Survival Comparison of Neoadjuvant Chemotherapy Followed by Irreversible Electroporation Versus Conversional Resection for Locally Advanced Pancreatic Cancer

Long-term follow-up experience with adjuvant therapy after irreversible electroporation of locally advanced pancreatic cancer

BACKGROUND

Irreversible electroporation (IRE) expands the surgical options for patients with unresectable pancreatic cancer. This study evaluated for differences in survival stratified by type of IRE and receipt of adjuvant chemotherapy.

METHODS

Patients with locally advanced pancreatic cancer treated by IRE (2012-2020) were retrospectively included. Overall survival (OS) and recurrence-free survival (RFS) were compared by type of IRE (in situ for local tumor control or IRE of potentially positive margins with resection) and by receipt of adjuvant chemotherapy.

RESULTS

Thirty-nine patients had IRE in situ, 61 had IRE for margin extension, and 19 received adjuvant chemotherapy. Most (97.00%) underwent induction chemotherapy. OS was 28.71 months (interquartile range [IQR] 19.17, 51.19) from diagnosis, with no difference by IRE type (hazard ratio [HR] 1.05 for margin extension [p = 0.85]) or adjuvant chemotherapy (HR 1.14 [p = 0.639]). RFS was 8.51 months (IQR 4.95, 20.17) with no difference by IRE type (HR 0.90 for margin extension [p = 0.694]) or adjuvant chemotherapy (HR 0.90 [p = 0.711]).

CONCLUSION

These findings suggest that adjuvant therapy may have limited benefit for patients treated with induction chemotherapy followed by local control with IRE for unresectable pancreatic cancer. Further study of the duration and timing of systemic therapy is warranted to maximize benefit and limit toxicity.

Pancreatic Cancer: Challenges and Opportunities in Locoregional Therapies

Simple Summary

Pancreatic cancer is a serious ongoing global health burden, with an overall 5-year survival rate of less than 5%. One major hurdle in the treatment of this disease is the predominantly elderly patient population, leading to their ineligibility for curative surgery and a low rate of successful outcomes. Systemic administration introduces chemo-agents throughout the body via the blood, attacking not only tumours but also healthy organs. When localised interventions are employed, chemo-agents are retained specifically at tumour site, minimizing unwanted toxicity. As a result, there is a growing interest in finding novel localised interventions as alternatives to systemic therapy. Here, we present a detailed review of current locoregional therapies used in pancreatic cancer therapy. This work aims to present a thorough guide for researchers and clinicians intended to employ established and novel localised interventions in the treatment of pancreatic cancer. Furthermore, we present our insights and opinions on the potential ideals to improve these tools.

Abstract

Pancreatic cancer (PC) remains the seventh leading cause of cancer-related deaths worldwide and the third in the United States, making it one of the most lethal solid malignancies. Unfortunately, the symptoms of this disease are not very apparent despite an increasing incidence rate. Therefore, at the time of diagnosis, 45% of patients have already developed metastatic tumours. Due to the aggressive nature of the pancreatic tumours, local interventions are required in addition to first-line treatments. Locoregional interventions affect a specific area of the pancreas to minimize local tumour recurrence and reduce the side effects on surrounding healthy tissues. However, compared to the number of new studies on systemic therapy, very little research has been conducted on localised interventions for PC. To address this unbalanced focus and to shed light on the tremendous potentials of locoregional therapies, this work will provide a detailed discussion of various localised treatment strategies. Most importantly, to the best of our knowledge, the aspect of localised drug delivery systems used in PC was unprecedentedly discussed in this work. This review is meant for researchers and clinicians considering utilizing local therapy for the effective treatment of PC, providing a thorough guide on recent advancements in research and clinical trials toward locoregional interventions, together with the authors’ insight into their potential improvements.

Current status of non-surgical treatment of locally advanced pancreatic cancer

Pancreatic cancer is the 7th leading cause of death due to cancer in industrialized countries and the 11th most common cancer globally, with 458918 new cases (2.5% of all cancers) and 432242 deaths (4.5% of all cancer deaths) in 2018. Unfortunately, 80% to 90% of the patients present with unresectable disease, and the reported 5-year survival rate range between 10% and 25%, even after successful resection with tumor-free margins. Systemic chemotherapy, radiotherapy, and minimally invasive image-guided procedures that have emerged over the past years, are used for the management of non-operable PC. This review focuses on currently available non-surgical options of locally advanced pancreatic cancer.

Irreversible Electroporation Plus Anti-PD-1 Antibody versus Irreversible Electroporation Alone for Patients with Locally Advanced Pancreatic Cancer

BACKGROUND

Irreversible electroporation (IRE) is shown to not only improve the prognosis of patients with locally advanced pancreatic cancer (LAPC) but also activate the immune system. Considering the immune-activating function of IRE, IRE may enhance the effect of immune checkpoint inhibitors in the treatment of LAPC. We aimed to compare the effect and safety of IRE combined with toripalimab versus IRE alone for LAPC.

METHODS

We retrospectively collected data from LAPC patients treated with IRE plus toripalimab (240mg, 7 days after IRE) or IRE alone at Sun Yat‑sen University Cancer Center. Overall and progression-free survival and treatment-related adverse events were evaluated and compared.

RESULTS

From August 2015 to June 2020, a total of 85 patients were collected and analyzed in this study: 70 in the IRE group and 15 in the IRE plus toripalimab group. The IRE plus toripalimab group showed longer OS [44.33 months (95% CI 17.39-71.27) versus 23.37 months (95% CI 21.20-25.54), P=0.010] and PFS [27.5 months (95% CI not reached) versus 10.6 months (95% CI 7.79-13.42), P=0.036], compared with IRE group. There were no treatment-related deaths in all patients of this study. Although pancreatic fistula, biliary fistula, abscess, vomiting and gastroparesis were a little more common in IRE plus toripalimab group, no significant differences in the rates of all adverse events between these two groups were observed.

CONCLUSION

IRE plus toripalimab had acceptable toxic effects and might improve survival in LAPC compared with IRE alone.