Enhancer Reprogramming Promotes Pancreatic Cancer Metastasis.

Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal human malignancies, owing in part to its propensity for metastasis. Here, we used an organoid culture system to investigate how transcription and the enhancer landscape become altered during discrete stages of disease progression in a PDA mouse model. This approach revealed that the metastatic transition is accompanied by massive and recurrent alterations in enhancer activity. We implicate the pioneer factor FOXA1 as a driver of enhancer activation in this system, a mechanism that renders PDA cells more invasive and less anchorage-dependent for growth in vitro, as well as more metastatic in vivo. In this context, FOXA1-dependent enhancer reprogramming activates a transcriptional program of embryonic foregut endoderm. Collectively, our study implicates enhancer reprogramming, FOXA1 upregulation, and a retrograde developmental transition in PDA metastasis.

Patient-derived Organoid Pharmacotyping As A Predictive Tool for Therapeutic Selection in Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: We integrate a new approach to chemosensitivity data for clinically-relevant regimen matching, and demonstrate the relationship with clinical outcomes in a large PDO biobank. SUMMARY BACKGROUND DATA: Pancreatic ductal adenocarcinoma (PDAC) usually recurs following potentially curative resection. Prior studies related patient-derived organoid (PDO) chemosensitivity with clinical responses. METHODS: PDOs were established from pre-treatment biopsies in a multi-institution clinical trial (n=21) and clinical specimens at a high-volume pancreatectomy center (n=74, of which 48 were pre-treated). PDO in vitro chemosensitivities to standard-of-care chemotherapeutics (pharmacotypes) were matched to potential clinically-relevant regimens by a weighted nearest-neighbors analysis. Clinical outcomes were then compared for patients who had well-matched versus poorly-matched treatment according to this metric. RESULTS: Our function matched 91% of PDOs to a standard-of-care regimen (9% pan-resistant). PDOs poorly-matched to the neoadjuvant regimen received would have matched to an alternative in 34% of cases. Patients receiving neoadjuvant chemotherapy well-matched to their pharmacotype experienced improved CA 19-9 response (60% decreased to normal when well-matched, 29% when poorly-matched, P<0.05) and lymph node down-staging (33% N0 after poorly-matched, 69% after well-matched, P<0.05). Patients receiving both well-matched neoadjuvant and adjuvant chemotherapy experienced improved recurrence-free- and overall survival (median RFS 8.5 mo poorly-matched, 15.9 mo well-matched, P<0.05; median OS 19.5 vs. 30.3 mo, P<0.05). CONCLUSION: In vitro PDO pharmacotyping can inform PDAC therapy selection. We demonstrate improved outcomes including survival for patients treated with regimens well-matched to their PDO chemosensitivities. A subsequent prospective study using PDO pharmacotype matching could improve oncologic outcomes and improve quality of life by avoiding therapies not expected to be effective.

Poor Prognostic Factors in Long-Term Survivors of Resected Pancreatic Ductal Adenocarcinoma: An International, Multicenter Cohort Study.

OBJECTIVE: To measure the rate of LTS in resected PDAC and determine the association between predictors of OS and LTS. SUMMARY BACKGROUND DATA: Long-term survival (>5 y, LTS) remains rare in pancreatic ductal adenocarcinoma (PDAC). Multiple predictors of overall survival (OS) are known but their association with LTS remains unclear. METHODS: An international, multicenter retrospective study was conducted. Included were patients from 2012-2019 with resected PDAC. Excluded were those with metastases at diagnosis or resection, R2 resections, and 90-day mortality. Predictors of OS were identified using multivariable Cox regression and their prevalence in patients with LTS assessed. LTS was calculated by excluding patients with shorter follow-up and predictors of LTS were identified using multivariable logistic regression. RESULTS: 3,003 patients were included (27.4% received neoadjuvant chemotherapy). Elevated baseline CA19-9, high tumor grade, nodal disease, and perineural and lymphovascular invasion were negative independent predictors of OS, while receipt of adjuvant chemotherapy predicted improved OS (all P<0.05). LTS was observed in 220/2,436 patients (9.0%), of whom 198 (90%) harbored poor prognostic factors: elevated baseline CA19-9 (58.1%), poor tumor differentiation (51.0%), nodal disease (46.8%), and perineural invasion (76.0%). Of those without any of these four features, 50.0% achieved LTS as compared to 21.3%, 13.3%, 5.2%, and 3.5% in those with 1, 2, 3, or 4 features. CONCLUSIONS: This bi-national cohort demonstrates a true LTS rate of 9.0% in resected PDAC. Clinicians should remain aware that presence of poor prognostic factors does not preclude LTS.

Sociodemographic variation in the utilization of minimally invasive surgical approaches for pancreatic cancer.

BACKGROUND: Minimally invasive pancreatic surgery (MIPS), when selectively utilized, has been shown to hasten recovery with outcomes comparable to open approaches, but access may not be equitable. This study explored variation in utilization of MIPS for pancreatic cancer. METHODS: The National Cancer Database was queried to identify patients diagnosed with a primary pancreatic neoplasm from 2010 to 2020. Study participants had diagnoses of clinical or pathologic stage 1-3 disease and received curative-intent surgery. Multivariable analyses assessed the association between surgical approach and patient and disease factors. RESULTS: Inclusion criteria identified 73,137 patients: 51,408 underwent open surgery and 21,729 received MIPS. In our multivariable analysis, Black race was associated with reduced odds of MIPS (AOR 0.88; p = 0.02), while older age (AOR 1.17; p = 0.01), later year of diagnosis (AOR 1.57; p < 0.001), and private insurance coverage (AOR 1.30; p = 0.05) were associated with increased odds. When patients with adenocarcinoma were analyzed in isolation, disparities in MIPS utilization persisted even when controlling for disease stage. CONCLUSION: Sociodemographic factors like age, race, and insurance coverage appear to vary in the utilization of MIPS technologies for the treatment of pancreatic malignancy. Addressing variation with robust mixed methods approaches in the future is proposed to incorporate prospective interventions with highly annotated outcomes for additional study.

Persistent Circulating Tumor Cells at 1 Year After Oncologic Resection Predict Late Recurrence in Pancreatic Cancer.

OBJECTIVE: The aim of the study was to assess the association between persistent circulating tumor cells (CTCs) and subsequent recurrence in patients who were clinically recurrence free ~12 months postoperatively. BACKGROUND: Circulating tumor cells have been proposed as biomarkers to predict survival in pancreatic cancer. Some patients demonstrate persistent CTCs postoperatively, which could represent minimal residual disease. METHODS: Patients from previously published prospective circulating tumor cell in pancreatic cancer trial without clinical evidence of recurrence 12 months postoperatively and CTC testing performed 9 to 15 months postoperatively were included. The presence of epithelial and transitional CTCs (trCTCs) was evaluated as predictor of recurrence. Kaplan-Meier curve, log-rank test, and Cox model were used for survival analysis. RESULTS: Thirty-three of 129 eligible patients (circulating tumor cell in pancreatic cancer trial) were included. The trCTC-positive and negative patients were well balanced in clinicopathologic features. Patients with trCTCs had a recurrence rate per-person-month of 10.3% compared with 3.1% in trCTCs-negative patients with a median time to recurrence of 3.9 versus 27.1 months, respectively. On multivariable analysis, trCTCs positivity was associated with higher risk of late recurrence (hazard ratio: 4.7, 95% CI, 1.2-18.3, P =0.024). Fourteen (42.4%) patients recurred during the second postoperative year. One-year postoperative trCTCs positivity was associated with a higher rate of recurrence during the second year (odds ratio:13.1, 95% CI, 1.6-1953.4, P =0.028, area under curve=0.72). Integrating clinicopathologic features with trCTCs increased the area under curve to 0.80. A majority of trCTCs-positive patients (N=5, 62.5%) had multisite recurrence, followed by local-only (N=2, 25.0%) and liver-only (N=1, 12.5%) recurrence. This was in striking contrast to trCTCs-negative patients, where a majority (N=6, 66.7%) had a local-only recurrence, followed by liver-only (N=2, 22.2%) and multisite (N=1, 11.1%) recurrence. CONCLUSIONS: In patients deemed to be clinically disease-free 12 months postoperatively, trCTCs positivity is associated with higher rates of subsequent recurrence with distinct patterns of recurrence. CTCs could be used a putative biomarker to guide patient prognostication and management in pancreatic cancer.

Conduits in Vascular Pancreatic Surgery: Analysis of Clinical Outcomes, Operative Techniques, and Graft Performance.

OBJECTIVES: We analyze successes and failures of pushing the boundaries in vascular pancreatic surgery to establish safety of conduit reconstructions. 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.

Surgical Decision-Making in Pancreatic Ductal Adenocarcinoma: Modeling Prognosis Following Pancreatectomy in the Era of Induction and Neoadjuvant Chemotherapy.

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 and 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 overall survival (OS) and recurrence-free survival (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 andthe 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: 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.

A Delay in Adjuvant Therapy Is Associated With Worse Prognosis Only in Patients With Transitional Circulating Tumor Cells After Resection of Pancreatic Ductal Adenocarcinoma.

OBJECTIVES: The aim of the study was to assess the association of circulating tumor cells (CTCs) with survival as a biomarker in pancreatic ductal adenocarcinoma (PDAC) within the context of a delay in the initiation of adjuvant therapy. BACKGROUND: Outcomes in patients with PDAC remain poor and are driven by aggressive systemic disease. Although systemic therapies improve survival in resected patients, factors such as a delay in the initiation of adjuvant therapy are associated with worse outcomes. CTCs have previously been shown to be predictive of survival. METHODS: A retrospective study was performed on PDAC patients enrolled in the prospective CircuLating tUmor cellS in pancreaTic cancER trial (NCT02974764) on CTC-dynamics at the Johns Hopkins Hospital. CTCs were isolated based on size (isolation by size of epithelial tumor cells; Rarecells) and counted and characterized by subtype using immunofluorescence. The preoperative and postoperative blood samples were used to identify 2 CTC types: epithelial CTCs (eCTCs), expressing pancytokeratin, and transitional CTCs (trCTCs), expressing both pancytokeratin and vimentin. Patients who received adjuvant therapy were compared with those who did not. A delay in the receipt of adjuvant therapy was defined as the initiation of therapy ≥8 weeks after surgical resection. Clinicopathologic features, CTCs characteristics, and outcomes were analyzed. RESULTS: Of 101 patients included in the study, 43 (42.5%) experienced a delay in initiation and 20 (19.8%) did not receive adjuvant therapy. On multivariable analysis, the presence of trCTCs ( P =0.002) and the absence of adjuvant therapy ( P =0.032) were associated with worse recurrence-free survival (RFS). Postoperative trCTC were associated with poorer RFS, both in patients with a delay in initiation (12.4 vs 17.9 mo, P =0.004) or no administration of adjuvant chemotherapy (3.4 vs NR, P =0.016). However, it was not associated with RFS in patients with timely initiation of adjuvant chemotherapy ( P =0.293). CONCLUSIONS: Postoperative trCTCs positivity is associated with poorer RFS only in patients who either experience a delay in initiation or no receipt of adjuvant therapy. This study suggests that a delay in the initiation of adjuvant therapy could potentially provide residual systemic disease (trCTCs) a window of opportunity to recover from the surgical insult. Future studies are required to validate these findings and explore the underlying mechanisms involved.

Early Recurrence After Resection of Locally Advanced Pancreatic Cancer Following Induction Therapy: An International Multicenter Study.

OBJECTIVE: To establish an evidence-based cutoff and predictors for early recurrence in patients with resected locally advanced pancreatic cancer (LAPC). BACKGROUND: It is unclear how many and which patients develop early recurrence after LAPC resection. Surgery in these patients is probably of little benefit. METHODS: We analyzed all consecutive patients undergoing resection of LAPC after induction chemotherapy who were included in prospective databases in The Netherlands (2015-2019) and the Johns Hopkins Hospital (2016-2018). The optimal definition for "early recurrence" was determined by the post-recurrence survival (PRS). Patients were compared for overall survival (OS). Predictors for early recurrence were evaluated using logistic regression analysis. RESULTS: Overall, 168 patients were included. After a median follow-up of 28 months, recurrence was observed in 118 patients (70.2%). The optimal cutoff for recurrence-free survival to differentiate between early (n=52) and late recurrence (n=66) was 6 months ( P <0.001). OS was 8.4 months [95% confidence interval (CI): 7.3-9.6] in the early recurrence group (n=52) versus 31.1 months (95% CI: 25.7-36.4) in the late/no recurrence group (n=116) ( P <0.001). A preoperative predictor for early recurrence was postinduction therapy carbohydrate antigen (CA) 19-9≥100 U/mL [odds ratio (OR)=4.15, 95% CI: 1.75-9.84, P =0.001]. Postoperative predictors were poor tumor differentiation (OR=4.67, 95% CI: 1.83-11.90, P =0.001) and no adjuvant chemotherapy (OR=6.04, 95% CI: 2.43-16.55, P <0.001). CONCLUSIONS: Early recurrence was observed in one third of patients after LAPC resection and was associated with poor survival. Patients with post-induction therapy CA 19-9 ≥100 U/mL, poor tumor differentiation and no adjuvant therapy were especially at risk. This information is valuable for patient counseling before and after resection of LAPC.

The Impact of Clinical and Pathological Features on Intraductal Papillary Mucinous Neoplasm Recurrence After Surgical Resection: Long-Term Follow-Up Analysis.

OBJECTIVE: This study aimed to identify risk factors for recurrence after pancreatic resection for intraductal papillary mucinous neoplasm (IPMN). SUMMARY BACKGROUND DATA: Long-term follow-up data on recurrence after surgical resection for IPMN are currently lacking. Previous studies have presented mixed results on the role of margin status in risk of recurrence after surgical resection. METHODS: A total of 126 patients that underwent resection for noninvasive IPMN were followed for a median of 9.5 years. Dedicated pathological and radiological reviews were performed to correlate clinical and pathological features (including detailed pathological features of the parenchymal margin) with recurrence after surgical resection. In addition, in a subset of 32 patients with positive margins, we determined the relationship between the margin and original IPMN using driver gene mutations identified by next-generation sequencing. RESULTS: Family history of pancreatic cancer and high-grade IPMN was identified as risk factors for recurrence in both uni- and multivariate analysis (adjusted hazard ratio 3.05 and 1.88, respectively). Although positive margin was not significantly associated with recurrence in our cohort, the size and grade of the dysplastic focus at the margin were significantly correlated with recurrence in margin-positive patients. Genetic analyses showed that the neoplastic epithelium at the margin was independent from the original IPMN in at least 9 of 32 cases (28%). The majority of recurrences (74%) occurred after 3 years, and a significant minority (32%) occurred after 5 years. CONCLUSION: Sustained postoperative surveillance for all patients is indicated, particularly those with risk factors such has family history and high-grade dysplasia.