Comprehensive characterization of intraductal oncocytic papillary neoplasm (IOPN) of the pancreas: a systematic and critical review.

Intraductal oncocytic papillary neoplasm (IOPN) of the pancreas is a recently recognized pancreatic tumor. Here, we aimed to determine the most essential features with the systematic review tool. PubMed, SCOPUS, and Embase were searched for studies reporting data on pancreatic IOPN. The clinicopathological, immunohistochemical, and molecular data were extracted and summarized. Then, a comparative analysis of the molecular alterations of IOPN with those of pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasm from reference cohorts (including The Cancer Genome Atlas) was conducted. The key findings from 414 IOPNs were as follows: 1) Clinicopathological Features: Male-to-female ratio was 1,5:1. Pancreatic head was the most common site (131/237, 55.3%), but a diffuse tumor extension involving more than one pancreatic segment was described in about 1/5 of cases (49/237, 20.6%). The mean size was 45.5 mm. An associated invasive carcinoma was present in 50% of cases (168/336). In those cases, most tumors were pT1/pT2 and pN0 (>80%), and vascular invasion was uncommon (20.6%). Regarding survival, more than 90% of patients were alive after surgical resection. 2) Immunohistochemical and Molecular Features: The most expressed mucins were MUC5AC (110/112, 98.2%) and MUC6 (78/84, 92.8%). Compared with pancreatic ductal adenocarcinoma and intraductal papillary mucinous neoplasm, the classic pancreatic drivers KRAS, TP53, CDKN2A, SMAD4, and GNAS were less altered in IOPN (p<0.01). Moreover, fusions involving PRKACA or PRKACB genes were detected in all of 68 cases examined, with PRKACB::ATP1B1 as the most common (27/68 cases, 39.7%). These genomic events emerged as an entity-defining molecular alteration of IOPN (p<0.01). Thus, such fusions represent a promising biomarker for diagnostic purposes. Recent evidence also suggests their role in influencing the acquisition of oncocytic morphology. IOPN is a distinct pancreatic neoplasm with specific clinicopathological and molecular features. Considering the clinical/prognostic implications, its recognition is essential for pathologists and, ultimately, patients' management.

Who Do We Fail to Rescue after Pancreatoduodenectomy? Outcomes Among >4000 Procedures Expose Windows of Opportunity.

OBJECTIVE: Our investigation on in-hospital mortality after 4474 pancreatoduodenectomies aimed to identify time-dependent risks as well as windows of opportunity to rescue patients from complications. BACKGROUND: Pancreatoduodenectomy is generally considered a safe procedure with a 1-10% perioperative mortality based on complexity and surgical volume. Yet, patients are susceptible for life-threatening complications particularly with extended resections. Recognition of distinct vulnerabilities over time while patients recover is required to permit focused monitoring, sophisticated resource allocation, and greatest surgical safety. METHODS: Patients who deceased in-hospital after pancreatoduodenectomy between 2003-2021 were retrieved from the institutional pancreatectomy registry and analyzed in detail with respect to their postoperative course. RESULTS: Among 4474 pancreatoduodenectomies, 156 patients deceased in-hospital (3.5%). When assessing root causes of mortality, we observed 3 different clusters of complications which were postpancreatectomy-specific (47.4%), visceral vasculature-associated (25.6%), or cardiopulmonary in origin (23.7%). The median times of root cause onset in the 3 categories were postoperative day (POD) 9, POD 4.5 ( P =0.008) and POD 3 ( P <0.001), and medians of in-hospital mortality were POD 31, POD 18 ( P =0.009) and POD 8 ( P <0.001), respectively. Intervals between root cause onset and mortality varied with medians of 23 days, 11 days ( P =0.017), and 1 days ( P <0.001). The 3 categories were similarly distributed between different types of surgical complexity. CONCLUSION: Postpancreatectomy-specific complications prompt almost half of in-hospital mortalities after pancreatoduodenectomy, with rather long intervals for interventions to prevent failure to rescue. In contrast, visceral vasculature-related events and cardiopulmonary complications dominate early in-hospital mortalities with short intervals until mortality, demanding rigorous management of such events or preoperative conditioning. These data externally validate a previous high-volume initiative and highlight distinct windows of opportunity to optimize perioperative safety.

Association of Smoking with progression from low-risk to high-risk intraductal papillary mucinous neoplasms and pancreatic cancer.

BACKGROUND: Factors associated with the risk of pancreatic adenocarcinoma (PDAC) may play a role in the development and progression of Intraductal Papillary Mucinous Neoplasms (IPMNs). However, data are limited. AIM: To compare exposome factors in three groups of patients with "high or low-risk" IPMNs, as assessed at diagnosis and during a 24-months follow-up, and with PDAC. METHODS: Patients were matched (same sex, age ±5) 1:1. Exposure variables were compared across groups using Kruskal-Wallis, ANOVA, or Chi-square tests with Bonferroni correction. RESULTS: A total of 151 patients were enrolled in each of the three groups (453 overall). The proportion of current smokers was progressively higher in "low-risk", "high-risk" IPMNs and PDAC patients (8.1 %, 11.2 %, 23.3 %; p = 0.0002). The three groups did not differ in terms of ever or heavy smoking, BMI, history of diabetes, cancer, cholecystectomy or chronic pancreatitis, use of statins or aspirin, and family history of cancer. A history of peptic ulcer was more common in PDAC (7.2 %) than in either "low-risk" (2.0 %) or "high-risk" (2.6%) IPMNs (p = 0.02, not significant after Bonferroni correction). CONCLUSION: Active smoking seems associated with the progression of IPMNs to malignancy, and cessation of active smoking might be advised in patients with IPMN.

Thirty-day prevalence and clinical impact of fluid collections at the resection margin after distal pancreatectomy: Follow-up of a multicentric randomized controlled trial.

BACKGROUND: Postoperative fluid collections at the resection margin of the pancreatic stump are frequent after distal pancreatectomy, yet their clinical impact is unclear. The aim of this study was to assess the 30-day prevalence of postoperative fluid collections after distal pancreatectomy and the factors associated with a clinically relevant condition. METHODS: Patients enrolled in a randomized controlled trial of parenchymal transection with either reinforced, triple-row staple, or ultrasonic dissector underwent routine magnetic resonance 30 days postoperatively. Postoperative fluid collection was defined as a cyst-like lesion of at least 1 cm at the pancreatic resection margin. Postoperative fluid collections requiring any therapy were defined as clinically relevant. RESULTS: A total of 133 patients were analyzed; 69 were in the triple-row staple transection arm, and 64 were in the ultrasonic dissector transection arm. The overall 30-day prevalence of postoperative fluid collections was 68% (n = 90), without any significant difference between the two trial arms. Postoperative serum hyperamylasemia was more frequent in patients with postoperative fluid collections than those without (31% vs 7%, P = .001). Among the postoperative fluid collection population, an early postoperative pancreatic fistula (odds ratio 14.9, P = .002), post pancreatectomy acute pancreatitis (odds ratio 12.7, P = .036), and postoperative fluid collection size larger than 50 mm (odds ratio 6.6, P = .046) were independently associated with a clinically relevant postoperative fluid collection. CONCLUSION: Postoperative fluid collections at the resection margin are common after distal pancreatectomy and can be predicted by early assessment of postoperative serum hyperamylasemia. A preceding pancreatectomy acute pancreatitis and/or postoperative pancreatic fistula and large collections (>50 mm) were associated with a clinically relevant postoperative fluid collection, representing targets for closer follow-up or earlier therapeutic interventions.

Implications of pregnancy on MCN of the pancreas: A multicentric case-control study.

BACKGROUND: Mucinous cystic neoplasms (MCN) of the pancreas express estrogen and progesterone receptors. Several case reports describe MCN increasing in size during gestation. The aim of this study is to assess if pregnancy is a risk factor for malignant degeneration of MCN. METHODS: All female patients who underwent pancreatic resection of a MCN between 2011 and 2021 were included. MCN resected or diagnosed within 12 months of gestation were defined perigestational. MCN with high grade dysplasia or an invasive component were classified in the high grade (HG) group. The primary outcome was defined as the correlation between exposure to gestation and peri-gestational MCN to development of HG-MCN. RESULTS: The study includes 176 patients, 25 (14 %) forming the HG group, and 151 (86 %) forming the low grade (LG) group. LG and HG groups had a similar distribution of systemic contraceptives use (26 % vs. 16 %, p = 0.262), and perigestational MCN (7 % vs 16 %, p = 0.108). At univariate analysis cyst size ≥10 cm (OR 5.3, p < 0.001) was associated to HG degeneration. Peri gestational MCN positively correlated with cyst size (R = 0.18, p = 0.020). In the subgroup of 14 perigestational MCN patients 29 % had HG-MCN and 71 % experienced cyst growth during gestation with an average growth of 55.1 ± 18 mm. CONCLUSIONS: Perigestational MCN are associated to increased cyst diameter, and in the subset of patients affected by MCN during gestation a high rate of growth was observed. Patients with a MCN and pregnancy desire should undergo multidisciplinary counselling.

A machine learning predictive model for recurrence of resected distal cholangiocarcinoma: Development and validation of predictive model using artificial intelligence.

INTRODUCTION: Distal Cholangiocarcinoma (dCCA) represents a challenge in hepatobiliary oncology, that requires nuanced post-resection prognostic modeling. Conventional staging criteria may oversimplify dCCA complexities, prompting the exploration of novel prognostic factors and methodologies, including machine learning algorithms. This study aims to develop a machine learning predictive model for recurrence after resected dCCA. MATERIAL AND METHODS: This retrospective multicentric observational study included patients with dCCA from 13 international centers who underwent curative pancreaticoduodenectomy (PD). A LASSO-regularized Cox regression model was used to feature selection, examine the path of the coefficient and create a model to predict recurrence. Internal and external validation and model performance were assessed using the C-index score. Additionally, a web application was developed to enhance the clinical use of the algorithm. RESULTS: Among 654 patients, LNR (Lymph Node Ratio) 15, neural invasion, N stage, surgical radicality, and differentiation grade emerged as significant predictors of disease-free survival (DFS). The model showed the best discrimination capacity with a C-index value of 0.8 (CI 95 %, 0.77%-0.86 %) and highlighted LNR15 as the most influential factor. Internal and external validations showed the model's robustness and discriminative ability with an Area Under the Curve of 92.4 % (95 % CI, 88.2%-94.4 %) and 91.5 % (95 % CI, 88.4%-93.5 %), respectively. The predictive model is available at https://imim.shinyapps.io/LassoCholangioca/. CONCLUSIONS: This study pioneers the integration of machine learning into prognostic modeling for dCCA, yielding a robust predictive model for DFS following PD. The tool can provide information to both patients and healthcare providers, enhancing tailored treatments and follow-up.

Magnetic resonance imaging short protocols for intraductal papillary mucinous neoplasm (IPMN) surveillance: The time has come.

BACKGROUND/OBJECTIVES: To analyze the diagnostic performance of three short magnetic resonance imaging (MRI) protocols for the follow-up of pancratic intraductal papillary mucinous neoplasms (IPMN). METHODS: Follow-up MRI examinations of 287 patients with IPMN performed in two centers were retrospectively retrieved. Four MRI protocols were identified as follows: T1-weighted (T1w), T2-weighted (T2w), and MRCP sequences (protocol 1); T1w, T2w, MRCP, and diffusion-weighted (DWI) sequences (protocol 2); T1w, T2w, MRCP, and post-contrast T1w-sequences (protocol 3); and a comprehensive protocol including all previous sequences (protocol 4). Three radiologists with different experience in abdominal imaging expressed their opinion upon the optimal patient's management upon the evaluation of each protocol. Intra-and inter-observer agreement and concordance with the clinical decision expressed by a pancreatic surgeon were calculated with Cohen's kappa test. RESULTS: 223 patients were included (66±10 years; 92 men, 131 women). 143 patients had branch-duct-IPMNs, 25 main-duct-IPMNs and 55 mixed-type-IPMNs. 79 patients underwent surgery, resulting in 52 high-grade dysplasia (HGD) and 27 low-grade dysplasia (LGD). Concordance for the expert reader between protocols 1, 2 and 3 and the actual clinical decision were 0.63, 0.72, and 0.74 respectively (95% CI, 0.53-0.73, 0.63-0.81, and 0.65-0.83). Inter-observer agreement between reader 1 and reader 2, reader 1 and reader 3, and reader 2 and reader 3 were: 0.71, 0.50, and 0.75 for protocol 1 (95% CI, 0.63-0.81, 0.40-0.60, and 0.66-0.84);0.68, 0.54, and 0.84 for protocol 2 (95% CI, 0.59-0.77, 0.44-0.64, and 0.76-0.91); and 0.77, 0.65, and 0.86 for protocol 3 (95% CI, 0.69-0.86, 0.55-0.74, and 0.80-0.93). CONCLUSIONS: Short MRI protocol is suitable for IPMN surveillance.

REDISCOVER guidelines for borderline-resectable and locally advanced pancreatic cancer: management algorithm, unanswered questions, and future perspectives.

The REDISCOVER guidelines present 34 recommendations for the selection and perioperative care of borderline-resectable (BR-PDAC) and locally advanced ductal adenocarcinoma of the pancreas (LA-PDAC). These guidelines represent a significant shift from previous approaches, prioritizing tumor biology over anatomical features as the primary indication for resection. Condensed herein, they provide a practical management algorithm for clinical practice. However, the guidelines also highlight the need to redefine LA-PDAC to align with modern treatment strategies and to solve some contradictions within the current definition, such as grouping "difficult" and "impossible" to resect tumors together. Furthermore, the REDISCOVER guidelines highlight several areas requiring urgent research. These include the resection of the superior mesenteric artery, the management strategies for patients with LA-PDAC who are fit for surgery but unable to receive multi-agent neoadjuvant chemotherapy, the approach to patients with LA-PDAC who are fit for surgery but demonstrate high serum Ca 19.9 levels even after neoadjuvant treatment, and the optimal timing and number of chemotherapy cycles prior to surgery. Additionally, the role of primary chemoradiotherapy versus chemotherapy alone in LA-PDAC, the timing of surgical resection post-neoadjuvant/primary chemoradiotherapy, the efficacy of ablation therapies, and the management of oligometastasis in patients with LA-PDAC warrant investigation. Given the limited evidence for many issues, refining existing management strategies is imperative. The establishment of the REDISCOVER registry ( https://rediscover.unipi.it/ ) offers promise of a unified research platform to advance understanding and improve the management of BR-PDAC and LA-PDAC.

Impact of age, comorbidities and relevant changes on surveillance strategy of intraductal papillary mucinous neoplasms: a competing risk analysis.

OBJECTIVE: Cost-effectiveness of surveillance for branch-duct intraductal papillary mucinous neoplasms (BD-IPMNs) is debated. We combined different categories of risks of IPMN progression and of IPMN-unrelated mortality to improve surveillance strategies. DESIGN: Retrospective analysis of 926 presumed BD-IPMNs lacking worrisome features (WFs)/high-risk stigmata (HRS) under surveillance. Charlson Comorbidity Index (CACI) defined the severity of comorbidities. IPMN relevant changes included development of WF/HRS, pancreatectomy or death for IPMN or pancreatic cancer. Pancreatic malignancy-unrelated death was recorded. Cumulative incidence of IPMN relevant changes were estimated using the competing risk approach. RESULTS: 5-year cumulative incidence of relevant changes was 17.83% and 1.6% developed pancreatic malignancy. 5-year cumulative incidences for IPMN relevant changes were 13.73%, 19.93% and 25.04% in low-risk, intermediate-risk and high-risk groups, respectively. Age ≥75 (HR: 4.15) and CACI >3 (HR: 3.61) were independent predictors of pancreatic malignancy-unrelated death. 5-year cumulative incidence for death for other causes was 15.93% for age ≥75+CACI >3 group and 1.49% for age <75+CACI ≤3. 5-year cumulative incidence of IPMN relevant changes were 13.94% in patients with age <75+CACI ≤3 compared with 29.60% in those with age ≥75+CACI >3. In this group 5-year rate of malignancy-free patients was 95.56% with a 5-year survival of 79.51%. CONCLUSION: Although it is not uncommon the occurrence of changes considered by current guidelines as relevant during surveillance of low risk BD-IPMNs, malignancy rate is low and survival is significantly affected by competing patients' age and comorbidities. IPMN surveillance strategy should be tailored based on these features and modulated over time.

Prophylactic abdominal drainage after distal pancreatectomy (PANDORINA): an international, multicentre, open-label, randomised controlled, non-inferiority trial.

BACKGROUND: Prophylactic passive abdominal drainage is standard practice after distal pancreatectomy. This approach aims to mitigate the consequences of postoperative pancreatic fistula (POPF) but its added value, especially in patients at low risk of POPF, is currently being debated. We aimed to assess the non-inferiority of a no-drain policy in patients after distal pancreatectomy. METHODS: In this international, multicentre, open-label, randomised controlled, non-inferiority trial, we recruited patients aged 18 years or older undergoing open or minimally invasive elective distal pancreatectomy for all indications in 12 centres in the Netherlands and Italy. We excluded patients with an American Society of Anesthesiology (ASA) physical status of 4-5 or WHO performance status of 3-4, added by amendment following the death of a patient with ASA 4 due to a pre-existing cardiac condition. Patients were randomly assigned (1:1) intraoperatively by permuted blocks (size four to eight) to either no drain or prophylactic passive drain placement, stratified by annual centre volume (<40 or ≥40 distal pancreatectomies) and low risk or high risk of grade B or C POPF. High-risk was defined as a pancreatic duct of more than 3 mm in diameter, a pancreatic thickness at the neck of more than 19 mm, or both, based on the Distal Pancreatectomy Fistula Risk Score. Other patients were considered low-risk. The primary outcome was the rate of major morbidity (Clavien-Dindo score ≥III), and the most relevant secondary outcome was grade B or C POPF, grading per the International Study Group for Pancreatic Surgery. Outcomes were assessed up to 90 days postoperatively and analysed in the intention-to-treat population and per-protocol population, which only included patients who received the allocated treatment. A prespecified non-inferiority margin of 8% was compared with the upper limit of the two-sided 95% CI (Wald) of unadjusted risk difference to assess non-inferiority. This trial is closed and registered in the Netherlands Trial Registry, NL9116. FINDINGS: Between Oct 3, 2020, and April 28, 2023, 376 patients were screened for eligibility and 282 patients were randomly assigned to the no-drain group (n=138; 75 [54%] women and 63 [46%] men) or the drain group (n=144; 73 [51%] women and 71 [49%] men). Seven patients in the no-drain group received a drain intraoperatively; consequently, the per-protocol population included 131 patients in the no-drain group and 144 patients in the drain group. The rate of major morbidity was non-inferior in the no-drain group compared with the drain group in the intention-to-treat analysis (21 [15%] vs 29 [20%]; risk difference -4·9 percentage points [95% CI -13·8 to 4·0]; pnon-inferiority=0·0022) and the per-protocol analysis (21 [16%] vs 29 [20%]; risk difference -4·1 percentage points [-13·2 to 5·0]; pnon-inferiority=0·0045). Grade B or C POPF was observed in 16 (12%) patients in the no-drain group and in 39 (27%) patients in the drain group (risk difference -15·5 percentage points [95% CI -24·5 to -6·5]; pnon-inferiority<0·0001) in the intention-to-treat analysis. Three patients in the no-drain group died within 90 days; the cause of death in two was not considered related to the trial. The third death was a patient with an ASA score of 4 who died after sepsis and a watershed cerebral infarction at second admission, leading to multiple organ failure. No patients in the drain group died within 90 days. INTERPRETATION: A no-drain policy is safe in terms of major morbidity and reduced the detection of grade B or C POPF, and should be the new standard approach in eligible patients undergoing distal pancreatectomy. FUNDING: Ethicon UK (Johnson & Johnson Medical, Edinburgh, UK).

Systematic review on surveillance for non-resected branch-duct intraductal papillary mucinous neoplasms of the pancreas.

BACKGROUND: The management of branch-duct type intraductal papillary mucinous neoplasms (BD-IPMN) varies in existing guidelines. This study investigated the optimal surveillance protocol and safe discontinuation of surveillance considering natural history in non-resected IPMN, by systematically reviewing the published literature. METHODS: This review was guided by PRISMA. Research questions were framed in PICO format "CQ1-1: Is size criteria helpful to determine surveillance period? CQ1-2: How often should surveillance be carried out? CQ1-3: When should surveillance be discontinued? CQ1-4: Is nomogram predicting malignancy useful during surveillance?". PubMed was searched from January-April 2022. RESULTS: The search generated 2373 citations. After screening, 83 articles were included. Among them, 33 studies were identified for CQ1-1, 19 for CQ1-2, 26 for CQ1-3 and 12 for CQ1-4. Cysts <1.5 or 2 cm without worrisome features (WF) were described as more indolent, and most studies advised an initial period of surveillance. The median growth rate of cysts <2 cm ranged from 0.23 to 0.6 mm/year. Patients with cysts <2 cm showing no morphological changes and no WF after 5-years of surveillance have minimal malignancy risk of 0-2%. Two nomograms created with over 1000 patients had AUCs of around 0.8 and appear to be feasible in a real-world practice. CONCLUSIONS: For patients with suspected BD-IPMN <2 cm and no other WF, less frequent surveillance is recommended. Surveillance may be discontinued for cysts that remain stable during 5-year surveillance, with consideration of patient condition and life expectancy. With this updated surveillance strategy, patients with non-worrisome BD-IPMN should expect more streamlined management and decreased healthcare utilization.

Postoperative Hyperamylasemia (POH) is an Early Predictor of Pancreatic Fistula Occurrence and Severity after Distal Pancreatectomy: Results from a European Multicentric Study.

OBJECTIVES: The aim of this international multicentric study is to characterize postoperative hyperamylasemia (POH) after distal pancreatectomy (DP), with particular focus on its relationship with postoperative pancreatic fistula (POPF) occurrence and severity. BACKGROUND: The clinical relevance of POH after DP and its relationship with the occurrence and severity of POPF have not been explored yet. METHODS: All patients undergoing DP for any indication between 2015 and 2021 at three European referral Centers for pancreatic surgery were retrospectively analyzed. Drain fluid amylase (DFA), C-reactive protein (C-RP), and serum amylase were examined from postoperative-day (POD) 1 to 3. Biochemical leak (BL), POPF, POH, and post-pancreatectomy hemorrhage (PPH) were defined and graded according to ISGPS definitions. RESULTS: In total 1192 patients were included. Overall rates of POH and POPF were 18% (n= 210) and 29% (n= 344), respectively. The presence of DFA ≥2000 U/L on POD 1 (OR=2.11, 95% CI 1.68-2.86), C-RP ≥200 mg/L on POD 3 (OR=2.19, 95% CI 1.68-2.86), and POH (OR=1.58, 95% CI 1.14-2.19) were all independent early predictors of POPF (all P< 0.01). The presence of POH almost doubled the rate of POPF (43% vs. 26%, P<0.001), and higher POPF severity presented also higher POH rates (no POPF= 12%; BL= 19%; B POPF= 24%; C POPF= 52%). Among patients developing POPF, patients with POH had higher rates of PPH (22% vs 9%, P= 0.001), sepsis (24% vs 13%; P=0.011), re-operation (21% vs 8%; P< 0.01), and mortality (3% vs 0.3%; P= 0.025). CONCLUSIONS: The occurrence of POH is an early predictor of POPF and its severity after DP. The diagnosis of POH might define patients at higher risk for a complicated course, targeting them for prevention / mitigation strategies against pancreas specific complications.

REDISCOVER International Guidelines on the Perioperative Care of Surgical Patients With Borderline-resectable and Locally Advanced Pancreatic Cancer.

OBJECTIVE: The REDISCOVER consensus conference aimed at developing and validating guidelines on the perioperative care of patients with borderline-resectable (BR-) and locally advanced (LA) pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Coupled with improvements in chemotherapy and radiation, the contemporary approach to pancreatic surgery supports the resection of BR-PDAC and, to a lesser extent, LA-PDAC. Guidelines outlining the selection and perioperative care for these patients are lacking. METHODS: The Scottish Intercollegiate Guidelines Network (SIGN) methodology was used to develop the REDISCOVER guidelines and create recommendations. The Delphi approach was used to reach a consensus (agreement ≥80%) among experts. Recommendations were approved after a debate and vote among international experts in pancreatic surgery and pancreatic cancer management. A Validation Committee used the AGREE II-GRS tool to assess the methodological quality of the guidelines. Moreover, an independent multidisciplinary advisory group revised the statements to ensure adherence to nonsurgical guidelines. RESULTS: Overall, 34 recommendations were created targeting centralization, training, staging, patient selection for surgery, possibility of surgery in uncommon scenarios, timing of surgery, avoidance of vascular reconstruction, details of vascular resection/reconstruction, arterial divestment, frozen section histology of perivascular tissue, extent of lymphadenectomy, anticoagulation prophylaxis, and role of minimally invasive surgery. The level of evidence was however low for 29 of 34 clinical questions. Participants agreed that the most conducive means to promptly advance our understanding in this field is to establish an international registry addressing this patient population ( https://rediscover.unipi.it/ ). CONCLUSIONS: The REDISCOVER guidelines provide clinical recommendations pertaining to pancreatectomy with vascular resection for patients with BR-PDAC and LA-PDAC, and serve as the basis of a new international registry for this patient population.

Liver resection versus radiofrequency ablation or trans-arterial chemoembolization for early-stage (BCLC A) oligo-nodular hepatocellular carcinoma: meta-analysis.

BACKGROUND: The 2022 Barcelona Clinic Liver Cancer (BCLC) algorithm does not recommend liver resection (LR) in BCLC A patients with oligo-nodular (two or three nodules ≤3 cm) hepatocellular carcinoma (HCC). This sharply contrasts with the therapeutic hierarchy concept, implying a precise treatment order exists within each BCLC stage. This study aimed to compare the outcomes of LR versus radiofrequency ablation (RFA) or trans-arterial chemoembolization (TACE) in BCLC A patients. METHODS: A meta-analysis adhering to PRISMA guidelines and the Cochrane Handbook was performed. All RCT, cohort and case-control studies that compared LR versus RFA or TACE in oligo-nodular BCLC A HCC published between January 2000 and October 2023 were comprehensively searched on PubMed, Embase, the Cochrane Library and China Biology Medicine databases. Primary outcomes were overall survival (OS) and disease-free survival (DFS) at 3 and 5 years. Risk ratio (RR) was computed as a measure of treatment effect (OS and DFS benefit) to calculate common and random effects estimates for meta-analyses with binary outcome data. RESULTS: 2601 patients from 14 included studies were analysed (LR = 1227, RFA = 686, TACE = 688). There was a significant 3- and 5-year OS benefit of LR over TACE (RR = 0.55, 95% c.i. 0.44 to 0.69, P < 0.001 and RR 0.57, 95% c.i. 0.36 to 0.90, P = 0.030, respectively), while there was no significant 3- and 5-year OS benefit of LR over RFA (RR = 0.78, 95% c.i. 0.37 to 1.62, P = 0.452 and RR 0.74, 95% c.i. 0.50 to 1.09, P = 0.103, respectively). However, a significant 3- and 5-year DFS benefit of LR over RFA was found (RR = 0.70, 95% c.i. 0.54 to 0.93, P = 0.020 and RR 0.82, 95% c.i. 0.72 to 0.95, P = 0.015, respectively). A single study comparing LR and TACE regarding DFS showed a significant superiority of LR. The Newcastle-Ottawa Scale quality of studies was high in eight (57%) and moderate in six (43%). CONCLUSIONS: In BCLC A oligo-nodular HCC patients, LR should be preferred to RFA or TACE (therapeutic hierarchy concept). Additional comparative cohort studies are urgently needed to increase the certainty of this evidence.