Tumour extracellular vesicles and particles induce liver metabolic dysfunction.

Cancer alters the function of multiple organs beyond those targeted by metastasis1,2. Here we show that inflammation, fatty liver and dysregulated metabolism are hallmarks of systemically affected livers in mouse models and in patients with extrahepatic metastasis. We identified tumour-derived extracellular vesicles and particles (EVPs) as crucial mediators of cancer-induced hepatic reprogramming, which could be reversed by reducing tumour EVP secretion via depletion of Rab27a. All EVP subpopulations, exosomes and principally exomeres, could dysregulate hepatic function. The fatty acid cargo of tumour EVPs-particularly palmitic acid-induced secretion of tumour necrosis factor (TNF) by Kupffer cells, generating a pro-inflammatory microenvironment, suppressing fatty acid metabolism and oxidative phosphorylation, and promoting fatty liver formation. Notably, Kupffer cell ablation or TNF blockade markedly decreased tumour-induced fatty liver generation. Tumour implantation or pre-treatment with tumour EVPs diminished cytochrome P450 gene expression and attenuated drug metabolism in a TNF-dependent manner. We also observed fatty liver and decreased cytochrome P450 expression at diagnosis in tumour-free livers of patients with pancreatic cancer who later developed extrahepatic metastasis, highlighting the clinical relevance of our findings. Notably, tumour EVP education enhanced side effects of chemotherapy, including bone marrow suppression and cardiotoxicity, suggesting that metabolic reprogramming of the liver by tumour-derived EVPs may limit chemotherapy tolerance in patients with cancer. Our results reveal how tumour-derived EVPs dysregulate hepatic function and their targetable potential, alongside TNF inhibition, for preventing fatty liver formation and enhancing the efficacy of chemotherapy.

Personalized RNA neoantigen vaccines stimulate T cells in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is lethal in 88% of patients1, yet harbours mutation-derived T cell neoantigens that are suitable for vaccines 2,3. Here in a phase I trial of adjuvant autogene cevumeran, an individualized neoantigen vaccine based on uridine mRNA-lipoplex nanoparticles, we synthesized mRNA neoantigen vaccines in real time from surgically resected PDAC tumours. After surgery, we sequentially administered atezolizumab (an anti-PD-L1 immunotherapy), autogene cevumeran (a maximum of 20 neoantigens per patient) and a modified version of a four-drug chemotherapy regimen (mFOLFIRINOX, comprising folinic acid, fluorouracil, irinotecan and oxaliplatin). The end points included vaccine-induced neoantigen-specific T cells by high-threshold assays, 18-month recurrence-free survival and oncologic feasibility. We treated 16 patients with atezolizumab and autogene cevumeran, then 15 patients with mFOLFIRINOX. Autogene cevumeran was administered within 3 days of benchmarked times, was tolerable and induced de novo high-magnitude neoantigen-specific T cells in 8 out of 16 patients, with half targeting more than one vaccine neoantigen. Using a new mathematical strategy to track T cell clones (CloneTrack) and functional assays, we found that vaccine-expanded T cells comprised up to 10% of all blood T cells, re-expanded with a vaccine booster and included long-lived polyfunctional neoantigen-specific effector CD8+ T cells. At 18-month median follow-up, patients with vaccine-expanded T cells (responders) had a longer median recurrence-free survival (not reached) compared with patients without vaccine-expanded T cells (non-responders; 13.4 months, P = 0.003). Differences in the immune fitness of the patients did not confound this correlation, as responders and non-responders mounted equivalent immunity to a concurrent unrelated mRNA vaccine against SARS-CoV-2. Thus, adjuvant atezolizumab, autogene cevumeran and mFOLFIRINOX induces substantial T cell activity that may correlate with delayed PDAC recurrence.

Predicting futility of upfront surgery in perihilar cholangiocarcinoma: Machine learning analytics model to optimize treatment allocation.

BACKGROUND: While resection remains the only curative option for perihilar cholangiocarcinoma, it is well known that such surgery is associated with a high risk of morbidity and mortality. Nevertheless, beyond facing life-threatening complications, patients may also develop early disease recurrence, defining a "futile" outcome in perihilar cholangiocarcinoma surgery. The aim of this study is to predict the high-risk category (futile group) where surgical benefits are reversed and alternative treatments may be considered. METHODS: The study cohort included prospectively maintained data from 27 Western tertiary referral centers: the population was divided into a development and a validation cohort. The Framingham Heart Study methodology was used to develop a preoperative scoring system predicting the "futile" outcome. RESULTS: A total of 2271 cases were analyzed: among them, 309 were classified within the "futile group" (13.6%). American Society of Anesthesiology (ASA) score ≥ 3 (OR 1.60; p = 0.005), bilirubin at diagnosis ≥50 mmol/L (OR 1.50; p = 0.025), Ca 19-9 ≥ 100 U/mL (OR 1.73; p = 0.013), preoperative cholangitis (OR 1.75; p = 0.002), portal vein involvement (OR 1.61; p = 0.020), tumor diameter ≥3 cm (OR 1.76; p < 0.001), and left-sided resection (OR 2.00; p < 0.001) were identified as independent predictors of futility. The point system developed, defined three (ie, low, intermediate, and high) risk classes, which showed good accuracy (AUC 0.755) when tested on the validation cohort. CONCLUSIONS: The possibility to accurately estimate, through a point system, the risk of severe postoperative morbidity and early recurrence, could be helpful in defining the best management strategy (surgery vs. nonsurgical treatments) according to preoperative features.

Randomized Prospective Trial of Epidural Analgesia after Open Hepatectomy.

OBJECTIVE: To evaluate whether patient-controlled epidural analgesia (PCEA) improves postoperative pain during ambulation following elective open hepatectomy. BACKGROUND: Strategies to alleviate postoperative pain are a critical element of recovery after surgery. However, the optimal postoperative pain management strategy following open hepatectomy remains unclear. METHODS: We conducted a prospective, nonblinded, randomized comparison of PCEA (intervention) versus intravenous patient-controlled analgesia (IV PCA; control) for postoperative pain following elective open hepatectomy. The primary end point was pain during ambulation on postoperative day (POD) 2. The study was powered to detect a clinically significant 2-point difference on the pain numeric rating scale (NRS). Secondary end points included pain at rest, morbidity, time to return of bowel function, and length of stay. RESULTS: From 2015 to 2020, 231 patients were randomized (116 patients in the PCEA arm and 115 in the IV PCA arm). The incidence of epidural failure was 3% (n=4/116), with no epidural-related complications. Patients in the PCEA arm had a <2-point difference in NRS pain scores during ambulation on POD 2 vs. IV PCA (median 4.0 vs. 5.0, P <0.001). There was no difference in overall complications between the PCEA and IV PCA arms (33% vs. 40%, P =0.276). Secondary outcomes, including pain scores at rest, were similar between the study arms. CONCLUSIONS: PCEA was safe following open hepatectomy and was associated with a small difference in pain with activity on POD 2 that did not reach our pre-specified definition of clinical significance.

Safety of Selective Operative Drainage After Pancreatic Resection: A Retrospective Analysis of 2,607 Patients.

OBJECTIVE: To assess whether selective omission of operative drains after pancreaticoduodenectomy (PD) and distal pancreatectomy (DP) is associated with adverse perioperative outcomes. BACKGROUND: The routine use of operative drains after pancreatectomy is widely practiced; however, prospective randomized clinical trials and retrospective analyses have shown mixed results. METHODS: Patients who underwent PD or DP between November 2009 and May 2021 were reviewed and stratified by operative drain placement. Patient demographics, morbidity, the need for additional procedures, and mortality were compared between patients who did or did not develop a clinically relevant post-operative pancreatic fistula (CR-POPF). RESULTS: In total, 1,855 PD and 752 DP cases were analyzed. Among PD patients with a CR-POPF (N=259, 14%), 160 (62%) had an operative drain placed, of whom 141 (88%) required at least 1 additional procedure. Within this subgroup, grade ≥ 4 complications (7.5% vs. 11.1%, P=0.37), 90-day mortality (3.8% vs. 6.1%, P=0.54), length of stay (LOS) (median 12 vs. 13 d, P=0.19) and readmission rates (63.1% vs. 54.6%, P=0.19) were similar between drained and non-drained patients. Of note, drained PD patients without a CR-POPF had a longer hospital stay (8 vs. 7 d, respectively, P=0.004) and more thromboembolic events (2.4% vs. 1.1%, respectively, P=0.04) Among DP patients with a CR-POPF (n=129), 44 had an operative drain, with 37 (84%) requiring an additional procedure. Within this subgroup, grade ≥ 4 complications (4.6% vs. 5.9%, P>0.95), 90-day mortality (0%), LOS (median 7 d for both, P=0.88) and readmission rates (72.7% vs. 80%, P=0.38) were similar in drained and non-drained patients. CONCLUSION: This study confirms that selective omission of operative drains does not compromise perioperative outcomes, as initially reported in our prospective randomized trial.

Risk Factors for Progression in Patients Undergoing Surveillance for Pancreatic Cysts.

OBJECTIVE: To identify risk factors associated with the progression of pancreatic cysts in patients undergoing surveillance. BACKGROUND: Previous studies of intraductal papillary mucinous neoplasms (IPMNs) rely on surgical series to determine malignancy risk and have inconsistently identified characteristics associated with IPMN progression. METHODS: We conducted a retrospective review of 2197 patients presenting with imaging concerning for IPMN from 2010 to 2019 at a single institution. Cyst progression was defined as resection or pancreatic cancer development. RESULTS: The median follow-up time was 84 months from the presentation. The median age was 66 years, and 62% were female. Ten percent had a first-degree relative with pancreatic cancer, and 3.2% had a germline mutation or genetic syndrome associated with an increased risk of pancreatic ductal adenocarcinoma (PDAC). Cumulative incidence of progression was 17.8% and 20.0% at 12 and 60 months postpresentation, respectively. Surgical pathology for 417 resected cases showed noninvasive IPMN in 39% of cases and PDAC with or without associated IPMN in 20%. Only 18 patients developed PDAC after 6 months of surveillance (0.8%). On multivariable analysis, symptomatic disease [hazard ratio (HR)=1.58; 95% CI: 1.25-2.01], current smoker status (HR=1.58; 95% CI: 1.16-2.15), cyst size (HR=1.26; 95% CI: 1.20-1.33), main duct dilation (HR=3.17; 95% CI: 2.44-4.11), and solid components (HR=1.89; 95% CI: 1.34-2.66) were associated with progression. CONCLUSIONS: Worrisome features on imaging at presentation, current smoker status, and symptomatic presentation are associated with IPMN progression. Most patients progressed within the first year of presentation to Memorial Sloan Kettering Cancer Center (MSKCC). Further investigation is necessary to develop personalized cyst surveillance strategies.

Early-Onset Pancreatic Neuroendocrine Tumors: Clinical Presentation, Pathology Features, and Oncological Outcomes.

BACKGROUND: Early-Onset (EO) pancreatic neuroendocrine tumor (PanNET) is a rare disease, but whether it is clinically different from late-onset (LO) PanNET is unknown. Our study aimed to evaluate clinical differences and disease outcomes between EO-PanNET and LO-PanNET and to compare sporadic EO-PanNET with those with a hereditary syndrome. METHODS: Patients with localized PanNET who underwent pancreatectomy at Memorial Sloan Kettering between 2000 and 2017 were identified. Those with metastatic disease and poorly differentiated tumors were excluded. EO-PanNET was defined as <50 and LO-PanNET >50 years of age at the time of diagnosis. Family history and clinical and pathology characteristics were recorded. RESULTS: Overall 383 patients were included, 107 (27.9%) with EO-PanNET. Compared with LO-PanNET, EO-PanNET were more likely to have a hereditary syndrome (2.2% vs. 16%, P <0.001) but had similar pathology features such as tumor grade ( P =0.6), size (2.2 Vs. 2.3 cm, P =0.5) and stageof disease ( P =0.8). Among patients with EO-PanNET, those with hereditary syndrome had more frequently a multifocal disease (65% vs. 3.3%, P <0.001). With a median follow-up of 70 months (range 0-238), the 5-year cumulative incidence of recurrence after curative surgery was 19% (95% CI 12%-28%) and 17% (95% CI 13%-23%), in EO-PanNET and LO-PanNET ( P =0.3). Five-year disease-specific survival was 99% (95% CI 98%-100%) with no difference with respect to PanNET onset time ( P =0.26). CONCLUSIONS: In this surgical cohort, we found that EO-PanNET is associated with hereditary syndromes but has pathologic characteristics and oncological outcomes similar to LO-PanNET. These findings suggest that patients with EO-PanNET can be managed similarly to those with LO-PanNET.

Clinicogenomic predictors of outcomes in patients with hepatocellular carcinoma treated with immunotherapy.

INTRODUCTION: Immune checkpoint inhibitor (ICI) combinations extend overall survival (OS) while anti-PD-1/L1 monotherapy is non-inferior to sorafenib in treatment-naïve, patients with advanced hepatocellular carcinoma (HCC). Clinicogenomic features are posited to influence patient outcomes. METHODS: The primary objective of this retrospective study was to define the clinical, pathologic, and genomic factors associated with outcomes to ICI therapy in patients with HCC. Patients with histologically confirmed advanced HCC treated with ICI at Memorial Sloan Kettering Cancer Center from 2012 to 2022 were included. Association between clinical, pathological, and genomic characteristics were assessed with univariable and multivariable Cox regression model for progression-free survival (PFS) and OS. RESULTS: Two-hundred and forty-two patients were treated with ICI-based therapy. Patients were predominantly male (82%) with virally mediated HCC (53%) and Child Pugh A score (70%). Median follow-up was 28 months (0.5-78.4). Median PFS for those treated in 1st line, 2nd line and ≥ 3rd line was 4.9 (range: 2.9-6.2), 3.1 (2.3-4.0), and 2.5 (2.1-4.0) months, respectively. Median OS for those treated in 1st line, 2nd line, and ≥ 3rd line was 16 (11-22), 7.5 (6.4-11), and 6.4 (4.6-26) months, respectively. Poor liver function and performance status associated with worse PFS and OS, while viral hepatitis C was associated with favorable outcome. Genetic alterations were not associated with outcomes. CONCLUSION: Clinicopathologic factors were the major determinates of outcomes for patients with advanced HCC treated with ICI. Molecular profiling did not aid in stratification of ICI outcomes. Future studies should explore alternative biomarkers such as the level of immune activation or the pretreatment composition of the immune tumor microenvironment.

Treatment Patterns and Outcomes in Pancreatic Cancer: A Comparative Analysis of Ontario and the USA.

BACKGROUND: Comparative studies evaluating quality of care in different healthcare systems can guide reform initiatives. This study seeks to characterize best practices by comparing utilization and outcomes for patients with pancreatic cancer (PC) in the USA and Ontario, Canada. METHODS: Patients (age ≥ 66 years) with PC were identified from the Ontario Cancer Registry and SEER-Medicare databases from 2006 to 2015. Demographics and treatment (surgery, radiation, chemotherapy, or multimodality (surgery and chemotherapy)) were described. In resected patients, neoadjuvant therapy, readmission, and 30- and 90-day postoperative mortality rates were calculated. Survival was assessed using Kaplan-Meier curves. RESULTS: This study includes 38,858 and 11,512 patients with PC from the USA and Ontario, respectively. More female patients were identified in the USA (54.0%) versus Ontario (46.9%). In the entire cohort, US patients received more radiation in addition to other therapies (18.8% vs. 13.5% Ontario) and chemotherapy alone (34.3% vs. 19.0% Ontario). While rates of resection were similar (13.4% USA vs.12.5% Ontario), multimodality therapy was more common in the UAS (9.0% vs. 6.4%). Among resected patients, neoadjuvant chemotherapy was uncommon in both groups, although more frequent in the USA (12.0% vs. 3.2% Ontario). The 30- and 90-day postoperative mortality rates were lower in Ontario vs. the USA (30-day: 3.26% vs. 4.91%; 90-day: 7.08% vs. 10.96%), however, overall survival was similar between the USA and Ontario. CONCLUSIONS: We observed substantive differences in treatment and outcomes between PC patients in the USA and Ontario, which may reflect known differences in healthcare systems. Close evaluation of healthcare policies can inform initiatives to improve care quality.

Gemcitabine with Cisplatin Versus Hepatic Arterial Infusion Pump Chemotherapy for Liver-Confined Unresectable Intrahepatic Cholangiocarcinoma.

BACKGROUND: A post-hoc analysis of ABC trials included 34 patients with liver-confined unresectable intrahepatic cholangiocarcinoma (iCCA) who received systemic chemotherapy with gemcitabine and cisplatin (gem-cis). The median overall survival (OS) was 16.7 months and the 3-year OS was 2.8%. The aim of this study was to compare patients treated with systemic gem-cis versus hepatic arterial infusion pump (HAIP) chemotherapy for liver-confined unresectable iCCA. METHODS: We retrospectively collected consecutive patients with liver-confined unresectable iCCA who received gem-cis in two centers in the Netherlands to compare with consecutive patients who received HAIP chemotherapy with or without systemic chemotherapy in Memorial Sloan Kettering Cancer Center. RESULTS: In total, 268 patients with liver-confined unresectable iCCA were included; 76 received gem-cis and 192 received HAIP chemotherapy. In the gem-cis group 42 patients (55.3%) had multifocal disease compared with 141 patients (73.4%) in the HAIP group (p = 0.023). Median OS for gem-cis was 11.8 months versus 27.7 months for HAIP chemotherapy (p < 0.001). OS at 3 years was 3.5% (95% confidence interval [CI] 0.0-13.6%) in the gem-cis group versus 34.3% (95% CI 28.1-41.8%) in the HAIP chemotherapy group. After adjusting for male gender, performance status, baseline hepatobiliary disease, and multifocal disease, the hazard ratio (HR) for HAIP chemotherapy was 0.27 (95% CI 0.19-0.39). CONCLUSIONS: This study confirmed the results from the ABC trials that survival beyond 3 years is rare for patients with liver-confined unresectable iCCA treated with palliative gem-cis alone. With HAIP chemotherapy, one in three patients was alive at 3 years.

Higher Postoperative Mortality and Inferior Survival After Right-Sided Liver Resection for Perihilar Cholangiocarcinoma: Left-Sided Resection is Preferred When Possible.

BACKGROUND: A right- or left-sided liver resection can be considered in about half of patients with perihilar cholangiocarcinoma (pCCA), depending on tumor location and vascular involvement. This study compared postoperative mortality and long-term survival of right- versus left-sided liver resections for pCCA. METHODS: Patients who underwent major liver resection for pCCA at 25 Western centers were stratified according to the type of hepatectomy-left, extended left, right, and extended right. The primary outcomes were 90-day mortality and overall survival (OS). RESULTS: Between 2000 and 2022, 1701 patients underwent major liver resection for pCCA. The 90-day mortality was 9% after left-sided and 18% after right-sided liver resection (p < 0.001). The 90-day mortality rates were 8% (44/540) after left, 11% (29/276) after extended left, 17% (51/309) after right, and 19% (108/576) after extended right hepatectomy (p < 0.001). Median OS was 30 months (95% confidence interval [CI] 27-34) after left and 23 months (95% CI 20-25) after right liver resection (p < 0.001), and 33 months (95% CI 28-38), 27 months (95% CI 23-32), 25 months (95% CI 21-30), and 21 months (95% CI 18-24) after left, extended left, right, and extended right hepatectomy, respectively (p < 0.001). A left-sided resection was an independent favorable prognostic factor for both 90-day mortality and OS compared with right-sided resection, with similar results after excluding 90-day fatalities. CONCLUSIONS: A left or extended left hepatectomy is associated with a lower 90-day mortality and superior OS compared with an (extended) right hepatectomy for pCCA. When both a left and right liver resection are feasible, a left-sided liver resection is preferred.

Outcome of patients with perihilar cholangiocarcinoma and previous biliary instrumentation: an observational study.

BACKGROUND: To assess the outcome of previously untreated patients with perihilar cholangiocarcinoma who present to a cancer referral center with or without pre-existing trans-papillary biliary drainage. METHODS: Consecutive patients with a diagnosis of perihilar cholangiocarcinoma presenting between January 1, 2013, and December 31, 2017, were identified from a prospective surgical database and by a query of the institutional database. Of 237 patients identified, 106 met inclusion criteria and were reviewed. Clinical information was obtained from the Electronic Medical Record and imaging studies were reviewed in the Picture Archiving and Communication System. RESULTS: 73 of 106 patients (69%) presenting with a new diagnosis of perihilar cholangiocarcinoma underwent trans-papillary biliary drainage (65 endoscopic and 8 percutaneous) prior to presentation at our institution. 8 of the 73 patients with trans-papillary biliary drainage (11%) presented with and 5 developed cholangitis; all 13 (18%) required subsequent intervention; none of the patients without trans-papillary biliary drainage presented with or required drainage for cholangitis (p = 0.008). Requiring drainage for cholangitis was more likely to delay treatment (p = 0.012) and portended a poorer median overall survival (13.6 months, 95%CI [4.08, not reached)] vs. 20.6 months, 95%CI [18.34, 37.51] p = 0.043). CONCLUSION: Trans-papillary biliary drainage for perihilar cholangiocarcinoma carries a risk of cholangitis and should be avoided when possible. Clinical and imaging findings of perihilar cholangiocarcinoma should prompt evaluation at a cancer referral center before any intervention. This would mitigate development of cholangitis necessitating additional drainage procedures, delaying treatment and potentially compromising survival.

The Influence of Patient Preference on Surgeons' Treatment Recommendations in the Management of Intraductal Papillary Mucinous Neoplasms.

OBJECTIVE: We aimed to determine whether surgeon variation in management of intraductal papillary mucinous neoplasms (IPMN) is driven by differences in risk perception and quantify surgeons' risk threshold for changing their recommendations. BACKGROUND: Surgeons vary widely in management of IPMN. METHODS: We conducted a survey of members of the Americas HepatoPancreatoBiliary Association, presented participants with 2 detailed clinical vignettes and asked them to choose between surgical resection and surveillance. We also asked them to judge the likelihood that the IPMN harbors cancer and that the patient would have a serious complication if surgery was performed. Finally, we asked surgeons to rate the level of cancer risk at which they would change their treatment recommendation. We examined the association between surgeons' treatment recommendations and their risk perception and risk threshold. RESULTS: One hundred and fifty surgeons participated in the study. Surgeons varied in their recommendations for surgery [19% for vignette 1 (V1) and 12% for V2] and in their perception of the cancer risk (interquartile range: 2%-10% for V1 and V2) and risk of surgical complications (V1 interquartile range: 10%-20%, V2 20%-30%). After adjusting for surgeon characteristics, surgeons who were above the median in cancer risk perception were 22 percentage points (27% vs. 5%) more likely to recommend resection than those who were below the median (95% CI: 11.34%; P <0.001). The median risk threshold at which surgeons would change their recommendation was 15% (V1 and V2). Surgeons who recommended surgery had a lower risk threshold for changing their recommendation than those who recommended surveillance (V1: 10.0 vs. 15.0, P =0.06; V2: 7.0 vs. 15.0, P =0.05). CONCLUSIONS: The treatment that patients receive for IPMNs depends greatly on how their surgeons perceive the risk of cancer in the lesion. Efforts to improve cancer risk prediction for IPMNs may lead to decreased variations in care.

Risk Perceptions and Risk Thresholds Among Surgeons in the Management of Intraductal Papillary Mucinous Neoplasms.

OBJECTIVES: We aimed to determine whether surgeon variation in management of intraductal papillary mucinous neoplasm (IPMN) is driven by differences in risk perception and quantify surgeons' risk threshold for changing their recommendations. BACKGROUND: Surgeons vary widely in management of IPMN. METHODS: We conducted a survey of members of the Americas HepatoPancreatoBiliary Association, presented participants with 2 detailed clinical vignettes and asked them to choose between surgical resection and surveillance. We also asked them to judge the likelihood that the IPMN harbors cancer and that the patient would have a serious complication if surgery was performed. Finally, we asked surgeons to rate the level of cancer risk at which they would change their treatment recommendation. We examined the association between surgeons' treatment recommendations and their risk perception and risk threshold. RESULTS: One hundred fifty surgeons participated in the study. Surgeons varied in their recommendations for surgery [19% for vignette 1 (V1) and 12% for V2] and in their perception of the cancer risk (interquartile range: 2%-10% for V1 and V2) and risk of surgical complications (V1 interquartile range: 10%-20%, V2 20-30%). After adjusting for surgeon characteristics, surgeons who were above the median in cancer risk perception were 22 percentage points (27% vs 5%) more likely to recommend resection than those who were below the median (95% CI: 11%-4%; P <0.001). The median risk threshold at which surgeons would change their recommendation was 15% (V1 and V2). Surgeons who recommended surgery had a lower risk threshold for changing their recommendation than those who recommended surveillance (V1: 10.0 vs 15.0, P =0.06; V2: 7.0 vs 15.0, P =0.05). CONCLUSIONS: The treatment that patients receive for IPMNs depends greatly on how their surgeons perceive the risk of cancer in the lesion. Efforts to improve cancer risk prediction for IPMNs may lead to decreased variations in care.

Segmental Versus Diffuse Main Duct Intraductal Papillary Mucinous Neoplasm: Examination of Main Pancreatic Duct Morphology and Implications for Malignancy Risk and Extent of Surgical Resection.

OBJECTIVE: To determine whether the morphologic features of the main pancreatic duct (MPD) of main-duct-involved-intraductal papillary mucinous neoplasm (IPMN) (ie, main duct or mixed main duct/side branch) have implications for the risk of malignancy and extent of resection. BACKGROUND: International consensus guidelines acknowledge the presence of various MPD morphologies (ie, diffuse vs segmental main-duct-involved-IPMN) without a precise definition of each entity and with limited data to guide treatment strategy. METHODS: All consecutive main-duct-involved-IPMN patients (2005-2019) with a MPD diameter ≥5 mm by cross-sectional imaging were reviewed from a prospective institutional database. Morphologic features of the MPD were correlated with the identification of high-grade dysplasia or pancreatic ductal adenocarcinoma (HGD/PDAC) by logistic regression modeling. In patients who underwent partial pancreatectomy, preoperative MPD morphologic features were correlated with the future development of HGD/PDAC in the pancreatic remnant by Cox hazards modeling. RESULTS: In a cohort of 214 main-duct-involved-IPMN patients, the overall rate of HGD/PDAC was 54.2%. MPD morphologic characteristics associated with HGD/PDAC included: maximal MPD diameter (5-10 mm: 29.8%; 10-14 mm: 59.0%; 15-19 mm: 78.6%; ≥20 mm: 95.8%; P <0.001), segmental extent of maximal dilation (<25%: 28.2%; 25%-49%: 54.9%; 50%-74%: 63.1%; ≥75%: 67.9%; P =0.002), and nonsegmental MPD diameter (<5 mm: 21.5% vs ≥5 mm: 78.5%, P <0.001). Diffuse MPD dilation involving ≥90% extent was rare (5.6%). After a median follow-up of 50 months, 7 (7.2%) patients who underwent partial pancreatectomy for IPMN without associated PDAC developed HGD/PDAC in the pancreatic remnant. Maximal MPD diameter, segmental extent of maximal dilation, or nonsegmental MPD diameter were not associated with the development of HGD/PDAC in the pancreatic remnant. However, a mural nodule on preoperative imaging was associated with the development of HGD/PDAC in the pancreatic remnant. CONCLUSIONS: "Diffuse" involvement with homogenous dilation of the MPD was rare. For the majority of patients with segmental main-duct-involved-IPMN, the MPD morphology conferred malignancy risk. Duct morphology was not predictive for the development of HGD or invasive disease in the pancreatic remnant, implying the safety of limited pancreatic resection for initial surgical management.

Surgical Margin of Resected Colorectal Liver Metastases:: How Accurate is Surgeon Prediction?

OBJECTIVE: The aim of this study was to describe the surgeon's ability to accurately predict the margin following resection of colorectal liver metastases (CRLM). SUMMARY BACKGROUND DATA: The decision to resect CRLM is based on the surgeon's ability to predict tumor free resection margins. However, to date, no study has evaluated the accuracy of surgeon margin prediction. METHODS: In this single-institution prospective study, the operating attending and fellow independently completed a preoperative and postoperative questionnaire describing their expected resection margin in 100 consecutive cases (200 assessments) of colorectal liver metastasis resections. In cases with multiple metastases, the closest margin was assessed as the margin of interest for the primary outcome. Surgeon assessments were compared to the gold-standard histopathologic assessment. RESULTS: After excluding aborted cases, 190 preoperative and 190 postoperative assessments from 95 cases were included in the analysis. The pathologic margin was noted to be wide (≥1 cm), 1 mm to 1 cm, narrow (<1 mm), and positive in 28 (29.5%), 55 (57.9%), 5 (5.3%), and 7 (7.4%) cases, respectively. The 88 cases with negative margins were all predicted to be negative. None of the cases with positive margins were predicted to be positive. Ninety-one (48%) preoperative and 104 (55%) postoperative predictions were accurate. The sensitivity of predicting a margin <1 mm was 8.3% preoperatively and 16.7% postoperatively. The positive predictive value for preoperative and postoperative predictions of margin <1 mm was 18.2% and 26.7%, respectively. CONCLUSIONS: Surgeons are inaccurate at predicting positive and close surgical margins following resection of CRLM. A predicted close margin should not necessarily preclude resection.

A Model to Predict Treatment Failure in Patients Undergoing Upfront Surgery for Resectable Colorectal Liver Metastases.

INTRODUCTION: Patients who recur in the first year after resection of colorectal liver metastases (CRLM) do poorly. The aim of our study was to predict treatment failure in patients undergoing upfront resection with a nomogram. METHODS: Data from patients resected between 1991 and 2019 were randomly split (70:30) into two cohorts. Treatment failure was defined as any recurrence or death within 12 months. A nomogram was constructed using multivariable logistic regression on the training cohort and validated using the testing cohort. RESULTS: Overall, 783 patients were included. Primary tumor characteristics included 50% left-sided: 75.2% T3/4 and 56.5% node-positive. The median disease-free interval was 10 months, median number of metastases was 1 (1-50), and with a median size of 3.6 cm (0.2-22); 222 (28.3%) patients recurred within 1 year. Recurrence was mostly extrahepatic with or without liver involvement (150/222, 67.6%). Curative-intent treatment was possible in 37.8% of these patients. Primary location, T-stage and node status, disease-free interval, and number and size of metastases were associated with treatment failure. The area under the curve from the validation of the model was 0.6 (95% confidence interval 0.52-0.68). Patients with a high-risk of treatment failure (≥40%) had a worse survival from the landmark time of 12 months from surgery compared with those with low-risk (2-years: 82% vs. 70%; p = 0.0002). CONCLUSIONS: Primary location, T stage, node status, disease-free interval, and number and size of metastases are associated with treatment failure. The survival of patients with a probability of treatment failure ≥40% is unfavorable. Future trials investigating the role of neoadjuvant therapy in these high-risk patients are warranted.

Rates and Patterns of Recurrence After Microwave Ablation of Colorectal Liver Metastases: A Per Lesion Analysis of 416 Tumors in the Era of 2.45 GHz Generators.

BACKGROUND: For some patients with colorectal liver metastases (CRLMs), surgical resection of all visible disease can lead to long-term survival and even cure. When complete resection is not feasible, microwave ablation (MWA) can help achieve hepatic disease control. As modern 2.45-GHz MWA generators gain popularity, the characteristics of tumors most likely to benefit from this method remain unclear. This study aimed to evaluate local recurrence (LR) rates, patterns of recurrence, and factors contributing to treatment failure after 2.45-GHz MWA of CRLM. METHODS: Patients with CRLM who underwent operative 2.45-GHz MWA between 2011 and 2019 were identified in a prospectively maintained single-institution database. Recurrence outcomes were ascertained for each lesion by imaging review. Factors associated with LR were analyzed. RESULTS: The study enrolled 184 patients bearing 416 ablated tumors. Most of the patients (65.8%) had high clinical risk scores (3-5), and 165 (90%) underwent concurrent liver resection. The median tumor size was 10 mm. After a median follow-up period of 28.8 months, LR was observed in 45 tumors, and the cumulative incidence of LR at 24 months was 10.9% (95% confidence interval [CI], 8.0-14.3%]. In 7%, LR was the first recurrence site, often combined with recurrence elsewhere. The cumulative incidence of LR at 24 months was 6.8% (95% CI 3.8-11.0%) for tumors 10 mm in size or smaller, 12.4% (95% CI 7.8-18.1%) for tumors 11 to 20 mm in size, and 30.2% (95% CI 14.2-48.0%) for tumors larger than 20 mm. In the multivariable analysis, tumors larger than 20 mm with a subcapsular location were significantly associated with increased LR risk. CONCLUSIONS: Treatment of CRLM with 2.45-GHz MWA offers excellent local control at 2 years and is most successful for small tumors deep within the parenchyma.

Combined Hepatic Arterial Infusion Pump and Systemic Chemotherapy in the Modern Era for Chemotherapy-Naive Patients with Unresectable Colorectal Liver Metastases.

PURPOSE: Chemotherapy-naive patients with unresectable colorectal liver metastases (CRLM) have been the best responders to hepatic arterial infusion (HAI) therapy. The current treatment paradigm has drifted away from HAI in the first-line setting. We aimed to analyze outcomes of combined first-line systemic therapy with HAI therapy (HAI+SYS) in the modern era. METHODS: We conducted a retrospective study of consecutive chemotherapy-naive patients with unresectable CRLM who received HAI+SYS between 2003 and 2019. Patients were selected from a prospectively maintained database. Outcomes included radiological response rate, conversion to resection (CTR) rate, and overall survival (OS). RESULTS: Fifty-eight chemotherapy-naive patients were identified out of 546 patients with unresectable CRLM managed with HAI. After induction treatment, 4 patients (7%) had a complete radiological response, including two durable responses. In total, 32 patients (55%) underwent CTR. CTR or complete response without resection was achieved after seven cycles of systemic therapy and four cycles of HAI therapy. Median OS for the whole cohort was 53.0 months (95% confidence interval 23.0-82.9). Three- and 5-year OS in patients who achieved CTR or complete response versus patients who did not was 88% and 72% versus 27% and 0% respectively. Of patients who underwent CTR, complete and major pathological response (no and <10% viable tumor cells, respectively) was observed in 7 (22%) and 12 patients (38%). CONCLUSIONS: Combined HAI+SYS in chemotherapy-naive patients resulted in durable and substantial response in a large proportion of patients. Nearly two-thirds of patients achieved a complete response or proceeded to conversion surgery, which was associated with prolonged survival.

Multivariable prediction model for both 90-day mortality and long-term survival for individual patients with perihilar cholangiocarcinoma: does the predicted survival justify the surgical risk?

BACKGROUND: The risk of death after surgery for perihilar cholangiocarcinoma is high; nearly one in every five patients dies within 90 days after surgery. When the oncological benefit is limited, a high-risk resection may not be justified. This retrospective cohort study aimed to create two preoperative prognostic models to predict 90-day mortality and overall survival (OS) after major liver resection for perihilar cholangiocarcinoma. METHODS: Separate models were built with factors known before surgery using multivariable regression analysis for 90-day mortality and OS. Patients were categorized in three groups: favourable profile for surgical resection (90-day mortality rate below 10 per cent and predicted OS more than 3 years), unfavourable profile (90-day mortality rate above 25 per cent and/or predicted OS below 1.5 years), and an intermediate group. RESULTS: A total of 1673 patients were included. Independent risk factors for both 90-day mortality and OS included ASA grade III-IV, large tumour diameter, and right-sided hepatectomy. Additional risk factors for 90-day mortality were advanced age and preoperative cholangitis; those for long-term OS were high BMI, preoperative jaundice, Bismuth IV, and hepatic artery involvement. In total, 294 patients (17.6 per cent) had a favourable risk profile for surgery (90-day mortality rate 5.8 per cent and median OS 42 months), 271 patients (16.2 per cent) an unfavourable risk profile (90-day mortality rate 26.8 per cent and median OS 16 months), and 1108 patients (66.2 per cent) an intermediate risk profile (90-day mortality rate 12.5 per cent and median OS 27 months). CONCLUSION: Preoperative risk models for 90-day mortality and OS can help identify patients with resectable perihilar cholangiocarcinoma who are unlikely to benefit from surgical resection. Tailored shared decision-making is particularly essential for the large intermediate group.