Faculty Bibliography

OBJECTIVE:To investigate whether tangential versus segmental portomesenteric venous resection (PVR) impacts surgical and oncological outcome in patients undergoing pancreatoduodenectomy for pancreatic cancer with portomesenteric vein (PMV) involvement. SUMMARY BACKGROUND DATA/BACKGROUND:Current comparative studies on tangential versus segmental PVR as part of pancreatoduodenectomy for pancreatic cancer include all degrees of PMV involvement, including cases where tangential PVR may not be a feasible approach, limiting the clinical applicability. METHODS:International retrospective study in 10 centers from 5 countries, including all consecutive patients after pancreatoduodenectomy with PVR for pancreatic cancer with ≤180° PMV involvement on cross-sectional imaging at diagnosis (2014-2020). Cox and logistic regression analyses were performed to investigate the association of tangential versus segmental PVR with overall survival (OS) from surgery, recurrence-free survival (RFS), locoregional recurrence, and in-hospital/30-day major morbidity, adjusting for potential confounders. RESULTS:Overall, 357 patients who underwent pancreatoduodenectomy with PVR were included (42% tangential PVR, 58% segmental PVR). The adjusted risk for in-hospital/30-day major morbidity was 23% (95%CI, 17-32) after tangential and 23% (95%CI, 17-30) after segmental PVR (P=0.98). After adjusting for confounders, PVR type was not associated with OS (HR=0.94 [95%CI, 0.69-1.30]), RFS (HR=0.94 [95% CI, 0.69 to 1.28), and locoregional recurrence (OR=0.76 [95%CI, 0.40-1.46]). CONCLUSIONS:In patients undergoing pancreatoduodenectomy for pancreatic cancer with ≤180° PMV involvement, the type of PVR (i.e., tangential vs. segmental) was not associated with differences in surgical and oncological outcome. This suggest that if both procedures are technically feasible, surgeons can choose the type of PVR based on their preference.

BACKGROUND:To improve outcomes for patients with pancreatic ductal adenocarcinoma, a complete resection is crucial. However, evidence regarding the impact of microscopically positive surgical margins (R1) on recurrence is conflicting due to varying definitions and limited populations of patients with borderline-resectable and locally advanced pancreatic cancer. Therefore, we aimed to determine the impact of the resection margin status on recurrence and survival in patients with pancreatic ductal adenocarcinoma stratified by local tumor stage. METHODS:We performed a retrospective cohort study on patients with nonmetastatic pancreatic ductal adenocarcinoma undergoing pancreatectomy at a high-volume academic center (2012-2022). R1 was subclassified into microscopic invasion of the margin (R1 direct) or carcinoma present within 1 mm but not directly involving the margin (R1 <1 mm). Overall survival and time to recurrence were assessed by log-rank test and multivariable Cox regression. RESULTS:Of 472 included patients, 154 (33%) had an R1 resection. Of those 50 (32%) had R1 <1 mm and 104 (68%) R1 direct. The most commonly involved margin was the uncinate (41%) followed by the pancreatic neck (16%) and vascular margins (9%). Overall, a stepwise shortening of time to recurrence and overall survival was observed with an increasing degree of margin involvement (median time to recurrence: R0 39.3 months, R1 <1 mm 16.0 months, and R1 direct 13.4 months, all comparisons P < .05). Multivariable analyses confirmed the independent prognostic value of R1 direct across all surgical stages. CONCLUSION/CONCLUSIONS:The resection margin status portends an independent prognostic value. Moreover, this association persists in patients with borderline-resectable and locally advanced pancreatic cancer. Increasing the R0-resection rate is the most important potentially influenceable prognostic factor for improving surgery-related outcomes.

BACKGROUND:IPMN consensus guidelines make implicit judgments on what cancer risk level should prompt surgery. We used decision modeling to estimate this cancer risk threshold (CRT) for BD-IPMN patients. METHODS:We created a decision model to compare quality-adjusted life years (QALYs) following surgery or surveillance for BD-IPMNs. We simulated treatment decisions for hypothetical patients, varying age, comorbidities and lesion location (pancreatic head/tail). The base case was a 60-year-old patient with mild comorbidities and pancreatic head IPMN. Probabilities, life expectancies, and utilities were incorporated from literature/public datasets. CRT was defined as the level of cancer risk at which the expected value of QALYs for surgery first exceeded that of surveillance. RESULTS:In the base case, surgery was preferred over surveillance, yielding 21.90 vs. 21.88 QALYs. The optimal CRT for a BD-IPMN patient depended on age, comorbidities, and location. CRT in the base case was 20 % and 3 % for an IPMN in the head and tail of the pancreas, respectively. Other drivers of preferred treatment were age and likelihood of postoperative mortality. CONCLUSION/CONCLUSIONS:For BD-IPMNs, the optimal CRT varies depending on patient age and risk of surgical complications. Personalized risk threshold values could guide treatment decisions and inform future treatment consensus guidelines.

BACKGROUND:The existence of sociodemographic disparities in pancreatic cancer has been well-studied but how these disparities have changed over time is unclear. The purpose of this study was to longitudinally assess patient management in the context of sociodemographic factors to identify persisting disparities in pancreatic cancer care. METHODS:Using the National Cancer Database, patients diagnosed with pancreatic ductal adenocarcinoma from 2010 to 2017 were identified. The primary outcomes were surgical resection and/or receipt of chemotherapy. Outcome measures included changes in associations between sociodemographic factors (i.e., sex, age, race, comorbidity index, SES, and insurance type) and treatment-related factors (i.e., clinical stage at diagnosis, surgical resection, and receipt of chemotherapy). For each year, associations were assessed via univariate and multivariate analyses. RESULTS:Of 75,801 studied patients, the majority were female (51%), White (83%), and had government insurance (65%). Older age (range of OR 2010-2017 [range-OR]:0.19-0.29), Black race (range-OR: 0.61-0.78), lower SES (range-OR: 0.52-0.94), and uninsured status (range-OR: 0.46-0.71) were associated with lower odds of surgical resection (all p < 0.005), with minimal fluctuations over the study period. Older age (range-OR: 0.11-0.84), lower SES (range-OR: 0.41-0.63), and uninsured status (range-OR: 0.38-0.61) were associated with largely stable lower odds of receiving chemotherapy (all p < 0.005). CONCLUSIONS:Throughout the study period, age, SES, and insurance type were associated with stable lower odds for both surgery and chemotherapy. Black patients exhibited stable lower odds of resection underscoring the continued importance of mitigating racial disparities in surgery. Investigation of mechanisms driving sociodemographic disparities are needed to promote equitable care.

BACKGROUND:The American Joint Committee on Cancer (AJCC) eighth edition is based on pancreatic intraepithelial neoplasia-derived pancreatic ductal adenocarcinoma (PDAC), a biologically distinct entity from intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic cancer. The role of nodal disease and the AJCC's prognostic utility for IPMN-derived pancreatic cancer are unclear. This study aimed to evaluate the prognostic role of nodal disease and the AJCC eighth-edition N-staging for IPMN-derived pancreatic cancer. METHODS:Upfront-surgery patients with IPMN-derived PDAC from four centers were stratified according to the AJCC eighth-edition N stage. Disease characteristics were compared using descriptive statistics, and both overall survival (OS) and recurrence-free survival (RFS) were evaluated using log-rank tests. Multivariable Cox regression was performed to determine the prognostic value of N stage for OS, presented as hazard ratios with 95 % confidence intervals (95 % CIs). A lowest p value log-rank statistic was used to derive the optimal cutoff for node-positive disease. RESULTS:For 360 patients, advanced N stage was associated with worse T stage, grade, tubular histology, and perineural and lymphovascular invasion (all p < 0.05). The median OS was 98.3 months (95 % CI 82.8-122.0 months) for N0 disease, 27.8 months (95 % CI 24.4-41.7 months) for N1 disease, and 18.1 months (95 % CI 16.2-25.9 months) for N2 disease (p < 0.001). The AJCC N stage was validated and associated with worse OS (N1 [HR 1.64; range, 1.05-2.57], N2 [HR2.42; range, 1.48-3.96]) and RFS (N1 [HR 1.81; range, 1.23-2.68], N2 [HR 3.72; range, 2.40-5.77]). The optimal cutoff for positive nodes was five nodes. CONCLUSION/CONCLUSIONS:The AJCC eighth-edition N-staging is valid and prognostic for both OS and RFS in IPMN-derived PDAC.

BACKGROUND:Intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) is resected at smaller sizes compared to its biologically distinct counterpart, pancreatic intraepithelial neoplasia (PanIN)-derived PDAC. Thus, experts proposed T1 sub-staging for IPMN-derived PDAC. However, this has never been validated. METHODS:Consecutive upfront surgery patients with IPMN-derived PDAC from five international high-volume centers were classified by the proposed T1 sub-staging classification (T1a ≤ 0.5, T1b > 0.5 and ≤1.0, and T1c >1.0 and ≤2.0 cm) using the invasive component size. Kaplan-Meier and log-rank tests were utilized to compare overall survival (OS). A multivariable Cox-regression was used to determine hazard ratios (HR) with confidence intervals (95%CI). RESULTS:Among 747 patients, 69 (9.2%), 50 (6.7%), 99 (13.0%), and 531 patients (71.1%), comprised the T1a, T1b, T1c, and T2-4 subgroups, respectively. Increasing T-stage was associated with elevated CA19-9, poorer grade, nodal positivity, R1-margin, and tubular subtype. Median OS for T1a, T1b, T1c, and T2-4 were 159.0 (95%CI:126.0-NR), 128.8 (98.3-NR), 77.6 (48.3-108.2), and 31.4 (27.5-37.7) months, respectively (p < .001). OS decreased with increasing T-stage for all pairwise comparisons (all p < .05). After risk-adjustment, age > 65, elevated CA19-9, T1b [HR : 2.55 (1.22-5.32)], T1c [HR : 3.04 (1.60-5.76)], and T2-4 [HR : 3.41 (1.89-6.17)] compared to T1a, nodal positivity, R1-margin, and no adjuvant chemotherapy were associated with worse OS. Disease recurrence was more common in T2-4 tumors (56.4%) compared to T1a (18.2%), T1b (23.9%), and T1c (36.1%, p < .001). CONCLUSION/CONCLUSIONS:T1 sub-staging of IPMN-derived PDAC is valid and has significant prognostic value. Advancing T1 sub-stage is associated with worse histopathology, survival, and recurrence. T1 sub-staging is recommended for future guidelines.

BACKGROUND/OBJECTIVES/OBJECTIVE:Pancreatic cyst management can be distilled into three separate pathways - discharge, monitoring or surgery- based on the risk of malignant transformation. This study compares the performance of artificial intelligence (AI) models to clinical care for this task. METHODS:Two explainable boosting machine (EBM) models were developed and evaluated using clinical features only, or clinical features and cyst fluid molecular markers (CFMM) using a publicly available dataset, consisting of 850 cases (median age 64; 65 % female) with independent training (429 cases) and holdout test cohorts (421 cases). There were 137 cysts with no malignant potential, 114 malignant cysts, and 599 IPMNs and MCNs. RESULTS:The EBM and EBM with CFMM models had higher accuracy for identifying patients requiring monitoring (0.88 and 0.82) and surgery (0.66 and 0.82) respectively compared with current clinical care (0.62 and 0.58). For discharge, the EBM with CFMM model had a higher accuracy (0.91) than either the EBM model (0.84) or current clinical care (0.86). In the cohort of patients who underwent surgical resection, use of the EBM-CFMM model would have decreased the number of unnecessary surgeries by 59 % (n = 92), increased correct surgeries by 7.5 % (n = 11), identified patients who require monitoring by 122 % (n = 76), and increased the number of patients correctly classified for discharge by 138 % (n = 18) compared to clinical care. CONCLUSIONS:EBM models had greater sensitivity and specificity for identifying the correct management compared with either clinical management or previous AI models. The model predictions are demonstrated to be interpretable by clinicians.