## 4 Discussion  
The use of electroablation for nonresectable pancreatic tumors is controversial, and the largest groups of patients include 200-300 individuals. Patients qualified for ablation are most often treated with CTH, which impedes the determination of the effectiveness of IRE alone. However, for patients with nonresectable pancreatic cancers, electroablation often remains the last treatment option, and at this stage of cancer, every attempt to extend life expectancy or, at least, improve the quality of life (for example, by decreasing pain) seems legitimate. Here, we have presented two cases: the IRE method was combined with calcium chloride as a cytostatic drug. Irreversible and reversible electroporation occurs simultaneously during the procedure, and it is impossible to know the range of each. There are some simulation and predictive studies estimating the IRE range [53; 54]. Thus, the application of chemotherapeutic agent seems reasonable. In the first case, changes in the tissue conductivity were observed with the intratumoral administration \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Case 1** & **Case 2** \\ \hline Progression/regression/stabilization in CT & stabilization & stabilization \\ after 3 months according to RECIST criteria & & \\ \hline Ca 19-9 [U/mL] after 3 months & 408 & 35.46 \\ \hline Continuation of chemotherapy & Yes & Yes \\ \hline Weight & 75 kg & 68 kg after 3 months 77 kg now \\ \hline Pain in VAS scale & 8 & 0 \\ \hline Overall survival & 9 months & 21 months and counting \\ \hline Survival after electroporation procedure & 6 months & 12 months and counting \\ \hline \hline \end{tabular} RECIST: response evaluation criteria in solid tumors.  
\end{table} 
Table 3: Patient comparison 3 months post treatment. of calcium ions before the IRE procedure. This required an adjustment of the device and the application of lower voltage doses. Immediately after the procedure, the patient developed acute pancreatitis. The patient was hospitalized for a longer period of time, and the complication, namely pancreatic fistula, persisted up to one month after the procedure, delaying chemotherapeutic treatment according to the protocol. The patient lost weight and experienced significantly more severe pain related to the complication. Two months after the procedure, the patient was feeling fine; there was no impairment of food intake and no further weight loss. The patient qualified for systemic treatment, which was inefficient, and the patient died 9 months after diagnosis. In the second case, IRE was conducted with intraoperative chemotherapy and calcium electroporation, which was administered after the ablative procedure. The patient recovered well, developed pancreatic fistula with low secretion, which did not require any treatment, and his chemotherapy protocol was continued. After three months of observation, the patient did not feel any pain; hence, neuolysis during the ablative procedure might have occurred. The patient discontinued opioid treatment, gained weight, and is still alive 21 months after a pancreatic cancer diagnosis. Currently, there are no standards for combining IRE or ECT with chemotherapeutic treatment protocols for pancreatic tumors. The present clinical data indicate a positive effect of IRE alone in pancreatic cancer [52], including LAPC [55]. Clinical trials in which pancreatic ductal adenocarcinoma (PDAC) was treated by IRE combined with anti-programmed cell death protein 1 (anti-PD1) have shown promising results [56]. However, to date, our study is the first one in which the IRE method was combined with intratumoral administration of the calcium ions. Although the question of whether IRE alone should be applied as a palliative method has been responded to positively, the appropriate positioning of IRE application remains to be clarified.