Gemcitabine plus concurrent irreversible electroporation vs gemcitabine alone for locally advanced pancreatic cancer

MRI-guided stereotactic ablative body radiotherapy versus CT-guided percutaneous irreversible electroporation for locally advanced pancreatic cancer (CROSSFIRE): a single-centre, open-label, randomised phase 2 trial

BACKGROUND

Pancreatic ductal adenocarcinoma is an aggressive disease with a dismal prognosis. Stage III locally advanced pancreatic cancer is considered unresectable and current palliative chemotherapy regimens only modestly improve survival. Guidelines suggest chemoradiation or stereotactic ablative body radiotherapy (SABR) could be beneficial in certain circumstances. Other local treatments such as irreversible electroporation could enhance patient outcomes by extending survival while preserving quality of life. We aimed to compare the efficacy and safety of MRI-guided SABR versus CT-guided percutaneous irreversible electroporation following standard FOLFIRINOX chemotherapy.

METHODS

CROSSFIRE was an open-label, randomised phase 2 superiority trial conducted at the Amsterdam University Medical Centre (Amsterdam, Netherlands). Eligible patients were aged 18 years or older with confirmed histological and radiological stage III locally advanced pancreatic cancer. The maximum tumour diameter was 5 cm and patients had to be pretreated with three to eight cycles of FOLFIRINOX. Patients were randomly assigned (1:1) to MRI-guided SABR (five fractions of 8 Gy delivered on non-consecutive days) or CT-guided percutaneous irreversible electroporation using a computer-generated variable block randomisation model. The primary endpoint was overall survival from randomisation, assessed in the intention-to-treat population. Safety was assessed in the per-protocol population. A prespecified interim futility analysis was done after inclusion of half the original sample size, with a conditional probability of less than 0·2 resulting in halting of the study. The trial was registered at ClinicalTrials.gov, NCT02791503.

FINDINGS

Between May 1, 2016, and March 31, 2022, 68 patients were enrolled and randomly assigned to SABR (n=34) or irreversible electroporation (n=34), of whom 64 were treated according to protocol. Of the 68 participants, 36 (53%) were male and 32 (47%) were female, with a median age of 65 years (IQR 57-70). Median overall survival from randomisation was 16·1 months (95% CI 12·1-19·4) in the SABR group versus 12·5 months (10·9-17·0) in the irreversible electroporation group (hazard ratio [HR] 1·39 [95% CI 0·84-2·30]; p=0·21). The conditional probability to demonstrate superiority of either technique was 0·13; patient accrual was therefore stopped early for futility. 20 (63%) of 32 patients in the SABR group versus 19 (59%) of 32 patients in the irreversible electroporation group had adverse events (p=0·8) and five (16%) patients in the SABR group versus eight (25%) in the irreversible electroporation group had grade 3-5 adverse events (p=0·35). The most common grade 3-4 adverse events were cholangitis (two [6%] in the SABR group vs one [3%] in the irreversible electroporation group), abdominal pain (one [3%] vs two [6%]), and pancreatitis (none vs two [6%]). One (3%) patient in the SABR group and one (3%) in the irreversible electroporation group died from a treatment-related adverse event.

INTERPRETATION

CROSSFIRE did not identify a difference in overall survival or incidence of adverse events between MRI-guided SABR and CT-guided percutaneous irreversible electroporation after FOLFIRINOX. Future studies should further assess the added value of local ablative treatment over chemotherapy alone.

FUNDING

Adessium Foundation, AngioDynamics.

Irreversible electroporation combined with chemotherapy and PD-1/PD-L1 blockade enhanced antitumor immunity for locally advanced pancreatic cancer

Background

Irreversible electroporation (IRE) is a novel local tumor ablation approach with the potential to stimulate an antitumor immune response. However, it is not effective in preventing distant metastasis in isolation. This study aimed to compare the potential of augmenting the antitumor immune response in patients with locally advanced pancreatic cancer (LAPC) who underwent IRE combined with chemotherapy and PD-1/PD-L1 blockade with those who underwent IRE combined with chemotherapy.

Methods

A retrospective review was conducted on LAPC patients treated either with IRE in combination with chemotherapy and PD-1/PD-L1 blockade (group A) or with IRE with chemotherapy alone (group B) from July 2015 to June 2021. The primary outcomes were overall survival (OS) and progression-free survival (PFS), with immune responses and adverse events serving as secondary endpoints. Risk factors for OS and PFS were identified using univariate and multivariate analyses.

Results

A total of 103 patients were included in the final analysis, comprising 25 in group A and 78 in group B. The median duration of follow-up was 18.2 months (3.0-38.6 months). Group A patients demonstrated improved survival compared to group B (median OS: 23.6 vs. 19.4 months, p = 0.001; median PFS: 18.2 vs. 14.7 months, p = 0.022). The data suggest a robust immune response in group A, while adverse events related to the treatment were similar in both groups. The multivariate analysis identified the combination of IRE, chemotherapy, and PD-1/PD-L1 blockade as an independent prognostic factor for OS and PFS.

Conclusion

The addition of PD-1/PD-L1 blockade to the regimen of IRE combined with chemotherapy enhanced antitumor immunity and extended survival in LAPC patients.

Irreversible Electroporation in Pancreatic Cancer-An Evolving Experimental and Clinical Method

Pancreatic cancer has no symptoms until the disease has advanced and is aggressive cancer with early metastasis. Up to now, the only curative treatment is surgical resection, which is possible in the early stages of the disease. Irreversible electroporation treatment offers new hope for patients with unresectable tumors. Irreversible electroporation (IRE) is a type of ablation therapy that has been explored as a potential treatment for pancreatic cancer. Ablation therapies involve the use of energy to destroy or damage cancer cells. IRE involves using high-voltage, low-energy electrical pulses to create resealing in the cell membrane, causing the cell to die. This review summarizes experiential and clinical findings in terms of the IRE applications. As was described, IRE can be a non-pharmacological approach (electroporation) or combined with anticancer drugs or standard treatment methods. The efficacy of irreversible electroporation (IRE) in eliminating pancreatic cancer cells has been demonstrated through both in vitro and in vivo studies, and it has been shown to induce an immune response. Nevertheless, further investigation is required to assess its effectiveness in human subjects and to comprehensively understand IRE's potential as a treatment option for pancreatic cancer.

Simultaneous Gemcitabine and Percutaneous CT-Guided Irreversible Electroporation for Locally Advanced Pancreatic Cancer

Background

Irreversible electroporation (IRE) is a new local ablation technique for pancreatic cancer. The aim of this study is to analyse the safety and effectiveness of simultaneous gemcitabine and percutaneous CT-guided IRE for locally advanced pancreatic cancer (LAPC).

Materials and Methods

From October 2016 to January 2018, 61 patients with LAPC who received simultaneous gemcitabine and IRE therapy (GEM-IRE group, n = 31) or IRE alone therapy (IRE group, n = 30). Routine intravenous gemcitabine chemotherapy was performed 2 weeks after IRE in both groups.

Results

Technical success rates were 90.0% (27/30) and 93.3% (28/30) in the GEM-IRE and IRE groups. Compared with the IRE group, the GEM-IRE group exhibited longer overall survival (OS), local tumor progression free survival (LTPFS), and distant disease free survival (DDFS) from IRE (OS, 17.1 vs. 14.2 months, p=0.031; LTPFS, 14.6 vs. 10.2 months, p=0.045; DDFS, 15.4 vs. 11.7 months, p=0.071). Multivariate Cox regression analysis results suggested that tumor volume ≤37 cm³ and simultaneous gemcitabine with IRE were significant independent prognostic factors of OS, LTPFS, and DDFS. Four major adverse reactions occurred; all of them were resolved after symptomatic treatment.

Conclusions

Simultaneous gemcitabine and percutaneous CT-guided IRE therapy model was effective and well-tolerated therapeutic strategy in LAPC patients.

Treatment of unresectable locally advanced pancreatic cancer with percutaneous irreversible electroporation (IRE) following initial systemic chemotherapy (LAP-PIE) trial: study protocol for a feasibility randomised controlled trial

BACKGROUND

Approximately 30% of patients with pancreas cancer have unresectable locally advanced disease, which is currently treated with systemic chemotherapy. A new treatment option of irreversible electroporation (IRE) has been investigated for these patients since 2005. Cohort studies suggest that IRE confers a survival advantage, but with associated, procedure-related complications. Selection bias may account for improved survival and there have been no prospective randomised trials evaluating the harms and benefits of therapy. The aim of this trial is to evaluate the feasibility of a randomised comparison of IRE therapy with chemotherapy versus chemotherapy alone in patients with locally advanced pancreatic cancer (LAPC).

METHODS AND ANALYSIS

Eligible patients with LAPC who have undergone first-line 5-FluoroUracil, Leucovorin, Irinotecan and Oxaliplatin chemotherapy will be randomised to receive either a single session of IRE followed by (if indicated) further chemotherapy or to chemotherapy alone (standard of care). Fifty patients from up to seven specialist pancreas centres in the UK will be recruited over a period of 15 months. Trial follow-up will be 12 months. The primary outcome measure is ability to recruit. Secondary objectives include practicality and technical success of treatment, acceptability of treatment to patients and clinicians and safety of treatment. A qualitative study has been incorporated to evaluate the patient and clinician perspective of the locally advanced pancreatic cancer with percutaneous irreversible electroporation trial. It is likely that the data obtained will guide the structure, the primary outcome measure, the power and the duration of a subsequent multicentre randomised controlled trial aimed at establishing the clinical efficiency of pancreas IRE therapy. Indicative procedure-related costings will be collected in this feasibility trial, which will inform the cost evaluation in the subsequent study on efficiency.

ETHICS AND DISSEMINATION

The protocol has received approval by London-Brent Research Ethics Committee reference number 21/LO/0077.Results will be analysed following completion of trial recruitment and follow-up. Results will be presented to international conferences with an interest in oncology, hepatopancreaticobiliary surgery and interventional radiology and be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ISRCTN14986389.

Locoregional therapies and their effects on the tumoral microenvironment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is expected to become the second leading cause of death from cancer by 2030. Despite intensive research in the field of therapeutics, the 5-year overall survival is approximately 8%, with only 20% of patients eligible for surgery at the time of diagnosis. The tumoral microenvironment (TME) of the PDAC is one of the main causes for resistance to antitumoral treatments due to the presence of tumor vasculature, stroma, and a modified immune response. The TME of PDAC is characterized by high stiffness due to fibrosis, with hypo microvascular perfusion, along with an immunosuppressive environment that constitutes a barrier to effective antitumoral treatment. While systemic therapies often produce severe side effects that can alter patients' quality of life, locoregional therapies have gained attention since their action is localized to the pancreas and can thus alleviate some of the barriers to effective antitumoral treatment due to their physical effects. Local hyperthermia using radiofrequency ablation and radiation therapy - most commonly using a local high single dose - are the two main modalities holding promise for clinical efficacy. Recently, irreversible electroporation and focused ultrasound-derived cavitation have gained increasing attention. To date, most of the data are limited to preclinical studies, but ongoing clinical trials may help better define the role of these locoregional therapies in the management of PDAC patients.

Minimally invasive image-guided therapy of primary and metastatic pancreatic cancer

Pancreatic cancer is a challenging malignancy with limited treatment options and poor life expectancy. The only curative option is surgical resection, but only 15%-20% of patients are resectable at presentation because more than 50% of patients has distant metastasis at diagnosis and the rest of them has locally advanced pancreatic cancer (LAPC). The standard of care first line treatment for LAPC patients is chemotherapy with or without radiation therapy. Recent developments in minimally invasive ablative techniques may add to the treatment armamentarium of LAPC. There are increasing number of studies evaluating these novel ablative techniques, including radiofrequency ablation, microwave ablation, cryoablation and irreversible electroporation. Most studies which included pancreatic tumor ablation, demonstrated improved overall survival in LAPC patients. However, the exact protocols are yet to set up to which stage of the treatment algorithm ablative techniques can be added and in what kind of treatment combinations. Patients with metastatic pancreatic cancer has dismal prognosis with 5-year survival is only 3%. The most common metastatic site is the liver as 90% of pancreatic cancer patients develop liver metastasis. Chemotherapy is the primary treatment option for patients with metastatic pancreatic cancer. However, when the tumor is not responding to chemotherapy or severe drug toxicity develops, locoregional liver-directed therapies can provide an opportunity to control intrahepatic disease progression and improve survival in selected patients. During the last decade new therapeutic options arose with the advancement of minimally invasive technologies to treat pancreatic cancer patients. These new therapies have been a topic of increasing interest due to the severe prognostic implications of locally advanced and metastatic pancreatic cancer and the low comorbid risk of these procedures. This review summarizes new ablative options for patients with LAPC and percutaneous liver-directed therapies for patients with liver-dominant metastatic disease.