2 surgeons and 8 non-clinical reviewers was 0.675 with an average difficulty score of 3.0 (SD = 1.01). Regression models showed that the scale was able to significantly predict conversion (ß=0.56,p<.01). CONCLUSION: This novel difficulty score was able to predict conversion to a bail-out technique early in the course of minimally invasive cholecystectomy.

Thunderbeat™ Integrated Bipolar and Ultrasonic Forceps in the Whipple Procedure: A Prospective Randomized Trial.

Thunderbeat™ is a device that uses both ultrasonic and advanced bipolar energies to achieve hemostasis. It has been evaluated in a variety of clinical contexts, but no literature exists regarding its application to pancreatic surgery. Using a prospective, randomized controlled trial, we evaluated its safety and efficacy in the Whipple procedure. Thirty-two participants were enrolled in the study. The Thunderbeat™ device during the Whipple procedure showed similar safety profile compared to standard of care.