Computed Tomography-Based Radiomics with Machine Learning Outperforms Radiologist Assessment in Estimating Colorectal Liver Metastases Pathologic Response After Chemotherapy.

OBJECTIVES: This study was designed to assess computed tomography (CT)-based radiomics of colorectal liver metastases (CRLM), extracted from posttreatment scans in estimating pathologic treatment response to neoadjuvant therapy, and to compare treatment response estimates between CT-based radiomics and radiological response assessment by using RECIST 1.1 and CT morphologic criteria. METHODS: Patients who underwent resection for CRLM from January 2003-December 2012 at a single institution were included. Patients who did not receive preoperative systemic chemotherapy, or without adequate imaging, were excluded. Imaging characteristics were evaluated based on RECIST 1.1 and CT morphologic criteria. A machine-learning model was designed with radiomic features extracted from manually segmented posttreatment CT tumoral and peritumoral regions to identify pathologic responders (≥ 50% response) versus nonresponders. Statistical analysis was performed at the tumor level. RESULTS: Eighty-five patients (median age, 62 years; 55 women) with 95 tumors were included. None of the subjectively evaluated imaging characteristics were associated with pathologic response (p > 0.05). Inter-reader agreement was substantial for RECIST categorical response assessment (K = 0.70) and moderate for CT morphological group response (K = 0.50). In the validation cohort, the machine learning model built with radiomic features obtained an area under the curve (AUC) of 0.87 and outperformed subjective RECIST assessment (AUC = 0.53, p = 0.01) and morphologic assessment (AUC = 0.56, p = 0.02). CONCLUSIONS: Radiologist assessment of oligometastatic CRLM after neoadjuvant therapy using RECIST 1.1 and CT morphologic criteria was not associated with pathologic response. In contrast, a machine-learning model based on radiomic features extracted from tumoral and peritumoral regions had high diagnostic performance in assessing responders versus nonresponders.

Adjuvant Modified FOLFIRINOX for Resected Pancreatic Adenocarcinoma (PDAC): Clinical Insights and Genomic Features from a Large Contemporary Cohort.

BACKGROUND: Adjuvant mFOLFIRINOX (mFFX) is standard of care for fit individuals with resected pancreatic ductal adenocarcinoma (PDAC). There are limited data on adjuvant mFFX outcomes outside clinical trials. METHODS: Institutional databases queried to identify patients with resected PDAC who received ≥1 dose adjuvant mFFX. Primary endpoints: recurrence free survival (RFS), overall survival (OS). Secondary endpoints: clinical factors, genomic features associated with outcomes. RFS and OS were estimated with Kaplan-Meier. Cox proportional hazards regression model was used to associate clinico-genomic features correlated with survival outcomes. RESULTS: N = 147 identified between 01/2015-01/2023. Median age: 67 years; N = 57 (39%) >70 years. Unfavorable prognostic features: N = 52 (36%) N2 nodal status, N = 115 (78%) lymphovascular invasion), and N = 133 (90%) perineural invasion. Median time from surgery to start mFFX: 1.78 months (m) (IQR 1.45, 2.12). N = 124 (84%) completed 12 doses; N = 98 (67%) stopped oxaliplatin early for neuropathy (median 10 doses; range 4-12). Further dosing characteristics are summarized in Supplementary Table 3. With median follow up of 35.1 m, median RFS (mRFS) 26 m (95% CI 19, 39) and median OS (mOS) not reached. For >70 cohort, mRFS 23 m (95% CI 14, NR) and mOS 51 m (95% CI 37, NR). mFFX started <8 weeks from resection associated with improved RFS (HR 0.62; 95% CI 0.41, 0.96; p = .033) and OS (HR 0.53; 95% CI 0.3, 0.94; p = .030). KRAS mutation and whole genome doubling trended to shorter RFS and OS. Homologous recombination deficiency status did not confer improved survival outcomes. CONCLUSIONS: Adjuvant mFFX is effective and tolerable in resected PDAC in a non-trial setting, including for patients >70 years.

Genome-Derived Ampullary Adenocarcinoma Classifier and Postresection Prognostication.

Importance: Ampullary adenocarcinoma (AA) is characterized by clinical and genomic heterogeneity. A previously developed genomic classifier defined biologically distinct phenotypes with greater accuracy than standard histologic classification. External validation is needed before routine clinical use. Objective: To test external validity of the prognostic value of the hidden genome classifier of AA. Design, Setting, and Participants: This retrospective cohort study took place at 6 international academic institutions. Consecutive patients (n = 192) who underwent curative-intent resection of histologically confirmed AA were included. The data were analyzed from January 2005 through July 2020. Exposures: The multilevel meta-feature regression model previously trained on a prospectively sequenced cohort of 3411 patients (1001 pancreatic adenocarcinoma, 165 distal bile duct adenocarcinoma, and 2245 colorectal adenocarcinoma) was applied to AA sequencing data to quantify the relative proportions of parental cell of origin. Main Outcome and Measures: Genomic classification was correlated with immunohistologic subtype (intestinal [INT] or pancreatobiliary [PB]) and with overall survival (OS), using the log-rank test and Cox proportional hazard models. Results: Among 192 patients with AA (median age, 69.0 [IQR, 60.0-74.0] years and 134 were male [64%]), concordance between immunohistologic and genomic subtypes was 55%. Most INT subtype tumors were categorized into the colorectal genomic subtype (43 of 57 [72.9%]). Of the 114 PB subtype tumors, 29 had a pancreatic genomic profile (25.4%) and 24 had a distal bile duct genomic profile (21.1%). Whereas the standard immunohistologic subtypes were not associated with survival (log rank P = .26), predicted genomic probabilities were correlated with survival probability. Genomic scores with higher colorectal probability were associated with higher survival probability; higher pancreatic and distal bile duct probabilities were associated with lower survival probability. Conclusions and Relevance: The AA genomic classifier is reproducible with available molecular testing in a diverse international cohort of patients and improves stratification of the divergent clinical outcomes beyond standard immunohistologic classification. These data provide a molecular classification that may be incorporated into clinical trials for prospective validation.

Long term outcomes in patients with advanced intrahepatic cholangiocarcinoma treated with hepatic arterial infusion chemotherapy.

INTRODUCTION: Hepatic artery infusion (HAI) of chemotherapy has demonstrated disease control and suggested improvement in overall survival (OS) in intrahepatic cholangiocarcinoma (IHC). We report herein the long-term results and role of molecular alterations of a phase II clinical trial of HAI chemotherapy plus systemic chemotherapy, with a retrospective cohort of patients treated with HAI at Memorial Sloan Kettering Cancer Center. METHODS: This secondary analysis of a single-institution, phase 2 trial and retrospective cohort of unresectable IHC treated with HAI floxuridine (FUDR) plus systemic gemcitabine and oxaliplatin. The primary aim was to assess long-term oncologic outcomes. A subset underwent tissue-based genomic sequencing, and molecular alterations were correlated with progression-free survival (PFS) and OS. RESULTS: Thirty-eight patients were treated on trial with a median follow up of 76.9 months. Median PFS was 11.8 months (95% CI11-15.1). The median OS was 26.8 months (95% CI20.9-40.6). The 1-, 2- and 5-year OS rate was 89.5%, 55%, and 21% respectively. Nine (24%) received HAI with mitomycin C post FUDR progression with an objective response rate of 44% and a median PFS of 3.93 (2.33-NR) months. One-hundred and seventy patients not treated on the clinical trial were included in a retrospective analysis. Median PFS and OS was 7.93 (95%CI: 7.27-10.07) and 22.5 (95%CI : 19.5-28.3) months, respectively. Alterations in the TP53 and cell-cycle pathway had a worse PFS to HAI based therapy compared to wildtype disease. CONCLUSION: In locally advanced IHC, HAI with FUDR in combination with systemic therapy can offer long term durable disease control. Molecular alterations may predict for response.

A NSQIP-Based Randomized Clinical Trial Evaluating Choice of Prophylactic Antibiotics for Pancreaticoduodenectomy.

Surgical site infection is a common complication following pancreaticoduodenectomy and is a major source of postoperative morbidity. Surgical site infection is more common among patients who undergo preoperative biliary instrumentation, likely because of the introduction of intestinal flora into the normally sterile biliary tree. Frequently, bacterial isolates from surgical site infections after pancreaticoduodenectomy demonstrate resistance to the antibiotic agents typically used for surgical prophylaxis, suggesting that broad-spectrum coverage may be beneficial. This chapter summarizes the current evidence regarding surgical site infection following pancreatic surgery and describes the rationale and methodology underlying a multicenter randomized trial evaluating piperacillin-tazobactam compared with cefoxitin for surgical site infection prevention following pancreaticoduodenectomy. As the first U.S. randomized surgical trial to utilize a clinical registry for data collection, this study serves as proof of concept for registry-based clinical trials. The trial has successfully completed patient accrual, and study results are forthcoming.

Extrahepatic Cholangiocarcinoma: Genomic Variables Associated With Anatomic Location and Outcome.

PURPOSE: This study aimed to define genomic differences between perihilar cholangiocarcinoma (PCA) and distal cholangiocarcinoma (DCA) and identify genomic determinants of survival. MATERIALS AND METHODS: Consecutive patients with ECA with tissue for targeted next-generation sequencing were analyzed, stratified by anatomic site (PCA/DCA), disease extent, and treatment. Associations between genomic alterations, clinicopathologic features, and outcomes were analyzed using Cox proportional hazards regression to compare survival. RESULTS: In total, 224 patients diagnosed between 2004 and 2022 (n = 127 PCA; n = 97 DCA) met inclusion criteria. The median survival was 29 months (43 after resection and 17 from diagnosis for unresectable disease). Compared with PCA, DCA was enriched in TP53alt (alterations; 69% v 33%; Q < 0.01), epigenetic pathway alterations (45% v 29%; Q = 0.041), and had more total altered pathways (median 3 v 2; Q < 0.01). KRASalt frequency was similar between PCA (36%) and DCA (37%); however, DCA was enriched in KRAS G12D (19% v 9%; P = .002). No other clinicopathologic or genomic variables distinguished subtypes. In resected patients, no genomic alterations were associated with outcome. However, in unresectable patients, CDKN2Aalt (hazard ratio [HR], 2.59 [1.48 to 4.52]) and APCalt (HR, 5.11 [1.96 to 13.3]) were associated with reduced survival. For the entire cohort, irresectability (HR, 3.13 [2.25 to 4.36]), CDKN2Aalt (HR, 1.80 [1.80 to 2.68]), and APCalt (HR, 2.00 [1.04 to 3.87]) were associated with poor survival. CONCLUSION: CDKN2Aalt and APCalt were associated with poor survival in ECA, primarily in advanced disease. As PCA and DCA were genetically similar, coanalysis of PCA and DCA in future genomic studies is reasonable.

Has Management of Intrahepatic Cholangiocarcinoma Evolved with the Evidence? Trends and Practice Patterns from the National Cancer Database.

BACKGROUND: Management of intrahepatic cholangiocarcinoma (IHC) has advanced in recent decades, including randomized trial evidence supporting systemic therapy in the palliative and adjuvant setting. Mounting observational evidence suggests resection of IHC with multifocal disease (IHC-MF) or lymph node metastasis (IHC-LNM) should be limited. It is unknown how real-world practice has evolved in light of research advances. This study characterizes trends in management and outcomes of IHC without distant metastasis. METHODS: We queried the National Cancer Database (NCDB) for patients treated for IHC without distant metastasis (M0) and identified subgroups with lymph node (cN1) or multifocal hepatic involvement (cT2b). Two-sided Cochran-Armitage tests evaluated trends in initial treating modality and perioperative chemotherapy. Logistic regression evaluated associations with choice of initial treating modality. Overall survival (OS) was evaluated by using Kaplan-Meier methods. RESULTS: Between 2004 and 2020, 11,368 patients were treated for IHC without extrahepatic metastasis. Forty-three percent underwent resection. Initial management shifted from resection towards radiation or systemic therapy in IHC-MF and IHC-LNM. Use of perioperative chemotherapy increased from 39% pre-2010 to 70% in 2018-2020 (p < 0.001), most often delivered postoperatively. Across the entire cohort, median OS improved from 16 (95% confidence interval [CI] 15-18) to 27 months (95% CI 26-29). More modest improvements were observed in IHC-MF and IHC-LNM. CONCLUSIONS: Use of perioperative chemotherapy has been widely adopted, predating randomized trial evidence in the adjuvant setting. Initial management of IHC-MF and IHC-LNM has shifted from resection to systemic and/or radiation therapy. While OS has improved overall, outcomes of IHC-MF and IHC-LNM remain poor, warranting further investigation.

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.

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.

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.

Hemorrhage Sites and Mitigation Strategies After Pancreaticoduodenectomy.

Importance: Postpancreatectomy hemorrhage is an uncommon but highly morbid complication of pancreaticoduodenectomy. Clinical evidence often draws suspicion to the gastroduodenal artery stump, even without a clear source. Objective: To determine the frequency of gastroduodenal artery bleeding compared to other sites and the results of mitigation strategies. Design, Setting, and Participants: This cohort study involved a retrospective analysis of data for consecutive patients who had pancreaticoduodenectomy from 2011 to 2021 at Memorial Sloan Kettering Cancer Center (MSK) and Thomas Jefferson University Hospital (TJUH). Exposures: Demographic, perioperative, and disease-related variables. Main Outcomes and Measures: The incidence, location, treatment, and outcomes of primary (initial) and secondary (recurrent) hemorrhage requiring invasive intervention were analyzed. Imaging studies were re-reviewed by interventional radiologists to confirm sites. Results: Inclusion criteria were met by 3040 patients (n = 1761 MSK, n = 1279 TJUH). Patients from both institutions were similar in age (median [IQR] age at MSK, 67 [59-74] years, and at TJUH, 68 [60-75] years) and sex (at MSK, 814 female [46.5%] and 947 male [53.8%], and at TJUH, 623 [48.7%] and 623 male [51.3%]). Primary hemorrhage occurred in 90 patients (3.0%), of which the gastroduodenal artery was the source in 15 (16.7%), unidentified sites in 24 (26.7%), and non-gastroduodenal artery sites in 51 (56.7%). Secondary hemorrhage occurred in 23 patients; in 4 (17.4%), the gastroduodenal artery was the source. Of all hemorrhage events (n = 117), the gastroduodenal artery was the source in 19 (16.2%, 0.63% incidence in all pancreaticoduodenectomies). Gastroduodenal artery hemorrhage was more often associated with soft gland texture (14 [93.3%] vs 41 [62.1%]; P = .02) and later presentation (median [IQR], 21 [15-26] vs 10 days [5-18]; P = .002). Twenty-three patients underwent empirical gastroduodenal artery embolization or stent placement, 7 (30.4%) of whom subsequently experienced secondary hemorrhage. Twenty percent of all gastroduodenal artery embolizations/stents (8/40 patients), including 13% (3/13 patients) of empirical treatments, were associated with significant morbidity (7 hepatic infarction, 4 biliary stricture), with a 90-day mortality rate of 38.5% (n = 5) for patients with these complications vs 7.8% without (n = 6; P = .008). Ninety-day mortality was 12.2% (n = 11) for patients with hemorrhage (3 patients [20%] with primary gastroduodenal vs 8 [10.7%] for all others; P = .38) compared with 2% (n = 59) for patients without hemorrhage. Conclusions and Relevance: In this study, postpancreatectomy hemorrhage was uncommon and the spectrum was broad, with the gastroduodenal artery responsible for a minority of bleeding events. Empirical gastroduodenal artery embolization/stent without obvious sequelae of recent hemorrhage was associated with significant morbidity and rebleeding and should not be routine practice. Successful treatment of postpancreatectomy hemorrhage requires careful assessment of all potential sources, even after gastroduodenal artery mitigation.

Hepatic arterial infusion pump chemotherapy combined with systemic chemotherapy for borderline resectable and unresectable colorectal liver metastases: phase II feasibility study.

BACKGROUND: Hepatic arterial infusion pump chemotherapy combined with systemic chemotherapy (HAIP-SYS) for liver-only colorectal liver metastases (CRLMs) has shown promising results but has not been adopted worldwide. This study evaluated the feasibility of HAIP-SYS in the Netherlands. METHODS: This was a single-arm phase II study of patients with CRLMs who received HAIP-SYS consisting of floxuridine with concomitant systemic FOLFOX or FOLFIRI. Main inclusion and exclusion criteria were borderline resectable or unresectable liver-only metastases, suitable arterial anatomy and no previous local treatment. Patients underwent laparotomy for pump implantation and primary tumour resection if in situ. Primary end point was feasibility, defined as ≥70% of patients completing two cycles of HAIP-SYS. Sample size calculations led to 31 patients. Secondary outcomes included safety and tumour response. RESULTS: Thirty-one patients with median 13 CRLMs (i.q.r. 6-23) were included. Twenty-eight patients (90%) received two HAIP-SYS cycles. Three patients did not get two cycles due to extrahepatic disease at pump placement, definitive pathology of a recto-sigmoidal squamous cell carcinoma, and progressive disease. Five patients experienced grade 3 surgical or pump device-related complications (16%) and 11 patients experienced grade ≥3 chemotherapy toxicity (38%). At first radiological evaluation, disease control rate was 83% (24/29 patients) and hepatic disease control rate 93% (27/29 patients). At 6 months, 19 patients (66%) had experienced grade ≥3 chemotherapy toxicity and the disease control rate was 79%. CONCLUSION: HAIP-SYS for borderline resectable and unresectable CRLMs was feasible and safe in the Netherlands. This has led to a successive multicentre phase III randomized trial investigating oncological benefit (EUDRA-CT 2023-506194-35-00). Current trial registration number: clinicaltrials.gov (NCT04552093).

Comparison study of intraoperative surface acquisition methods on registration accuracy for soft-tissue surgical navigation.

Purpose: To study the difference between rigid registration and nonrigid registration using two forms of digitization (contact and noncontact) in human in vivo liver surgery. Approach: A Conoprobe device attachment and sterilization process was developed to enable prospective noncontact intraoperative acquisition of organ surface data in the operating room (OR). The noncontact Conoprobe digitization method was compared against stylus-based acquisition in the context of image-to-physical registration for image-guided surgical navigation. Data from n=10 patients undergoing liver resection were analyzed under an Institutional Review Board-approved study at Memorial Sloan Kettering Cancer Center. Organ surface coverage of each surface acquisition method was compared. Registration accuracies resulting from the acquisition techniques were compared for (1) rigid registration method (RRM), (2) model-based nonrigid registration method (NRM) using surface data only, and (3) NRM with one subsurface feature (vena cava) from tracked intraoperative ultrasound (NRM-VC). Novel vessel centerline and tumor targets were segmented and compared to their registered preoperative counterparts for accuracy validation. Results: Surface data coverage collected by stylus and Conoprobe were 24.6%±6.4% and 19.6%±5.0%, respectively. The average difference between stylus data and Conoprobe data using NRM was -1.05 mm and using NRM-VC was -1.42 mm, indicating the registrations to Conoprobe data performed worse than to stylus data with both NRM approaches. However, using the stylus and Conoprobe acquisition methods led to significant improvement of NRM-VC over RRM by average differences of 4.48 and 3.66 mm, respectively. Conclusion: The first use of a sterile-field amenable Conoprobe surface acquisition strategy in the OR is reported for open liver surgery. Under clinical conditions, the nonrigid registration significantly outperformed standard-of-care rigid registration, and acquisition by contact-based stylus and noncontact-based Conoprobe produced similar registration results. The accuracy benefits of noncontact surface acquisition with a Conoprobe are likely obscured by inferior data coverage and intrinsic noise within acquisition systems.

Concordance in Oncogenic Alterations Between the Primary Tumor and Advanced Disease: Insights Into the Heterogeneity of Intrahepatic Cholangiocarcinoma.

PURPOSE: Intrahepatic cholangiocarcinoma (ICCA) is characterized by significant phenotypic and clinical heterogeneities and poor response to systemic therapy, potentially related to underlying heterogeneity in oncogenic alterations. We aimed to characterize the genomic heterogeneity between primary tumors and advanced disease in patients with ICCA. METHODS: Biopsy-proven CCA specimens (primary tumor and paired advanced disease [metastatic disease, progressive disease on systemic therapy, or postoperative recurrence]) from two institutions were subjected to targeted next-generation sequencing. Overall concordance (oncogenic driver mutations, copy number alterations, and fusion events) and mutational concordance (only oncogenic mutations) were compared across paired samples. A subgroup analysis was performed on the basis of exposure to systemic therapy. Patients with extrahepatic CCA (ECCA) were included as a comparison group. RESULTS: Sample pairs from 65 patients with ICCA (n = 54) and ECCA (n = 11) were analyzed. The median time between sample collection was 19.6 months (range, 2.7-122.9). For the entire cohort, the overall oncogenic concordance was 49% and the mutational concordance was 62% between primary and advanced disease samples. Subgroup analyses of ICCA and ECCA revealed overall/mutational concordance rates of 47%/58% and 60%/84%, respectively. Oncogenic concordance was similarly low for pairs exposed to systemic therapy between sample collections (n = 50, 53% overall, 68% mutational). In patients treated with targeted therapy for IDH1/2 alterations (n = 6) or FGFR2 fusions (n = 3), there was 100% concordance between the primary and advanced disease specimens. In two patients, FGFR2 (n = 1) and IDH1 (n = 1) alterations were detected de novo in the advanced disease specimens. CONCLUSION: The results reflect a high degree of heterogeneity in ICCA and argue for reassessment of the dominant driver mutations with change in disease status.

Preoperative CT and survival data for patients undergoing resection of colorectal liver metastases.

The liver is a common site for the development of metastases in colorectal cancer. Treatment selection for patients with colorectal liver metastases (CRLM) is difficult; although hepatic resection will cure a minority of CRLM patients, recurrence is common. Reliable preoperative prediction of recurrence could therefore be a valuable tool for physicians in selecting the best candidates for hepatic resection in the treatment of CRLM. It has been hypothesized that evidence for recurrence could be found via quantitative image analysis on preoperative CT imaging of the future liver remnant before resection. To investigate this hypothesis, we have collected preoperative hepatic CT scans, clinicopathologic data, and recurrence/survival data, from a large, single-institution series of patients (n = 197) who underwent hepatic resection of CRLM. For each patient, we also created segmentations of the liver, vessels, tumors, and future liver remnant. The largest of its kind, this dataset is a resource that may aid in the development of quantitative imaging biomarkers and machine learning models for the prediction of post-resection hepatic recurrence of CRLM.

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.

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.