Case report: Irreversible electroporation for locally advanced pancreatic cancer

Development of a thermal model for irreversible electroporation: an approach to estimate and optimize the IRE protocols

Purpose

Irreversible electroporation (IRE) is an emerging technique that has drawn attention in the field of cancer treatment. IRE uses non-thermal electric pulses to induce death of cancerous cells. However, recent studies have shown that the application of this technique may result in heating of the tissue. There is still room for improving its efficiency and defining better treatment protocols. This study investigates the optimal IRE protocols that avoiding the thermal damage during the IRE treatment.

Methods

Electrode and pulse parameter are investigated. Finite element models are created to evaluate the ablation area and the temperature changes in the tissue. The model is validated experimentally in bovine liver tissue, while the parameters were optimized using response surface method (RSM).

Results

From analysis of variance, the parameter of electrode distance and input voltage has significant effect to the temperature rise in the IRE treatment of bovine liver (P = 0.020 and P = 0.003 respectively). Meanwhile, only the input voltage significantly affects the ablation area (P < 0.001). The optimal result from RSM showed that for maximum ablation area 250.82mm² with no thermal damage, the IRE protocol consisted of an active electrode length of 10 mm, a distance between electrodes of 10 mm, and the delivery of 50 pulses of 41.21 µs and 3000 V.

Conclusions

The approach presented in this study allows the optimization of the IRE protocols. An optimal IRE protocol that maximizes the ablation area was successfully calculated which can be applied with no risk of thermal damage to the tissue.

Benefit from the inclusion of surgery in the treatment of patients with stage III pancreatic cancer: a propensity-adjusted, population-based SEER analysis

Purpose

In the past 20 years, surgical resection has been a secure and applicable procedure for pancreatic cancer (PC), but it remains controversial for stage III PC with data evaluating its efficacy mostly derived from small randomized trials. Hence, we designed this study to further evaluate its benefit using surveillance, epidemiology, and end results dataset.

Patients and methods

Patients with stage III PC were identified in the surveillance, epidemiology, and end results registries from 2004 to 2014. The effect of surgery on cancer-specific survival was assessed by risk-adjusted Cox proportional hazard regression modeling and propensity score matching.

Results

Overall, 6,138 patients with stage III PC were included. Of these, 608 patients underwent primary tumor surgery. On multivariable analyses, surgery was independently associated with improved cancer-specific survival (HR=0.580; 95% CI=0.523–0.643, p<0.001). The survival benefit with surgery was also observed in the propensity score-matched cohort (HR=0.501; 95% CI=0.438–0.573, p<0.001).

Conclusion

Primary tumor surgery is associated with improved survival in stage III PC. Prospective randomized trials are needed to confirm these results, and further efforts are required to address patient selection.

Irreversible electroporation of locally advanced solid pseudopapillary carcinoma of the pancreas: A case report

Introduction

Solid pseudopapillary Carcinoma (SPC) is a rare pancreatic Tumor with variable, usually low, malignancy potential. Howewer, several SPC are associated with aggressive behavior, local vascular infiltration, organ invasion, distant metastasis, and can be unresectable. Irreversible Electroporation (IRE) is an emerging non-thermal ablation technique for the treatment of locally advanced pancreatic carcinoma. We report the results of four year disease-free follow-up in a case of locally advanced unresectable SPC treated with IRE.

Presentation of case

A 24-year female patient with SPC of the pancreas underwent IRE during laparotomy under general anesthesia with intubation. Computed Tomography (CT) showed complete tumor thrombosis of splenic vein, encasement of celiac artery and mesenteric vein. Six insertions of 3–4 electrodes per insertion were performed. One month-CT-control showed shrinkage of the tumor. 6 months-post-treatment imaging showed complete regression of the mass, patent Splenic/mesenteric veins, absence of local recurrence or distant metastasis. Post treatment CTs at 12-18-24-30-36-42-48 months follow-up confirmed absence of local or distant recurrence.

Discussion

Surgery is the first choice curative treatment of SPC. Howewer aggressive surgery (duodeno-pancreasectomy) in unresectable cases, may have a high risk of recurrences, morbidities and death, and bring concerns about endocrine and exocrine insufficiency in a young patient. In these cases, IRE could be a safe and effective alternative treatment and could realize, in selected cases, the condition for a radical surgery, and a bridge to R-0 resection.

Conclusions

IRE could represent an effective alternative therapy to surgery in local advanced, unresectable SPC.

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Solid pseudopapillary Carcinoma (SPC) is a rare pancreatic Tumor with possible local vascular infiltration, distant metastasis, and can be unresectable.

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Irreversible Electroporation (IRE) is a non-thermal ablation technique for locally advanced pancreatic neoplasms.

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There is no case of SPC treated with IRE reported in the literature.

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IRE could be a safe and effective alternative treatment and could be a bridge to R-0 resection.