Tissue-Resident Macrophages in Pancreatic Ductal Adenocarcinoma Originate from Embryonic Hematopoiesis and Promote Tumor Progression.

Tumor-associated macrophages (TAMs) are essential components of the cancer microenvironment and play critical roles in the regulation of tumor progression. Optimal therapeutic intervention requires in-depth understanding of the sources that sustain macrophages in malignant tissues. In this study, we investigated the ontogeny of TAMs in murine pancreatic ductal adenocarcinoma (PDAC) models. We identified both inflammatory monocytes and tissue-resident macrophages as sources of TAMs. Unexpectedly, significant portions of pancreas-resident macrophages originated from embryonic development and expanded through in situ proliferation during tumor progression. Whereas monocyte-derived TAMs played more potent roles in antigen presentation, embryonically derived TAMs exhibited a pro-fibrotic transcriptional profile, indicative of their role in producing and remodeling molecules in the extracellular matrix. Collectively, these findings uncover the heterogeneity of TAM origin and functions and could provide therapeutic insight for PDAC treatment.

Total robotic liver transplant: the final frontier of minimally invasive surgery.

The use of robotic surgery in transplantation is increasing; however, robotic liver transplantation (RLT) remains a challenging undertaking. To our knowledge, this is a report of the first RLT in North America and the first RLT using a whole graft from a deceased donor in the world. This paper describes the preparation leading to the RLT and the surgical technique of the operation. The operation was performed in a 62-year-old man with hepatitis C cirrhosis and hepatocellular carcinoma with a native Model for End-Stage Liver Disease score of 10. The total console time for the operation was 8 hours 30 minutes, and the transplant hepatectomy took 3 hours 30 minutes. Warm ischemia time was 77 minutes. Biliary reconstruction was performed in a primary end-to-end fashion and took 19 minutes to complete. The patient had an uneventful recovery without early allograft dysfunction or surgical complications and continues to do well after 6-months follow-up. This paper demonstrates the feasibility of this operation in highly selected patients with chronic liver disease. Additional experience is required to fully understand the role of RLT in the future of transplant surgery. Narrated video is available at https://youtu.be/TkjDwLryd3I.

Natural history of undifferentiated pleomorphic sarcoma: Experience from the US Sarcoma Collaborative.

BACKGROUND: Undifferentiated pleomorphic sarcoma (UPS) is a relatively rare but aggressive neoplasm. We sought to utilize a multi-institutional US cohort of sarcoma patients to examine predictors of survival and recurrence patterns after resection of UPS. METHODS: From 2000 to 2016, patients with primary UPS undergoing curative-intent surgical resection at seven academic institutions were retrospectively reviewed. Epidemiologic and clinicopathologic factors were reviewed by site of origin. Overall survival (OS), recurrence-free survival (RFS), time-to-locoregional (TTLR), time-to-distant recurrence (TTDR), and patterns of recurrence were analyzed. RESULTS: Of the 534 UPS patients identified, 53% were female, with a median age of 60 and median tumor size of 8.5 cm. The median OS, RFS, TTLR, and TTDR for the entire cohort were 109, 49, 86, and 46 months, respectively. There were no differences in these survival outcomes between extremity and truncal UPS. Compared with truncal, extremity UPS were more commonly amenable to R0 resection (87% vs. 75%, p = 0.017) and less commonly associated with lymph node metastasis (1% vs. 6%, p = 0.031). R0 resection and radiation treatment, but not site of origin (extremity vs. trunk) were independent predictors of OS and RFS. TTLR recurrence was shorter for UPS resected with a positive margin and for tumors not treated with radiation. CONCLUSION: For patients with resected extremity and truncal UPS, tumor size >5 cm and positive resection margin are associated with worse survival OS and RFS, irrespectively the site of origin. R0 surgical resection and radiation treatment may help improve these survival outcomes.

Induction of cancer neoantigens facilitates development of clinically relevant models for the study of pancreatic cancer immunobiology.

Neoantigen burden and CD8 T cell infiltrate are associated with clinical outcome in pancreatic ductal adenocarcinoma (PDAC). A shortcoming of many genetic models of PDAC is the lack of neoantigen burden and limited T cell infiltrate. The goal of the present study was to develop clinically relevant models of PDAC by inducing cancer neoantigens in KP2, a cell line derived from the KPC model of PDAC. KP2 was treated with oxaliplatin and olaparib (OXPARPi), and a resistant cell line was subsequently cloned to generate multiple genetically distinct cell lines (KP2-OXPARPi clones). Clones A and E are sensitive to immune checkpoint inhibition (ICI), exhibit relatively high T cell infiltration, and have significant upregulation of genes involved in antigen presentation, T cell differentiation, and chemokine signaling pathways. Clone B is resistant to ICI and is similar to the parental KP2 cell line in terms of relatively low T cell infiltration and no upregulation of genes involved in the pathways noted above. Tumor/normal exome sequencing and in silico neoantigen prediction confirms successful generation of cancer neoantigens in the KP2-OXPARPi clones and the relative lack of cancer neoantigens in the parental KP2 cell line. Neoantigen vaccine experiments demonstrate that a subset of candidate neoantigens are immunogenic and neoantigen synthetic long peptide vaccines can restrain Clone E tumor growth. Compared to existing models, the KP2-OXPARPi clones better capture the diverse immunobiology of human PDAC and may serve as models for future investigations in cancer immunotherapies and strategies targeting cancer neoantigens in PDAC.

Liver Transplantation After Hepatic Artery Infusion Pump Therapy: Single-Center Experience and Technical Considerations.

BACKGROUND: Hepatic artery infusion pump (HAIP) therapy has become increasingly commonplace in the treatment of intrahepatic tumors. When combined with standard chemotherapy, HAIP therapy demonstrates a higher response rate than chemotherapy alone. Biliary sclerosis is observed in up to 22 % of patients, for whom no treatment has been standardized. This report describes orthotopic liver transplantation (OLT) both as a treatment for HAIP-induced cholangiopathy and as a possible definitive oncologic treatment after HAIP-bridging therapy. METHODS: A retrospective study reviewed patients who had undergone HAIP placement followed by OLT at the authors' institution. Patient demographics, neoadjuvant treatment, and postoperative outcomes were reviewed. RESULTS: Seven OLTs were performed for patients with prior HAIP placement. The majority were women (n = 6), and the median age was 61 years (range, 44.5-65.5 years). Transplantation was performed for five patients due to biliary complications secondary to HAIP and two patients because of residual tumor after HAIP therapy. All the OLTs had difficult dissections due to adhesions. Because of HAIP-induced damage, atypical arterial anastomoses were required in six patients (2 patients used a recipient common hepatic artery below the gastroduodenal artery takeoff; 2 patients used recipient splenic arterial inflow; 1 patient used the junction of the celiac and splenic arteries; and 1 patient used the celiac cuff). The one patient with standard arterial reconstruction experienced an arterial thrombosis. The graft was salvaged with thrombolysis. Biliary reconstruction was duct-to-duct in five cases and Roux-en-Y in two cases. CONCLUSIONS: The OLT procedure is a feasible treatment option for end-stage liver disease after HAIP therapy. Technical considerations include a more challenging dissection and an atypical arterial anastomosis.

The impact of a dedicated operating room team on robotic transplant program growth and fellowship training.

INTRODUCTION: Despite considerable interest in robotic surgery, successful incorporation of robotics into transplant programs has been challenging. Lack of a dedicated OR team with expertise in both robotics and transplant is felt to be a major barrier. This paper assesses the impact of a dedicated robotic transplant team (DART) on program growth and fellowship training at one of the largest robotic transplant programs in North America. METHODS: This is a single center, retrospective review of all robotic operations performed on the transplant surgery service from October 2017 to October 2022. DART was incorporated in February 2020 and included transplant first assists (RFAs), scrub technologists and circulating nurses who received robotic training. Robotic experience before and after DART was compared to assess its impact on program growth and training. RESULTS: Four hundred and two robotic cases were performed by five transplant surgeons: 63 pre-DART and 339 post-DART. 40% of cases were transplant-related and 59.5%, HPB. There was a significant increase in case volume (2.5-10.6 cases/month, p < .0001) and complexity (36.5% vs. 70.3% high complexity cases, p < .0001) post-DART. RFA case coverage increased from 17% to 95%, and participation of transplant fellows as primary surgeons increased from 17% to 95% post-DART period (both p < .05). Conversion rates (9.5% vs. 4.1%) and room turn-around-times (TAT) (58.4 vs. 40.3 min) were lower post-DART (p < .05). There were no emergent conversions, conversions in transplant patients, or robot-related complications in either group. CONCLUSION: OR teams with expertise in robotics and transplant surgery can accelerate growth of robotic transplant programs while maintaining patient safety.

The importance of robotic surgery training in HPB fellowship: a survey of the 2022 AHPBA fellows.

BACKGROUND: The 2022 incoming fellows' expectations for their robotics training, as well as their perceptions of the utility of the surgical robot, are not well defined. METHODS: Cross-sectional survey of 24 AHPBA fellows in 2022, analyzed with descriptive statistics and Spearman's rho. RESULTS: Of 33 current AHPBA fellows, 22 completed the survey (66.7%). Study participants had limited-to-moderate experience with robotics prior to fellowship (mean 2.5 ± SD 1.1; range 1-4). Most participants agreed that robotics influenced their fellowship choice (mean 4.14 ± SD 0.87; range 1-5), would make then more marketable (mean 4.77 ± SD 0.52; range 1-5) and improve job prospects (mean 4.68 ± SD 0.87; range 1-5). Of the study participants, 55% responded that robotics training is "essential" in fellowship, while 64% responded that it is "essential" for their careers. Fellows were only slightly satisfied with overall robotics training within their respective programs (mean 3.44 ± SD 1.17; range 1-5) The majority (73.7%) expect that robotics will comprise <25% of their training. Notably, the majority (75%) have no formal robotics training curriculum. DISCUSSION: This survey identifies potential gaps where robotics training could be improved for future incoming AHPBA fellows.

Extraskeletal myxoid chondrosarcoma: Clinicopathological features and outcomes from the United States sarcoma collaborative database.

BACKGROUNDS AND OBJECTIVES: This investigation described clinicopathological features and outcomes of extraskeletal myxoid chondrosarcoma (EMC) patients. METHODS: EMC patients were identified from the United States Sarcoma Collaborative database between 2000 and 2016. Overall survival (OS) and recurrence-free survival (RFS) were calculated, and prognostic factors were analyzed. RESULTS: Sixty individuals with a mean age of 55 years were included, and 65.0% (n = 39) were male. 73.3% (n = 44) had a primary tumor. A total of 41.6% (n = 25) developed tumor relapse following resection. The locoregional recurrence rate was 30.0% (n = 18/60), and mean follow-up was 42.7 months. The 5-year OS was 71.0%, while the 5-year RFS was 41.4%. On multivariate analysis for all EMC, chemotherapy (hazard ratio [HR], 6.054; 95% confidence interval [CI], 1.33-27.7; p = 0.020) and radiation (HR, 5.07, 95% CI, 1.3-20.1; p = 0.021) were independently predictive of a worse RFS. Among patients with primary EMC only, the 5-year OS was 85.3%, with a 30.0% (n = 12) locoregional recurrence rate, though no significant prognostic factors were identified. CONCLUSIONS: Long-term survival with EMC is probable, however there exists a high incidence of locoregional recurrence. While chemotherapy and radiation were associated with a worse RFS, these findings were likely confounded by recurrent disease as significance was lost in the primary EMC-only subset.

Is a Nomogram Able to Predict Postoperative Wound Complications in Localized Soft-tissue Sarcomas of the Extremity?

BACKGROUND: Postoperative wound complications are challenging in patients with localized extremity soft-tissue sarcomas. Various factors have been associated with wound complications, but there is no individualized predictive model to allow providers to counsel their patients and thus offer methods to mitigate the risk of complications and implement appropriate measures. QUESTIONS/PURPOSES: We used data from multiple centers to ask: (1) What risk factors are associated with postoperative wound complications in patients with localized soft-tissue sarcomas of the extremity? (2) Can we create a predictive nomogram that will assess the risk of wound complications in individual patients after resection for soft-tissue sarcoma? METHODS: From 2000 to 2016, 1669 patients undergoing limb-salvage resection for a localized primary or recurrent extremity soft-tissue sarcoma with at least 120 days of follow-up at eight participating United States Sarcoma Collaborative institutions were identified. Wound complications included superficial wounds with or without drainage, deep wounds with drainage because of dehiscence, and intentional opening of the wound within 120 days postoperatively. Sixteen variables were selected a priori by clinicians and statisticians as potential risk factors for wound complications. A univariate analysis was performed using Fisher's exact tests for categorical predictors, and Wilcoxon's rank-sum tests were used for continuous predictors. A multiple logistic regression analysis was used to train the prediction model that was used to create the nomogram. The prediction performance of the datasets was evaluated using a receiver operating curve, area under the curve, and calibration plot. RESULTS: After controlling for potential confounding factors such as comorbidities, functional status, albumin level, and chemotherapy use, we found that increasing age (odds ratio 1.02; 95% confidence interval, 1.00-1.03; p = 0.008), BMI (OR 1.05; 95% CI, 1.02-1.09; p = 0.004), lower-extremity location (OR 6; 95% CI, 2.87-12.69; p < 0.001), and neoadjuvant radiation (OR 2; 95% CI, 1.47-3.16; p < 0.001) were associated with postoperative wound complications (area under the curve 69.2% [range 62.8%-75.6%]). CONCLUSIONS: We found that age, BMI, tumor location, and timing of radiation are associated with the risk of wound complications. Based on these factors, a validated nomogram has been established that can provide an individualized prediction of wound complications in patients with a resected soft-tissue sarcoma of the extremity. This may allow for proactive management with nutrition and surgical techniques, and help determine the delivery of radiation in patients with a high risk of having these complications. LEVEL OF EVIDENCE: Level III, therapeutic study.

Outcomes of Elderly Patients Undergoing Curative Resection for Retroperitoneal Sarcomas: Analysis From the US Sarcoma Collaborative.

BACKGROUND: The postoperative outcomes of elderly patients undergoing resection of retroperitoneal sarcomas (RPS) have not been widely studied. METHODS: Patients undergoing surgical resection for primary or recurrent RPS between 2000 and 2015 at participating US Sarcoma Collaborative institutions were identified. Patient demographics, perioperative morbidity, mortality, length of stay, discharge to home, disease-specific survival, and disease-free survival were compared between elderly (≥70 y, n = 171) and nonelderly (<70 y, n = 494) patients. RESULTS: There was no difference in perioperative morbidity (total and major complications elderly versus nonelderly: 39% versus 35%; P = 0.401 and 18% versus 17%; P = 0.646, respectively) or mortality between elderly and nonelderly patients with each group experiencing a 1% 30-d mortality rate. Length of stay and 30-d readmission rates were similar (elderly versus nonelderly; 7 d interquartile range [IQR: 5-9] versus 6 d [IQR: 4-9], P = 0.528 and 11% versus 12%, P = 0.667). Elderly patients were more likely to be discharged to a skilled nursing or rehabilitation facility (elderly versus nonelderly; 19% versus 7%, P < 0.001). There was no difference in 3-y disease-free survival between the elderly and nonelderly patients (41% versus 43%, P = 0.65); however, elderly patients had a lower 3-y disease-specific survival (60% versus 76%, P < 0.001). In elderly patients, the presence of multiple comorbidities and high-grade tumors were most predictive of outcomes. CONCLUSIONS: Advanced age was not associated with an increased risk of perioperative morbidity and mortality following resection of RPS in this multi-institutional review. Although short-term oncologic outcomes were similar in both groups, the risk of death after sarcoma recurrence was higher in elderly patients and may be related to comorbidity burden and tumor histology.

Targeting both tumour-associated CXCR2+ neutrophils and CCR2+ macrophages disrupts myeloid recruitment and improves chemotherapeutic responses in pancreatic ductal adenocarcinoma.

OBJECTIVE: Chemokine pathways are co-opted by pancreatic adenocarcinoma (PDAC) to facilitate myeloid cell recruitment from the bone marrow to establish an immunosuppressive tumour microenvironment (TME). Targeting tumour-associated CXCR2+neutrophils (TAN) or tumour-associated CCR2+ macrophages (TAM) alone improves antitumour immunity in preclinical models. However, a compensatory influx of an alternative myeloid subset may result in a persistent immunosuppressive TME and promote therapeutic resistance. Here, we show CCR2 and CXCR2 combined blockade reduces total tumour-infiltrating myeloids, promoting a more robust antitumour immune response in PDAC compared with either strategy alone. METHODS: Blood, bone marrow and tumours were analysed from PDAC patients and controls. Treatment response and correlative studies were performed in mice with established orthotopic PDAC tumours treated with a small molecule CCR2 inhibitor (CCR2i) and CXCR2 inhibitor (CXCR2i), alone and in combination with chemotherapy. RESULTS: A systemic increase in CXCR2+ TAN correlates with poor prognosis in PDAC, and patients receiving CCR2i showed increased tumour-infiltrating CXCR2+ TAN following treatment. In an orthotopic PDAC model, CXCR2 blockade prevented neutrophil mobilisation from the circulation and augmented chemotherapeutic efficacy. However, depletion of either CXCR2+ TAN or CCR2+ TAM resulted in a compensatory response of the alternative myeloid subset, recapitulating human disease. This was overcome by combined CCR2i and CXCR2i, which augmented antitumour immunity and improved response to FOLFIRINOX chemotherapy. CONCLUSION: Dual targeting of CCR2+ TAM and CXCR2+ TAN improves antitumour immunity and chemotherapeutic response in PDAC compared with either strategy alone.

A novel, simplified, externally validated staging system for truncal/extremity soft tissue sarcomas: An analysis of the US Sarcoma Collaborative database.

BACKGROUND: The 8th edition AJCC staging system for truncal/extremity soft tissue sarcoma (STS) offers significant changes from the 7th. However the complexity of both limits their clinical utility. METHODS: Patients with truncal/extremity STS undergoing resection from 2000 to 2016 at seven institutions of the US Sarcoma Collaborative were analyzed. The proposed staging system was externally validated using the National Cancer Database (NCDB). RESULTS: Of 1318 patients, mean age was 59 years, and 54% were male. Median tumor size was 9 cm; 72% were high grade. Applying 8th edition staging, there was no differentiation between stages IA/IB ( P = 0.92), and clinically similar outcomes between stages II/IIIA. Receiver operating characteristic (ROC) analysis identified 7.5 cm as the ideal tumor size discriminating 5-year OS for high-grade tumors. Therefore, a simplified staging system defining all low-grade tumors as stage I, high-grade < 7.5 cm as stage II, high-grade > 7.5 cm as stage III, and metastatic disease as stage IV improved stratification (all P < 0.05). The C-statistic was noninferior to the 8th edition. External validation in the NCDB confirmed optimal stratification (all P < 0.01). CONCLUSIONS: Our proposed staging system maintains prognostic significance between stages within a simplified system. For high-grade tumors, a cutoff of 7.5 cm, instead of 5 cm, maintains discrimination for survival and could be a more clinically applicable cutoff for future clinical trials.

Multi-visceral resection of locally advanced extra-pancreatic carcinoma.

BACKGROUND: Multi-visceral resection for extra-pancreatic carcinoma is an uncommon procedure that may offer palliation and potential cure but must be balanced against the risk for morbidity and mortality. METHODS: A retrospective analysis was made of patients who had undergone multi-visceral resection of non-pancreatic carcinoma. Factors influencing this procedure included histology, pathologic confirmation of pancreaticoduodenal invasion, tumor clearance, peri-operative morbidity and outcome. RESULTS: Sixteen patients had en bloc resection including a Whipple procedure (6 patients) and a distal resection (10). Primary pathology mostly originated from the stomach and adenocarcinoma was predominately histological. An R0 resection was made in 13 patients, and actual cancer invasion or abutment into the pancreas or duodenum was confirmed pathologically in 11 patients. Twelve patients suffered from at least one complication. Ten patients required therapeutic intervention for complications. There were 2 in-hospital deaths. The median survival of deceased patients was 7.5 months. Six patients are alive at a median of 21 months, and 4 patients have no evidence of disease to the present. CONCLUSIONS: Multi-visceral resections for extra-pancreatic carcinoma are associated with substantial morbidity that requires therapeutic intervention. Clinical determination of pancreaticoduodenal abutment and achievement of tumor clearance is excellent. Survival with and without recurrent disease is often limited, supporting that it is necessary to cautiously perform the aggressive procedures in consideration of neoadjuvant therapy.

Robotic performance metrics model fellow proficiency in living donor nephrectomy.

We investigated the use of robotic objective performance metrics (OPM) to predict number of cases to proficiency and independence among abdominal transplant fellows performing robot-assisted donor nephrectomy (RDN). 101 RDNs were performed by 5 transplant fellows from September 2020 to October 2023. OPM included fellow percent active control time (%ACT) and handoff counts (HC). Proficiency was defined as ACT ≥ 80% and HC ≤ 2, and independence as ACT ≥ 99% and HC ≤ 1. Case number was significantly associated with increasing fellow %ACT, with proficiency estimated at 14 cases and independence at 32 cases (R2 = 0.56, p < 0.001). Similarly, case number was significantly associated with decreasing HC, with proficiency at 18 cases and independence at 33 cases (R2 = 0.29, p < 0.001). Case number was not associated with total active console time (p = 0.91). Patient demographics, operative characteristics, and outcomes were not associated with OPM, except for donor estimated blood loss (EBL), which positively correlated with HC. Abdominal transplant fellows demonstrated proficiency at 14-18 cases and independence at 32-33 cases. Total active console time remained unchanged, suggesting that increasing fellow autonomy does not impede operative efficiency. These findings may serve as a benchmark for training abdominal transplant surgery fellows independently and safely in RDN.

Cross-fellowship Inter-institutional Exchange: Answering the Call for Hepatopancreatobiliary Training Standardization.

OBJECTIVE: General surgery trainees interested in performing hepatopancreatobiliary (HPB) surgery can choose from multiple fellowship pathways, namely HPB, surgical oncology (SO), and abdominal transplant-HPB (TXP-HPB). Although focused on similar operations, each program offers distinct clinical and technical emphases. DESIGN: An annual inter-institutional exchange between TXP-HPB and SO fellowships, starting in 2014. SETTING AND PARTICIPANTS: TXP-HPB fellows from Washington University in St. Louis (WUSTL) and SO fellows from Memorial Sloan Kettering Cancer Center (MSKCC). RESULTS: About 14 fellows have participated in the exchange so far, 13 of whom responded to our survey. At MSKCC, TXP-HPB fellows performed a median of 24 cases, including 6 major pancreatic resections, 3 major hepatectomies, 4 hepatic artery infusion pump insertions, and 1 major biliary case. At WUSTL, SO fellows performed a median of 16 cases, including 5 liver transplants, 2 major pancreatic resections, 2 major hepatectomies, and 2 major biliary cases. About 92.3% of respondents stated they would repeat the rotation, with SO fellows emphasizing the exposure to vascular anastomoses and transplant-HPB fellows appreciating the oncologic focus. CONCLUSIONS: A monthlong inter-institutional exchange offers a unique opportunity to standardize and improve HPB education.

A novel assessment model for teaching robot-assisted living donor nephrectomy in abdominal transplant surgery fellowship.

BACKGROUND: An increasing number of transplant centers have adopted robot-assisted living donor nephrectomy. Thus, a transplant fellow assessment tool is needed for promoting operative independence in an objective and safe manner. METHODS: In this pilot study, data was prospectively collected on both fellow performance with focus on technique, efficiency, and communication ("overall RO-SCORE"), and operative steps ("operative steps RO-SCORE"). Robotic user performance metrics were analyzed from the da Vinci Xi system, including fellow percent active control time (ACT) and handoff counts. RESULTS: From July 2020 to February 2021, twenty-one robot-assisted donor nephrectomies were performed. In regression analysis, fellow performance (based on both RO-SCOREs and robot % ACT) was significantly associated with both time and case number, with time-to-independence modelled at 8.4-14.2 months, and case number-to-independence estimated at 15-22 cases. Robot user metrics provided valid objective measures alongside RO-SCOREs. CONCLUSIONS: This pilot study provides an effective assessment tool for promoting operative competency in robot-assisted donor nephrectomy among transplant fellows.