Faculty Bibliography

BACKGROUND:The 2024 Kyoto guidelines for the management of intraductal mucinous neoplasms (IPMNs) build on previous guidelines that consider worrisome features (WF) and high-risk stigmata (HRS) to recommend surveillance or resection. These new guidelines have not yet been validated. METHODS:Patients undergoing pancreatectomy for an IPMN at an academic medical center between 2012 and 2023 were included. IPMNs were categorized as low-grade dysplasia (LGD), high-grade dysplasia (HGD), or invasive carcinoma (IC). Preoperative imaging was used to determine HRS and WF in accordance with the 2024 Kyoto guidelines. We compared IPMNs with LGD to those with HGD or IC using univariate analyses and evaluated logistic regression models with c-statistics. RESULTS:Of 211 patients, 84 (40%) had LGD, 49 (23%) had HGD, and 78 (37%) had IC. Among HRS, obstructive jaundice (p = 0.004), pancreatic duct ≥ 10 mm (p < 0.001), and suspicious or positive cytology (p < 0.001) were significantly associated with HGD/IC. An increasing number of HRS were associated with higher rates of HGD/IC. Among WFs, an abrupt change in the caliber of pancreatic duct with distal pancreatic atrophy (p = 0.001) and cystic growth ≥ 2.5 mm/year (p = 0.033) were significantly associated with higher rates of HGD/IC. Increasing numbers of WFs were also associated with higher rates of HGD/IC. The 2024 Kyoto model showed improved discrimination (area under the curve [AUC] = 0.849) compared with the 2017 Fukuoka model (AUC=0.780, p = 0.06). CONCLUSION/CONCLUSIONS:The risk of HGD/IC in IPMNs increased in a stepwise fashion as the number of WFs increased. The 2024 guidelines represent an advancement over the 2017 guidelines, notably with the inclusion of suspicious cytology as an HRS.

BACKGROUND:Intraductal papillary mucinous neoplasms (IPMNs) are precursor lesions of pancreatic cancer with highly variable malignant potential. Current understanding of their biology remains incomplete, limiting accurate risk stratification and targeted interventions. OBJECTIVE:This study aimed to characterise the molecular and immune features of IPMN across different dysplasia grades and histological subtypes, with a focus on IPMN-associated invasive carcinoma (IPMN-IC). DESIGN/METHODS:Spatial whole-transcriptome profiling using Digital Spatial Profiling was conducted on 12 patients, capturing the full histological and dysplastic spectrum of IPMN and conventional pancreatic ductal adenocarcinoma. A total of 117 epithelial, immune and stromal areas of interest were analysed. An expanded cohort of 43 patients with IPMN was used to validate selected key markers. RESULTS:Transcriptomic analysis unveiled stage-specific molecular alterations and identified two distinct subsets of high-grade (HG) IPMN lesions: one resembling indolent lesions (HG) and the other IC (HG+). Key markers associated with divergent biological behaviours were identified, including MUC5AC and TFF1 in indolent lesions, and Claudin-1 in lesions with invasive potential. Immune profiling revealed a trajectory from activation to suppression during IPMN progression. Several characteristic immune checkpoint molecules, including CEACAM1 and CD44, were identified in IPMN-IC. CONCLUSION/CONCLUSIONS:This study provides a spatially resolved molecular map of IPMN progression, delineating key transcriptomic and immune signatures. These findings advance the understanding of IPMN biology and highlight potential biomarkers for risk stratification and therapeutic strategies.

BACKGROUND:Accurate preoperative malignancy risk assessment in intraductal papillary mucinous neoplasm (IPMN) is essential to balance timely intervention for high-grade dysplasia or invasive cancer (HGD/IC) against avoiding unnecessary or premature surgery in low-grade IPMN. This study aimed to externally validate the 2023 International Association of Pancreatology (IAP)/Kyoto guidelines and develop a combined prediction model incorporating routinely collected clinical data and laboratory parameters. METHODS:We conducted a retrospective cohort study of 194 patients who underwent resection for IPMN between 2012 and 2024. We evaluated the predictive performance of the current IAP/Kyoto criteria ("Kyoto model"), developed a clinical model using routinely available laboratory and clinical variables, and integrated both into a combined model. Model performance was assessed using discrimination and calibration metrics, with internal validation via bootstrapping and five-fold cross-validation. RESULTS:The Kyoto model demonstrated modest discrimination (AUC 0.62). The clinical model, incorporating neutrophil-to-lymphocyte ratio (NLR), smoking history, blood glucose, CA19-9, and alkaline phosphatase, achieved an optimism-corrected AUC of 0.76. Compared to the Kyoto model, the combined model (AUC 0.77) significantly improved discrimination and calibration (p < 0.001). At a predicted probability threshold of >0.75, the combined model achieved a 90% specificity and 91% positive predictive value for HGD/IC, identifying a high-risk subgroup suitable for surgical intervention. CONCLUSIONS:Integrating routinely collected clinical and laboratory parameters with guideline-based imaging features shows promise to enhance preoperative identification of high-risk IPMN in patients already being considered for surgical resection. The combined model offers a practical, high-specificity tool to support surgical decision-making in this selected population, though its performance metrics should not be extrapolated to unselected surveillance cohorts. External validation is required before broader clinical implementation.

BACKGROUND:Poor outcomes in pancreatic ductal adenocarcinoma (PDAC) are associated with delayed diagnosis and early systemic spread of disease. Development of liquid biopsies for screening could help detect low-stage disease in asymptomatic patients. We aimed to evaluate the association between incidental diagnosis on outcomes and assess the potential role of liquid biopsies. STUDY DESIGN/METHODS:An institutional registry was used to identify patients undergoing resection for PDAC at between 2010 and 2015. Patients were stratified based on presenting symptoms, and outcomes were analyzed. Preoperatively collected plasma that was available on these patients was analyzed using a multianalyte screening test based on ctDNA and proteins. RESULTS:Seventy-nine (9.6%) of 823 patients were diagnosed incidentally (asymptomatic at diagnosis). Incidental diagnosis was associated with type of surgery, and absence of nodal disease and lymphovascular invasion (all P<0.05). On multivariable analysis incidental diagnosis (HR, 0.561; 95%CI, 0.406-0.775; P<0.001) was independently associated with improved overall survival (OS), while tumor size ≥4cm (HR, 1.617; 95%CI, 1.201-2.176; P=0.002), nodal disease (HR, 1.259; 95%CI, 1.018-1.558; P=0.034), perineural invasion (HR,1.338; 95%CI, 1.030-1.739; P=0.029), and positive margins (HR,1.302; 95%CI, 1.058-1.602; P=0.013) were associated with poorer OS. Asymptomatic patients had a significantly longer OS (median-OS: 38 vs. 19 months (P<0.001). The rate of multianalyte test positivity was 75% (6/8) in asymptomatic patients compared to 73% (59/81) in symptomatic patients (P=0.895). CONCLUSION/CONCLUSIONS:Approximately 10% of patients with PDAC are diagnosed incidentally. In resected PDAC, incidental diagnosis is independently associated with improved OS. Multianalyte screening tests perform equally well in asymptomatic and symptomatic patients. These findings further reinforce the need for development of screening tools that can increase the rate of diagnosis at an asymptomatic stage and improve survival.

Currently, no consensus exists regarding the definition of oligometastatic pancreatic ductal adenocarcinoma, its necessary diagnostic measures, and potential treatment approaches. To address these knowledge gaps, the OligoPanc project brought together an interdisciplinary group of experts to establish consensus using a modified Delphi process and clinical vignettes. Participants agreed that the number of metastatic lesions and the number of affected organs are key elements in defining oligometastatic pancreatic ductal adenocarcinoma. Specifically, up to three lesions in a single organ, either the liver or the lung, define oligometastatic pancreatic ductal adenocarcinoma and could be either synchronous or metachronous. Necessary diagnostics include a triple-phase contrast-enhanced CT scan of the chest and abdomen and MRI of the liver with a hepatocyte-specific contrast agent. In unclear cases, [¹⁸F]fluorodeoxyglucose-PET CT or MRI can be considered. A multidisciplinary tumour board is essential. Patient-intrinsic factors, including age, do not define oligometastatic disease but should be considered for any treatment decision. Systemic treatment before any local consolidative treatment, including surgery, stereotactic ablative radiotherapy, or other locally ablative techniques, is mandatory. The proposed definition should be incorporated into future trials to improve comparability and enable validation.

OBJECTIVE:The International Study Group of Pancreatic Surgery (ISGPS) aimed to uniform the definition and classification of mortality following pancreatic resections, to guide strategies for reducing preventable deaths and standardize reporting. BACKGROUND:Reported rates of mortality after pancreatic surgery vary widely depending on patient comorbidities, case mix, and institutional expertise and resources. Conventional reporting lacks granularity and fails to capture the mechanisms leading to death. A standardized classification rooted in causal analysis may provide a more meaningful framework to appraise outcomes and design targeted interventions. METHODS:A systematic review of the literature, focusing on mortality rates, causes of death, and existing classification systems after pancreatectomy was conducted. A consensus definition and tripartite classification were developed through iterative discussions, revisions, and final approval by the ISGPS board members. RESULTS:Postpancreatectomy mortality (PPM) was defined as death occurring within 90 days of any pancreatic resection, directly or indirectly attributable to a surgical complication and retrospectively linked to it through root-cause analysis. Three categories were established: PPM 1, vascular/technical complexity-related mortality (15-30%); PPM 2, pancreatectomy-specific complication-related deaths, mainly due to postoperative pancreatic fistula (POPF) and secondary systemic deterioration (45-65%); and PPM 3, cardiopulmonary and cerebrovascular deaths (10-25%). Each category reflects distinct mechanisms, timing of onset, intervention windows, and opportunities for rescue. DISCUSSION/CONCLUSIONS:The proposed ISGPS classification of mortality enables the development of targeted strategies to reduce potentially preventable deaths and provides a more robust framework for the appraisal and benchmarking of surgical outcomes. Prospective validation is warranted to standardize this newly defined quality metric, ensuring its consistent use in future reporting and ultimately enhancing surgical quality and patient safety on a global scale.

OBJECTIVE:We aimed to better understand patients' treatment preferences and quantify the level of cancer risk at which treatment preferences change (risk threshold) to inform better counseling of patients with intraductal papillary mucinous neoplasms (IPMNs). SUMMARY BACKGROUND DATA/BACKGROUND:The complexity of IPMN management provides an opportunity to align treatment with individual preference. METHODS:We surveyed a sample of healthy volunteers simulating a common scenario: undergoing an imaging study that incidentally identifies an IPMN. In the scenario, the estimated risk of cancer in the IPMN was 5%. Patients were asked their treatment preference (surgery or surveillance), to quantify the level of cancer risk in the IPMN at which their treatment preference would change (i.e. risk threshold), and their level of cancer anxiety as measured on a 5-point Likert scale. We examined associations between participant characteristics, treatment preferences, and risk threshold using multivariable linear regression. RESULTS:The median risk threshold among the 520 participants was 25% (IQR 2.3-50%). The risk threshold had a bimodal distribution: 40% of participants had a risk threshold between 0-10% and 47% had a risk threshold above 30%. When informed that the risk of cancer was 5%, 62% of participants (n=323) preferred surveillance, and the remaining 38% (n=197) preferred surgery. After adjusting for potential confounders, participants who expressed "worry" or "extreme worry" about the malignancy risk of IPMN had significantly lower risk thresholds than participants who were "not at all worried" (Coefficient -12, 95%CI -21 to -2, P=0.015 and Coefficient -18, 95%CI -29 to -8, P<0.001, respectively). CONCLUSIONS:Participants varied in treatment preference and risk threshold of incidentally identified IPMNs. Given the uncertainty in estimating the true malignant potential of IPMNs, a better understanding of a patient's risk threshold, as influenced by patient concern about malignancy, will help inform the shared decision-making process.

BACKGROUND/PURPOSE/OBJECTIVE:Intraductal papillary mucinous neoplasms (IPMNs) progress from low-grade dysplasia to high-grade dysplasia (HGD) or invasive carcinoma (IC). High diagnostic accuracy is critical for surgical decision-making. METHODS:We searched Medline, Embase, and Cochrane Library from January 1, 2015, to January 27, 2025. Eligible studies reported on resected IPMNs, assessing diagnostic features for HGD/IC. Two reviewers screened articles, extracted data, and assessed bias using the Newcastle-Ottawa scale. Descriptive statistics summarized outcomes. The performance of worrisome features (WFs) and high-risk stigmata (HRS) based on International Association of Pancreatology guidelines were evaluated. RESULTS:In the 53 studies, 12 953 patients were included. HRS including obstructive jaundice and enhancing mural nodules ≥5mm showed robust specificity for HGD/IC, while main pancreatic duct size ≥10mm showed variable diagnostic accuracy. WFs such as cyst size ≥3 cm performed poorly, while cyst growth rate >3.5 mm/year demonstrated higher sensitivity (88%) and specificity (91%). Although rare, abrupt caliber change with distal atrophy was a robust predictor of malignancy (median odds ratio: 3.01). Acute pancreatitis and lymphadenopathy displayed variable value. Incremental improvement in diagnostic accuracy was observed with additional HRS or WFs. CONCLUSIONS:Current diagnostic markers are valuable but provide limited guidance for surgical decision-making in IPMNs, highlighting the need for further refinement of diagnostic tools.