The Landmark Series: Locally Advanced Pancreatic Cancer and Ablative Therapy Options

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.

Multi-institutional review of adverse events associated with irreversible electroporation in the treatment of locally advanced pancreatic cancer

BACKGROUND

Irreversible electroporation is a novel approach for treating locally advanced pancreatic adenocarcinoma. However, this ablative technique is not without risk and has the potential to precipitate adverse events. The aim of this study was to delineate risk factors that increase this risk, as well as to elucidate the risk profile associated with irreversible electroporation in the setting of locally advanced pancreatic adenocarcinoma.

METHODS

A review of our prospective multi-institutional database from December 2015 to March 2022 of patients with locally advanced pancreatic adenocarcinoma who underwent irreversible electroporation was analyzed for adverse events. These were then compared with a control population of patients undergoing pancreatectomy for adenocarcinoma.

RESULTS

Adverse events occurred in 51 patients of the 201 patients treated with irreversible electroporation compared with 78 of the 200 patients treated with pancreatectomy. The irreversible electroporation group had a significantly greater incidence of postoperative ascites in stage 3C patients. The most common complications in the irreversible electroporation group were infectious (n = 13), gastrointestinal bleed (n = 11), and ascites (n = 7). Multivariate analysis demonstrated increased risk of severe (grade ≥3) adverse events in the irreversible electroporation cohort who received high dose, neoadjuvant radiation (hazard ratio, 2.4; 95% confidence interval, 1.4-5.4), irreversible electroporation electrodes bracketing the superior mesenteric artery, superior mesenteric vein, and portal venous vein (hazard ratio, 1.9; 95% confidence interval, 1.3-3.4), and who had a bile duct stent in place for >6 months (hazard ratio, 1.7; 95% confidence interval, 1.2-5.6). There were similar rates of 90-day mortality in both groups, irreversible electroporation 2.4% vs pancreatectomy 2.8%.

CONCLUSION

This study revealed a 25% rate of adverse events associated with irreversible electroporation in locally advanced pancreatic adenocarcinoma, which was significantly less (P = .004) than the 39% rate of adverse events associated with pancreatectomy in early-stage disease. Certain unique adverse events in the irreversible electroporation group have been established and should be understood in the care of these patients.

Preoperative chemotherapy, radiotherapy and surgical decision-making in patients with borderline resectable and locally advanced pancreatic cancer

Surgical resection combined with systemic chemotherapy is the cornerstone of treatment for patients with localized pancreatic cancer. Upfront surgery is considered suboptimal in cases with extensive vascular involvement, which can be classified as either borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In these patients, FOLFIRINOX or gemcitabine plus nab-paclitaxel chemotherapy is currently used as preoperative chemotherapy and is eventually combined with radiotherapy. Thus, more patients might reach 5-year overall survival. Patient selection for chemotherapy, radiotherapy and subsequent surgery is based on anatomical, biological and conditional parameters. Current guidelines and clinical practices vary considerably regarding preoperative chemotherapy and radiotherapy, response evaluation, and indications for surgery. In this Review, we provide an overview of the clinical evidence regarding disease staging, preoperative therapy, response evaluation and surgery in patients with borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In addition, a clinical work-up is proposed based on the available evidence and guidelines. We identify knowledge gaps and outline a proposed research agenda.

"Conversion surgery" for locally advanced pancreatic cancer: A position paper by the study group at the joint meeting of the International Association of Pancreatology (IAP) & Japan Pancreas Society (JPS) 2022

Locally advanced pancreatic cancer (LAPC), which progresses locally and surrounds major vessels, has historically been deemed unresectable. Surgery alone failed to provide curative resection and improve overall survival. With the advancements in treatment, reports have shown favorable results in LAPC after undergoing successful chemotherapy therapy or chemoradiation therapy followed by surgical resection, so-called "conversion surgery", at experienced high-volume centers. However, recognizing significant regional and institutional disparities in the management of LAPC, an international consensus meeting on conversion surgery for LAPC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of Japan Pancreas Society (JPS) in Kyoto in July 2022. During the meeting, presenters reported the current best multidisciplinary practices for LAPC, including preoperative modalities, best systemic treatment regimens and durations, procedures of conversion surgery with or without vascular resections, biomarkers, and genetic studies. It was unanimously agreed among the experts in this meeting that "cancer biology is surpassing locoregional anatomical resectability" in the era of effective multiagent treatment. The biology of pancreatic cancer has yet to be further elucidated, and we believe it is essential to improve the treatment outcomes of LAPC patients through continued efforts from each institution and more international collaboration. This article summarizes the agreement during the discussion amongst the experts in the meeting. We hope that this will serve as a foundation for future international collaboration and recommendations for future guidelines.

Infection reporting in patients undergoing irreversible electroporation of locally advanced pancreatic cancer

BACKGROUND

Intraoperative bile cultures (IOBCs) taken during pancreatic surgery are commonly performed and there has been limited evidence that a positive IOBC could aid in perioperative adverse event (AE) management. Therefore, this study aims to describe infection management in patients undergoing irreversible electroporation (IRE).

METHODS

An Institutional Review Board (IRB)-approved prospective database was utilized from 8/2016 to 6/2022, with 127 pancreatic adenocarcinoma patients included.

RESULTS

A total of 28 patients that underwent IRE also had a simultaneous positive IOBC and the remaining 99 patients that underwent IRE had negative IOBC. A total of 11(39%) of the patients with a positive IOBC had AE's, and 38 (38%) of the patients with negative IOBC had AE's. Both groups had similar rates of AEs leading to new hospitalization and prolonged hospitalizations. Overall, there was no correlation between a positive IOBC and a patient developing an AE.

CONCLUSIONS

The findings of this study provide insights that improve the infectious management of patients undergoing IRE.

Impact of margin accentuation with intraoperative irreversible electroporation on local recurrence in resected pancreatic cancer

BACKGROUND

The purpose of this study was to evaluate the rates of local recurrence and margin positivity in patients with borderline resectable pancreatic cancer after pancreatectomy with or without irreversible electroporation with margin accentuation.

METHODS

Prospective data for preoperative stages IIB (borderline resectable) and III were evaluated, with 75 patients undergoing pancreatectomy with irreversible electroporation with margin accentuation compared to 71 patients who underwent pancreatectomy alone from March 2010 to November 2020.

RESULTS

Both irreversible electroporation with margin accentuation and pancreatectomy-alone groups were similar for body mass index, Charleston comorbidity index, and sex. The irreversible electroporation with margin accentuation group had significantly greater preoperative stage III (irreversible electroporation 83% vs pancreatectomy alone 51%; P = .0001), with similar tumor location (head 64% vs 72%) and tumor size (median 2.9 vs 2.8). Neoadjuvant/induction chemotherapy and prior radiation therapy was similar in both groups (irreversible electroporation with margin accentuation 89% vs 72%). Surgical therapy included a greater percentage of pancreaticoduodenectomy in the pancreatectomy-alone group. Despite greater stage and greater percentage of margin positivity (irreversible electroporation with margin accentuation 27% vs 20%; P = not significant), rates of local recurrence were similar. The mean disease-free interval for local recurrence from time of diagnosis was similar (irreversible electroporation with margin accentuation 15.8 vs 16.5 pancreatectomy alone; P = not significant) and time of treatment (irreversible electroporation with margin accentuation 9.4 vs 10.5 months; P = not significant). Overall survival was improved with the irreversible electroporation with margin accentuation group, with a mean of 34.2 months versus 27.9 months in the pancreatectomy-alone group.

CONCLUSION

Irreversible electroporation with margin accentuation is safe and effective in stages IIB and III pancreatic adenocarcinomas that are technically resectable. Despite higher margin positivity rates, the time to local recurrence and the effects of recurrence were the same in the pancreatectomy-alone group.

Pancreatic cancer

The need for a common education and training track in surgical oncology across Europe has been emphasized. ESSO provides several hands-on courses for skills training and face-to-face discussions. The core curriculum provides a framework for the overall theoretical requirements in surgical oncology. The UEMS/EBSQ fellowship exam is designed to test core competencies in the candidate's core knowledge in their prespecified area of expertise. A core set of points for each cancer type is lacking. Hence, a condensed outline of themed expected to be covered in the curriculum and relevant to an optimal practice in surgical oncology is provided. This article outlines pancreatic cancer.

Endoscopic Ultrasound-Guided Pancreatic Interstitial Laser Ablation Using a Cylindrical Laser Diffuser: A Long-Term Follow-Up Study

BACKGROUND AND AIMS

Local ablative treatment is another option for improving outcomes and has been evaluated for locally advanced pancreatic cancer. We previously suggested endoscopic ultrasound (EUS)-guided interstitial laser ablation using a cylindrical laser diffuser (CILA) might be a feasible therapeutic option based on experiments performed on pancreatic cancer cell lines and porcine model with a short follow-up (3 days). The aim of this study was to investigate the safety of EUS-CILA performed using optimal settings in porcine pancreas with a long-term follow-up (2 weeks).

METHODS

EUS-CILA (laser energy of 450 J; 5 W for 90 s) was applied to normal pancreatic tissue in porcine (n = 5) under EUS guidance. Animals were observed clinically for 2 weeks after EUS-CILA to evaluate complications. Computed tomography and laboratory tests were carried out to evaluate safety. Two weeks after EUS-CILA, all pigs were sacrificed, and histopathological safety and efficacy evaluations were conducted.

RESULTS

EUS-CILA was technically successful in all five cases. No major complications occurred during the follow-up period. Body weight of porcine did not change during the study period without any significant change in feed intake. Animals remained in excellent condition throughout the experimental period, and laboratory tests and computed tomography (CT) scans provided no evidence of a major complication. Histopathological evaluation showed complete ablation in the ablated area with clear delineation of surrounding normal pancreatic tissue. Mean ablated volume was 55.5 mm² × 29.0 mm and mean ablated areas in the pancreatic sections of the five pigs were not significantly different (p = 0.368).

CONCLUSIONS

In conclusion, our experimental study suggests that EUS-CILA is safe and has the potential to be an effective local treatment modality. No major morbidity or mortality occurred during the study period. Further evaluations are warranted before clinical application.

Optimizing Patient Selection for Irreversible Electroporation of Locally Advanced Pancreatic Cancer: Analyses of Survival

Background

Irreversible electroporation (IRE) has emerged as a viable consolidative therapy after induction chemotherapy, in which this combination has improved overall survival of locally advanced pancreatic cancer (LAPC). Optimal timing and patient selection for irreversible electroporation remains a clinically unmet need. The aim of this study was to investigate preoperative factors that may assist in predicting progression-free and overall survival following IRE.

Methods

A multi-institutional, prospectively maintained database was reviewed for patients with LAPC treated with induction chemotherapy followed by open-technique irreversible electroporation from 7/2015-5/2019. RECIST 1.1 criteria were used to assess tumor response and radiological progression. Overall survival (OS) and progression-free survival (PFS) were recorded. Survival analyses were performed using Kaplan Meier and Cox multivariable regression analyses.

Results

187 LAPC patients (median age 62 years range, 21 – 91, 65% men, 35% women) were treated with IRE. Median PFS was 21.7 months and median OS from diagnosis was 25.5 months. On multivariable analysis, age ≤ 61 (HR 0.41, 95%CI 0.21-0.78, p<0.008) and no prior radiation (HR 0.49, 95%CI 0.26-0.94, p=0.03) were positive predictors of OS after IRE. Age ≤ 61(HR 0.53, 95%CI, 0.28-.99, p=0.046) and FOLFIRINOX followed by gemcitabine/abraxane induction chemotherapy (HR 0.37,95%CI 0.15-0.89, p=0.027) predicted prolonged PFS after IRE. Abnormal CA19-9 values at the time of surgery negatively impacted both OS (HR 2.46, 95%CI 1.28-4.72, p<0.007) and PFS (HR 2.192, 95%CI 1.143-4.201, p=0.018) following IRE.

Conclusions

Age, CA 19-9 response, avoidance of pre-IRE radiation, and FOLFIRINOX plus gemcitabine/abraxane induction chemotherapy are prominent factors to consider when referring or selecting LAPC patients to undergo IRE.