Faculty Bibliography

OBJECTIVES/OBJECTIVE:We analyze successes and failures of pushing the boundary in vascular pancreatic surgery to establish safety of conduit reconstructions. SUMMARY BACKGROUND DATA/BACKGROUND:Improved systemic control from chemotherapy in pancreatic cancer is increasing the demand for surgical solutions of extensive local vessel involvement, but conduit-specific data are scarce. METHODS:We identified 63 implanted conduits (41% autologous vessels, 37% allografts, 18% PTFE) in 56 pancreatic resections of highly selected cancer patients between October 2013 and July 2020 from our prospectively maintained database. Assessed parameters were survival, perioperative complications, operative techniques (anatomic and extra-anatomic routes) and conduit patency. RESULTS:For vascular reconstruction, 25 arterial and 38 venous conduits were utilized during 39 pancreatoduodenectomies, 14 distal pancreatectomies and 3 total pancreatectomies. The median postoperative survival was 2 years. A Clavien-Dindo grade ≥IIIa complication was apparent in 50% of the patients with a median Comprehensive Complication Index of 29.6. The 90-day mortality in this highly selected cohort was 9%. Causes of mortality were conduit-related in 3 patients, late postpancreatectomy hemorrhage in 1 patient and early liver metastasis in 1 patient. Image-based patency rates of conduits were 66% and 45% at postoperative days 30 and 90, respectively. CONCLUSIONS:Our perioperative mortality of vascular pancreatic surgery with conduits in the arterial or venous system is 9%. Reconstructions are technically feasible with different anatomic and extra-anatomic strategies, while identifying predictors of early conduit occlusion remains challenging. Optimizing reconstructed arterial and venous hemodynamics in the context of pancreatic malignancy will enable long-term survival in more patients responsive to chemotherapies.

OBJECTIVES/OBJECTIVE:To identify factors associated with concordance between World Health Organization (WHO) grade on cytological analysis (c-grade) and histopathological analysis (h-grade) of surgical specimen in patients with PanNETs and examine trends in utilization and accuracy of EUS-FNA in preoperatively predicting grade. BACKGROUND:WHO grading system is prognostic in pancreatic neuroendocrine tumors (PanNETs). The concordance between c-grade and h-grade is reported to be between 60% and 80%. METHODS:A multicenter retrospective study was performed on patients undergoing resection for PanNETs at four high-volume centers. Patients with functional or syndrome-associated tumors, and those receiving neoadjuvant therapy were excluded. Factors associated with concordance between c-grade and h-grade and trends of utilization of EUS-FNA were assessed. RESULTS:Of 1,336 patients included, 682 (51.1%) underwent EUS-FNA; 567 (83.1%) were diagnostic of PanNETs and WHO-grade was reported for 293 (51.7%) patients. The concordance between c-grade and h-grade was 78.2% with moderate inter-rater agreement (Kc=0.48,p<0.001). Significantly higher rates of concordance were observed in patients with smaller tumors (<2 vs. ≥2 cm, 88.9% vs. 72.7%,p=0.001). Highest concordance (97.9%) was observed in patients with small tumors undergoing assessment between 2015-2019 with near-perfect inter-rater agreement (Kc=0.88,p<0.001)An increase in the utilization of EUS-FNA (46.7% to 62.1%) was observed over the last 2 decades (p<0.001). EUS-FNA was more frequently diagnostic of PanNETs (p<0.001), and WHO-grade was more frequently reported (<0.001). However, concordance between c-grade and h-grade did not change significantly (p=0.056). CONCLUSION/CONCLUSIONS:Recently, a trend towards increasing utilization and improved diagnostic accuracy of EUS-FNA has been observed in PanNETs. Concordance between c-grade and h-grade is associated with tumor size with near-perfect agreement when assessing PanNETs >2 cm in size.

OBJECTIVE:To validate the 7th and 8th editions of the American Joint Committee on Cancer (AJCC) staging system for patients with invasive carcinomas arising in association with IPMN (IPMN-associated PDAC). BACKGROUND DATA/BACKGROUND:Although several studies have validated AJCC systems in patients with conventional PDAC, their applicability to IPMN-associated PDAC has not been assessed. METHODS:275 patients who underwent resection for IPMN-associated PDAC between 1996 and 2015 at three tertiary centers and had data on the size of the invasive component and lymph node status were identified. Concordance probability estimates (CPE) were calculated and recursive partitioning analysis was employed to identify optimal prognostic cutoffs for T and N. RESULTS:The CPE for both the 7th and 8th editions of the AJCC schema was relatively good (0.64 in both) and similar for colloid and tubular subtypes (0.64 in both). The 8th edition introduced T1a sub-staging and a new distinction between N1 and N2. The utility of the former was confirmed, although the latter did not improve prognostic discrimination. The successful validation of the 8th edition of the AJCC criteria in patients with tubular and colloid subtypes allowed us to compare these patients in early vs late T and N stages which showed that when there is advanced disease, the prognostic superiority of colloid tumors over their tubular counterparts diminishes. CONCLUSIONS:Our findings support the use of the AJCC 8th edition in the IPMN-associated PDAC population, but suggest that certain cutoffs may need to be revisited. In advanced AJCC stages, patients with colloid vs tubular subtype have comparable prognosis.

BACKGROUND:Although we previously proposed a nomogram to predict malignancy in intraductal papillary mucinous neoplasms (IPMN) and validated it in an external cohort, its application is challenging without data on tumor markers. Moreover, existing nomograms have not been compared. This study aimed to develop a nomogram based on radiologic findings and to compare its performance with previously proposed American and Korean/Japanese nomograms. METHODS:We recruited 3708 patients who underwent surgical resection at 31 tertiary institutions in eight countries, and patients with main pancreatic duct >10 mm were excluded. To construct the nomogram, 2606 patients were randomly allocated 1:1 into training and internal validation sets, and area under the receiver operating characteristics curve (AUC) was calculated using 10-fold cross validation by exhaustive search. This nomogram was then validated and compared to the American and Korean/Japanese nomograms using 1102 patients. RESULTS:Among the 2606 patients, 90 had main-duct type, 900 had branch-duct type, and 1616 had mixed-type IPMN. Pathologic results revealed 1628 low-grade dysplasia, 476 high-grade dysplasia, and 502 invasive carcinoma. Location, cyst size, duct dilatation, and mural nodule were selected to construct the nomogram. AUC of this nomogram was higher than the American nomogram (0.691 vs 0.664, P = .014) and comparable with the Korean/Japanese nomogram (0.659 vs 0.653, P = .255). CONCLUSIONS:A novel nomogram based on radiologic findings of IPMN is competitive for predicting risk of malignancy. This nomogram would be clinically helpful in circumstances where tumor markers are not available. The nomogram is freely available at http://statgen.snu.ac.kr/software/nomogramIPMN.

OBJECTIVE:To develop a predictive model of oncologic outcomes for patients with pancreatic ductal adenocarcinoma (PDAC) undergoing resection after neoadjuvant or induction chemotherapy use. BACKGROUND:Early recurrence following surgical resection for PDAC is common. The use of neoadjuvant chemotherapy prior to resection may increase the likelihood of long-term systemic disease control. Accurately characterizing an individual's likely oncologic outcome in the perioperative setting remains challenging. METHODS:Data from patients with PDAC who received chemotherapy prior to pancreatectomy at a single high-volume institution between 2007-2018 were captured in a prospectively collected database. Core clinicopathologic data were reviewed for accuracy and survival data were abstracted from the electronic medical record and national databases. Cox-proportional regressions were used to model outcomes and develop an interactive prognostic tool for clinical decision-making. RESULTS:A total of 581 patients were included with a median OS and RFS of 29.5 (26.5-32.5) and 16.6 (15.8-17.5) months, respectively. Multivariable analysis demonstrates OS and RFS were associated with type of chemotherapeutic used and the number of chemotherapy cycles received preoperatively. Additional factors contributing to survival models included: tumor grade, histopathologic response to therapy, nodal status, and administration of adjuvant chemotherapy. The models were validated using an iterative bootstrap method and with randomized cohort splitting. The models were well calibrated with concordance indices of 0.68 and 0.65 for the final OS and RFS models, respectively. CONCLUSION/CONCLUSIONS:We developed an intuitive and dynamic decision-making tool that can be useful in estimating OS, RFS and location-specific disease recurrence rates. This prognostic tool may add value to patient care in discussing the benefits associated with surgical resection for PDAC.

BACKGROUND:The introduction of multi-agent chemotherapy and radiation therapy has facilitated potential resection with curative intent in selected locally advanced pancreatic cancer (LAPC) patients with excellent outcomes. Nevertheless, there remains a remarkable lack of consensus on the management of LAPC. We sought to describe the outcomes of patients with LAPC and objectively define the multidisciplinary selection process for operative exploration based on anatomical factors. METHODS:Consecutive patients with LAPC were evaluated for pancreatic surgery in the multidisciplinary clinic of a high-volume institution, between 2013 and 2018. Prospective stratification (LAPC-1, LAPC-2, and LAPC-3), based on the involvement of regional anatomical structures, was performed at the time of presentation prior to the initiation of treatment. Resection rates and patient outcomes were evaluated and correlated with the initial anatomic stratification system. RESULTS:Overall, 415 patients with LAPC were included in the study, of whom 84 (20%) were successfully resected, with a median overall survival of 35.3 months. The likelihood of operative exploration was associated with the pretreatment anatomic LAPC score, with a resection rate of 49% in patients classified as LAPC-1, 32% in LAPC-2, and 11% in LAPC-3 (p < 0.001). Resected patients with improvement of the LAPC score at the time of exploration had significantly longer median overall survival compared with those with no change or progression of LAPC score (60.7 vs. 29.8 months, p = 0.006). CONCLUSIONS:Selected patients with LAPC can undergo curative-intent surgery with excellent outcomes. The proposed Johns Hopkins anatomic LAPC score provides an objective system to anticipate the probability of eventual surgical resection after induction therapy.

PURPOSE:may also mutate and confer the HR-DDR deficiency in pancreatic ductal adenocarcinoma (PDAC). METHODS:We conducted a study to examine the genetic alterations using a companion diagnostic 15-gene HR-DDR panel in PDACs. HR-DDR gene mutations were identified and characterized by whole-exome sequencing and whole-genome sequencing. Different HR-DDR gene mutations are associated with variable homologous recombination deficiency (HRD) scores. RESULTS:is not the gene panel for germline tests. CONCLUSION:in the germline test of HR-DDR pathway genes.

BACKGROUND:The American Joint Committee on Cancer (AJCC) made improvements for staging pancreatic neuroendocrine tumors (pNETs) in its 8th Edition; however, multicenter studies were not included. METHODS:We collected multicenter datasets (n = 1,086, between 2004 and 2018) to validate the value of AJCC 8 and other coexisting staging systems through univariate and multivariate analysis for well-differentiated (G1/G2) pNETs. RESULTS:Compared to other coexisting staging systems, AJCC 7 only included 12 (1.1%) patients with stage III tumors. Patients with European Neuroendocrine Tumor Society (ENETS) stage IIB disease had a higher risk of death than patients with stage IIIA (hazard ratio [HR]: 4.376 vs. 4.322). For the modified ENETS staging system, patients with stage IIB disease had a higher risk of death than patients with stage III (HR: 6.078 vs. 5.341). According to AJCC 8, the proportions of patients with stage I, II, III, and IV were 25.7%, 40.3%, 23.6%, and 10.4%, respectively. As the stage advanced, the median survival time decreased (NA, 144.7, 100.8, 72.0 months, respectively), and the risk of death increased (HR: II = 3.145, III = 5.925, and IV = 8.762). CONCLUSION:These findings suggest that AJCC 8 had a more reasonable proportional distribution and the risk of death was better correlated with disease stage.