Electrochemotherapy Research Articles

Electrochemotherapy in locally advanced pancreatic cancer: Preliminary results

ObjectiveReport the preliminary results on electrochemotherapy (ECT) in the treatment of locally advanced pancreatic cancer of a phase I/II study and described the new functional imaging tools to assess ECT response in Magnetic Resonance (MR) imaging compared to morphological Computer Tomography (CT), ultrasound (US) without and with contrast enhancement (CEUS) and MR Imaging. Materials and methodsThirteen patients were enrolled in an ongoing clinical phase I/II study approved by Ethical Committee of National Cancer Institute G. Pascale Foundation – IRCCS of Naples. ECT with bleomycin was performed during open surgery. All patients underwent US and CT scan, before and after ECT treatment; 7 patients were evaluated using morphological and functional (dynamic contrast enhancement-DCE and diffusion weighted- DW) parameters in MR; 5 patients underwent CEUS. RECIST criteria were used to evaluate ECT response on US, CT and MR images. Functional parameters were also used to evaluate ECT response on MR images. ResultsNo acute (intraoperative) and/or postoperative serious adverse events related to electrochemotherapy were observed; no clinically significant electrocardiographic, hemodynamic, or serum biologic changes were noted. No clinically relevant elevation of amylase or lipase levels was observed and no bleeding or damage to surrounding viscera occurred. In three patients had seen splenic infarction without thrombosis of the splenic vessels. ConclusionElectrochemotherapy is feasible and safe treatment modality in patients with locally advanced pancreatic adenocarcinoma. Dynamic and diffusion MR imaging in comparison to MR morphological sequence alone and to UC and CT imaging is more suitable to assess ECT treatment response. CEUS is not indicated in follow up after ECT.

Feasibility and safety of electrochemotherapy (ECT) in the pancreas: a pre-clinical investigation.

Background.Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease generally refractory to standard chemotherapeutic agents; therefore improvements in anticancer therapies are mandatory. A major determinant of therapeutic resistance in PDAC is the poor drug delivery to neoplastic cells, mainly due to an extensive fibrotic reaction. Electroporation can be used in vivo to increase cancer cells’ local uptake of chemotherapeutics (electrochemotherapy, ECT), thus leading to an enhanced tumour response rate. In the present study, we evaluated the in vivo effects of reversible electroporation in normal pancreas in a rabbit experimental model. We also tested the effect of electroporation on pancreatic cancer cell lines in order to evaluate their increased sensitivity to chemotherapeutic agents.Materials and methods.The application in vivo of the European Standard Operating Procedure of Electrochemotherapy (ESOPE) pulse protocol (1000 V/cm, 8 pulses, 100 μs, 5 KHz) was tested on the pancreas of normal New Zealand White Rabbits and short and long-term toxicity were assessed. PANC1 and MiaPaCa2 cell lines were tested for in vitro electrochemotherapy experiments with and without electroporation. Levels of cell permeabilization were determined by flow cytometry, whereas cell viability and drug (cisplatin and bleomycin) sensitivity of pulsed cells were measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay.Results.In healthy rabbits, neither systemic nor local toxic effects due to the electroporation procedure were observed, demonstrating the safety of the optimized electric parameters in the treatment of the pancreas in vivo. In parallel, we established an optimized protocol for ECT in vitro that determined an enhanced anti-cancer effect of bleomycin and cisplatin with respect to treatment without electroporation.Conclusions.Our data suggest that electroporation is a safe procedure in the treatment of PDAC because it does not affect normal pancreatic parenchyma, but has a potentiating effect on cytotoxicity of bleomycin in pancreatic tumour cell lines. Therefore, ECT could be considered as a valid alternative for the local control of non-resectable pancreatic cancer.

Low immunogenicity in non-small cell lung cancer; do new developments and novel treatments have a role?

Approximately 1.6 million new cases of lung cancer are diagnosed annually (Jemal et al. CA: A Cancer Journal for Clinicians, 61, 69-90, 2011) and it remains the leading cause of cancer-related mortality worldwide. Despite decades of bench and clinical research to attempt to improve outcome for locally advanced, good performance status patients, the 5-year survival remains less than 15% (Molina et al. 2008). Immune checkpoint inhibitor (ICH) therapies have shown a significant promise in preclinical and clinical trails to date in the treatment of non-small cell lung cancer (NSCLC). The idea of combining these systemic immune therapies with local ablative techniques is one that is gaining momentum. Electrochemotherapy (ECT) is a unique atraumatic local therapy that has had very promising objective response rates and a number of advantages including but not limited to its immunostimulatory effects. ECT in combination with ICHs offers a novel approach for dealing with this difficult disease process.

Surgery and electrochemotherapy for the treatment of cutaneous squamous cell carcinoma in a yellow-bellied slider (Trachemys scripta scripta)

A 5-year-old female yellow-bellied slider (Trachemys scripta scripta) was referred for evaluation of a 2-month nonhealing ulcerated mass on the dorsal aspect of the neck. The turtle was quiet, alert, and responsive, with a 2 × 1.5-cm ulcerated lesion on the neck. Signs of discomfort were observed during manipulation of the neck; no other abnormalities were detected during physical evaluation. Following total body radiography and hematologic and serum biochemical analysis, the turtle was anesthetized and the mass was surgically removed. The excised tissue was submitted for histologic evaluation. A histopathologic diagnosis of squamous cell carcinoma (SCC) was made. Further surgical revision was not an option because of the extensive nature of the lesion; therefore, the tumor bed was treated with electrochemotherapy (ECT). Two sessions of ECT were performed with a 2-week interval between treatments. Electrochemotherapy involved intratumoral administration of bleomycin followed by trains of biphasic electric pulses. The treatment was well tolerated, and the turtle was disease free after 12 months. ECT resulted in good local control of SCC and should be considered as a possible postsurgical adjuvant treatment in reptiles with cutaneous tumors.

Electrochemotherapy – possible benefits and limitations to its use in the head and neck region

Conclusion: Electrochemotherapy (ECT) is an efficacious treatment. It should, however, be used with some caution in the treatment of head and neck cancer. Objectives: To assess local tumor control, safety, survival, and functional outcome after treatment of cancer in the head and neck region with ECT. Methods: Four patients with primary T2 cancer of the oral cavity or oropharynx and one patient with a metastasis of renal cancer in the masseter muscle were treated with ECT with intratumorally administered bleomycin. Control biopsies were carried out 2 months after treatment. Postoperative radiotherapy was performed based on tumor T-stage and the depth of tumor infiltration. Serious adverse events and treatment malfunctions were recorded. The follow-up time was 24 months for the surviving patients and 20 months overall. The PSS-HN scale was used to assess the functional outcome. Results: No local recurrence was recorded in any patient during the follow-up. However, only one patient was treated with ECT alone. There were four serious adverse events: one nearly lethal bleeding, two cases of osteoradionecrosis, and a fistula. One patient died from distant metastasis. The other patients were tumor-free both locally and overall at 24 months. The median functional outcome in all parameters was worse 1 year after treatment.

HF ultrasound vs PET-CT and telethermography in the diagnosis of In-transit metastases from melanoma: a prospective study and review of the literature.

BackgroundOver the past several years the incidence of cutaneous melanoma has rapidly increased. This tumor develops often in-transit metastases that significantly reduce patient survival at 5 years. To improve prognosis and quality of life in patients with melanoma metastases, a mini invasive procedure like electrochemotherapy (ECT) is adopted to remove superficial tissue lesions. To detect the melanoma metastases, high frequency (HF) ultrasound (US) is used. This technique, though, can be time-consuming and it needs an expert operator and a high performing machine. Therefore, we asked whether the US could be replaced or integrated with other less time-consuming techniques such as 18-FDG positron emission tomography/computed tomography (PET-CT) and telethermography (TT).MethodsFifteen patients (4 males and 11 females - age range: 63–91) affected whit advanced stage melanoma were enrolled. They presented 52 in-transit metastases as detected by the three techniques used, HF-US, PET/CT and TT within 30 days before ECT.ResultsAll the 52 lesions were detected by HF-US (100%), 24/52 were detected by PET-CT (42,6%) and 15/52 were detected by TT (27,7%). PET-CT reported 3.7% false positives, while no false positive were reported by TT.ConclusionsAs US detected 100% lesions, compared to the other two techniques used, US, along with clinical examination, has still to be considered as gold standard in the diagnosis of metastatic lesions. US, associated with an exhaustive anamnesis and accurate clinical examination, cannot be replaced by either PET-CT or TT. When US performing devices and experienced operators are not available, though, it is highly recommended to integrate US with at least one of the other techniques. Under certain circumstances, as in the case of obese and non-collaborating patients or in patients with lymphatic stasis, these techniques should be integrated to obtain exact in-transit metastases evaluation.

The photodynamic effect of far-red range phthalocyanines (AlPc and Pc green) supported by electropermeabilization in human gastric adenocarcinoma cells of sensitive and resistant type

IntroductionElectroporation (EP) is commonly applied for effective drug transport thorough cell membranes based on the application of electromagnetic field. When applied with cytostatics, it is called electrochemotherapy (ECT) – a quite new method of cancer treatment. A high-voltage pulse causes the formation of temporary pores in the cell membrane which create an additional way for the intracellular drug transport. In the current work, EP was effectively merged with the already known photodynamic therapy (PDT) to selective photosensitizers’ delivery to diseased tissue. The application of electroporation can reduce the dose of applied drug. Research objectiveThe aim of research was to evaluate the effectiveness of photodynamic reaction using two near infrared cyanines (AlPc and Pc green) combined with electroporation in two human gastric adenocarcinoma cell lines. Materials and methodsTwo human cell lines – EPG85-257P (parental) and EPG85-257RDB (resistant to daunorubicin) – of gastric cancer were used. The effect of two photosensitizers (aluminum 1,8,15,22-tetrakis(-phenylthio)-29H,31H-phthalocyanine chloride and Phthalocyanine green) was investigated. The efficiency of EP parameters was assessed by propidium iodide uptake. The viability assay was applied to analyse EP, PDT and EP-PDT effect. Cyanine localization was determined by confocal microscopy. Immunocytochemical evaluation of manganese superoxide dismutase and glutathione S-transferase-pi was determined after applied therapies. ResultsPDT in combination with EP affected the viability of EPG85-257P and EPG85-257RDB cells negatively while both cyanine were used. The most evident changes were observed in the following concentrations: 15, 10 and 5μM. The optimal field strength for enhanced EP-PDT was 800 and 1200V/cm. AlPc distributed selectively in the lysosomes of parental cell line. ConclusionsPDT, enhanced by EP, caused decreased viability when compared to the application of PDT alone. Both phthalocyanines found to be more effective after electroporation. Due to the low concentration of light-sensitive compounds and safety of electroporation itself, a treatment plan can be an alternative therapeutic modality against gastric adenocarcinomas.

The Use of Electrochemotherapy as Neoadjuvant Treatment for Head and Neck Cancer

Objectives: Electrochemotherapy (ECT) is a cancer treatment based on the transport of chemotherapic drugs such as cisplatin and bleomycin into cell cytosol through depolarization of cell membrane. A locally applied electric field modifies the membrane permeability allowing intracellular accumulation of the chemotherapeutic agent. Methods: Prospective study: 12 patients with head and neck cancer treated with ECT with bleomycin at the ENT Department of Catanzaro teaching hospital from January to December 2013 were recruited. The primary endpoint of the study was ECT efficacy in the neoadjuvant treatment of head and neck cancer. For each patient clinical-anamnestic data were collected in a database and the local tumor control, survival, and effects on quality of life (Health Survey Questionnaire, SF-36 [v1], and Quality of Life Questionnaire, EORTC QLQ-C30, and EORTC QLQH&N35) and pain control (Analgesia Post-Surgery, APS scale) were evaluated. The treatments were performed by Cliniporator IGEA according to the European Standard Operating Procedures of Electrochemotherapy (ESOPE, 2006). Response to ECT treatment was evaluated after 30 days. All patients received postoperative chemoradiotherapy. Results: Local control and impact on quality of life were evaluated. Six of 12 lesions exhibited a partial response, 4 of 12 exhibited a complete response, and in 2 cases disease progression was observed. Conclusions: ECT represents a safe and effective therapeutic approach that is associated with clear benefits in terms of quality of life (minimal discomfort, mild post-treatment pain, and short duration of hospital stay).

Phase I/II Study of Electrochemotherapy with Intravenous Bleomycin and Variable Geometry Electric Fields for the Treatment of Deep and Large Soft Tissue Tumors

ABSTRACT Background: Background: electroporation, an effective drug delivery system, enhances the uptake of chemotherapeutic agents by means of short electrical fields which open transient pores on the cell membrane. Electrochemotherapy (ECT) has proven to be an effective local therapy for patients with superficial (i.e., cutaneous and subcutaneous), small-size metastases. The development of new equipments (i.e., dedicated electrodes and pulse generators) could allow for the electroporation of more challenging tumors. The aim of this study was to assess the feasibility and safety of ECT performed by means of new, 20-cm long, freely-implantable needle electrodes. Further outcome measures were tumor response, response duration and toxicity. This preliminary report is based on the outcome of the first 24 patients (out of the 38 planned) . Methods: a phase I/II study enrolling patients with deep (max 20 cm) and / or large (max 6 cm) unresectable soft tissue metastases which were unresponsive to chemotherapy or radiation. The needle electrodes were inserted percutaneously under US or CT guidance. Their number and disposition was chosen according to a pre-treatment planning based on radiological imaging. Chemotherapy consisted of a bleomycin bolus, followed by the application of electric voltages according to the European Standard Operative Procedures of Electrochemotherapy (ESOPE). Results: out of 24 patients, tumor histotypes were as follows: melanoma, n=10; soft tissue sarcomas, n=10, others, n=4. The electric pulses were successfully applied to all patients, the median time of the procedure being 35 min (range, 20-75). No serious adverse event were reported during hospital stay, which lasted on average 1 day (range, 1-3). Soft tissue toxicity was mild and all patients were followed on an outpatient basis. Among the melanoma patients, local response rate was 100% (complete, 40%), in patients with soft tissue sarcomas local response rate was 90% (complete, 30%). The remaining 4 patients achieved a partial response. Overall, the median local progression-free survival was 13.1 months (range, 3-24). Conclusions: thanks to recent technological advances (i.e., variable geometry electric pulse generators and long needle electrodes) ECT may be successfully applied also to deep-seated and large soft tissue tumors. Trial design: Phase I/II study Disclosure: All authors have declared no conflicts of interest.

Feasibility and Safety of Intraoperative Electrochemotherapy in Locally Advanced Pancreatic Tumor: A Preliminary Experience

Electrochemotherapy is an effective treatment for various cutaneous tumors and could be translated into treatment of deep-seated tumors. With this aim, a prospective clinical phase I/II study was conducted to evaluate the feasibility and safety of intraoperative Electrochemotherapy (ECT) in locally advanced pancreatic adenocarcinoma: the preliminary results are reported in this study. The secondary endpoint was to assess treatment response in terms of morphological and functional criteria based on Magnetic Resonance Imaging. Eleven consecutive patients were enrolled in a clinical phase I/II study approved by the Ethics Committee of the National Cancer Institute G. Pascale Foundation - IRCCS of Naples. Electrochemotherapy with bleomycin was performed during open surgery. All patients underwent MR and CT scan, before and after ECT treatment, using morphological and functional imaging. RECIST criteria were used to evaluate ECT response on CT and MR images. Functional parameters were also used to evaluate ECT response on MR images. No acute (intraoperative) and/or postoperative serious adverse events related to electrochemotherapy were observed; no clinically significant electrocardiographic, hemodynamic, or serum biologic changes were noted. No clinically relevant elevation of amylase or lipase levels was observed and no bleeding or damage to surrounding viscera occurred. Electrochemotherapy of locally advanced pancreatic adenocarcinoma proved to be a feasible and safe treatment modality. Dynamic and diffusion MR imaging is more suitable to assess ECT treatment response than CT imaging and morphological MR alone, after one month of treatment.

A numerical investigation of the electric and thermal cell kill distributions in electroporation-based therapies in tissue.

Electroporation-based therapies are powerful biotechnological tools for enhancing the delivery of exogeneous agents or killing tissue with pulsed electric fields (PEFs). Electrochemotherapy (ECT) and gene therapy based on gene electrotransfer (EGT) both use reversible electroporation to deliver chemotherapeutics or plasmid DNA into cells, respectively. In both ECT and EGT, the goal is to permeabilize the cell membrane while maintaining high cell viability in order to facilitate drug or gene transport into the cell cytoplasm and induce a therapeutic response. Irreversible electroporation (IRE) results in cell kill due to exposure to PEFs without drugs and is under clinical evaluation for treating otherwise unresectable tumors. These PEF therapies rely mainly on the electric field distributions and do not require changes in tissue temperature for their effectiveness. However, in immediate vicinity of the electrodes the treatment may results in cell kill due to thermal damage because of the inhomogeneous electric field distribution and high current density during the electroporation-based therapies. Therefore, the main objective of this numerical study is to evaluate the influence of pulse number and electrical conductivity in the predicted cell kill zone due to irreversible electroporation and thermal damage. Specifically, we simulated a typical IRE protocol that employs ninety 100-µs PEFs. Our results confirm that it is possible to achieve predominant cell kill due to electroporation if the PEF parameters are chosen carefully. However, if either the pulse number and/or the tissue conductivity are too high, there is also potential to achieve cell kill due to thermal damage in the immediate vicinity of the electrodes. Therefore, it is critical for physicians to be mindful of placement of electrodes with respect to critical tissue structures and treatment parameters in order to maintain the non-thermal benefits of electroporation and prevent unnecessary damage to surrounding healthy tissue, critical vascular structures, and/or adjacent organs.

Modulation of activity of known cytotoxic ruthenium(III) compound (KP418) with hampered transmembrane transport in electrochemotherapy in vitro and in vivo.

To increase electrochemotherapy (ECT) applicability, the effectiveness of new drugs is being tested in combination with electroporation. Among them two ruthenium(III) compounds, (imH)[trans-RuCl4(im)(DMSO-S)] (NAMI-A) and Na[trans-RuCl4(ind)2] (KP1339), proved to possess increased antitumor effectiveness when combined with electroporation. The objective of our experimental work was to determine influence of electroporation on the cytotoxic and antitumor effect of a ruthenium(III) compound with hampered transmembrane transport, (imH)[trans-RuCl4(im)2] (KP418) in vitro and in vivo and to determine changes in metastatic potential of cells after ECT with KP418 in vitro. In addition, platinum compound cisplatin (CDDP) and ruthenium(III) compound NAMI-A were included in the experiments as reference compounds. Our results show that electroporation leads to increased cellular accumulation and cytotoxicity of KP418 in murine melanoma cell lines with low and high metastatic potential, B16-F1 and B16-F10, but not in murine fibrosarcoma cell line SA-1 in vitro which is probably due to variable effectiveness of ECT in different cell lines and tumors. Electroporation does not potentiate the cytotoxicity of KP418 as prominently as the cytotoxicity of CDDP. We also showed that the metastatic potential of cells which survived ECT with KP418 or NAMI-A does not change in vitro: resistance to detachment, invasiveness, and re-adhesion of cells after ECT is not affected. Experiments in murine tumor models B16-F1 and SA-1 showed that ECT with KP418 does not have any antitumor effect while ECT with CDDP induces significant dose-dependent tumor growth delay in the two tumor models used in vivo.

A new grid electrode for electrochemotherapy treatment of large skin tumors

Electrochemotherapy (ECT) is a local anticancer treatment for superficial tumors which involves the administration of a chemotherapeutic drug followed by short, high-voltage pulses. Incipient clinical experience with breast cancer patients are encouraging, with a local complete response rate ranging from 50 to 90%. However, since many patients present with multiple or widespread metastases, ECT, despite its high local antitumor efficacy, need to be applied several times in order to complete treatment delivery or maintain tumor control during the follow-up. In this paper, we propose the prototype of a new grid electrode aimed at the improvement of ECT application. The device is suitable for treating large, tumor-infiltrated skin surfaces as in breast cancer patients with chest wall metastases after mastectomy. According to our tests in different in vitro models, the new device allows to apply the voltage pulses more quickly and homogeneously when compared with standard pulse applicators. This technical advancement holds promise for improving ECT outcome and, hopefully, for sparing a number of patients from the need of multiple treatments.

A new grid electrode for electrochemotherapy treatment of large skin tumors

Electrochemotherapy (ECT) is a local anticancer treatment for superficial tumors which involves the administration of a chemotherapeutic drug followed by short, high-voltage pulses. Incipient clinical experience with breast cancer patients are encouraging, with a local complete response rate ranging from 50 to 90%. However, since many patients present with multiple or widespread metastases, ECT, despite its high local antitumor efficacy, need to be applied several times in order to complete treatment delivery or maintain tumor control during the follow-up. In this paper, we propose the prototype of a new grid electrode aimed at the improvement of ECT application. The device is suitable for treating large, tumor-infiltrated skin surfaces as in breast cancer patients with chest wall metastases after mastectomy. According to our tests in different in vitro models, the new device allows to apply the voltage pulses more quickly and homogeneously when compared with standard pulse applicators. This technical advancement holds promise for improving ECT outcome and, hopefully, for sparing a number of patients from the need of multiple treatments.

Combination of therapy with 5-fluorouracil and cisplatin with electroporation in human ovarian carcinoma model in vitro

High electric field, applied to plasma membrane, affects organization of the lipid molecules, generating transient hydrophilic electropores. The application of the cell membrane electroporation in combination with cytotoxic drugs could increase the drug transport into cells. This approach is known as electrochemotherapy (ECT). Our work shows new data concerning the influence of electrochemical reaction with cisplatin or with 5-fluorouracil (5-FU) on cancer ovarian cells resistant to standard therapy with cisplatin, in comparison to ECT effect on human primary fibroblasts. We investigated the effect of electroporation and electrochemotherapy with 5-FU and cisplatin on human ovarian clear-cell carcinoma cell line (OvBH-1) and epithelial ovarian carcinoma cell line (SKOV-3) – both resistant to cisplatin typically used in ovarian cancers. As control cells, human gingival fibroblasts (HGF's) from primary culture were used. Electropermeabilization efficiency was determined by FACS analysis with iodide propidium. Efficiency of electrochemotherapy was evaluated with viability assay. The cytotoxic effect was dependent on the electroporation parameters and on drug concentration. Electroporation alone only insignificantly decreased cells proliferation in OvBH-1 line; SKOV-3 line was more sensitive to the electrical field. Electrochemotherapy with cisplatin and 5-FU showed promising effects on both ovarian cell lines with recovery of normal cells revealed after 72hours.

Definition of Novel Electrochemotherapy Parameters and Validation of their in Vitro and in Vivo Effectiveness

Electrochemotherapy (ECT) is a cancer therapy that conjugates the administration of a chemotherapy agent to the delivery of permeabilizing pulses released singularly or as bursts. This approach results in higher number of anticancer molecules delivered to their biological targets, but is also associated to undesirable side effects such as pain and muscular contractions. A new electroporator delivering train of eight biphasic pulses at the voltage of 1,300 V/cm lasting 50 + 50 µsec each, with a frequency of 1 Hz, and with 10-µsec interpulse intervals (total treatment time: 870 µsec/cm(2) of treated area) was tested in vitro on the human lung cancer cell line A549 and in vivo, both in mice xenografts and privately owned rabbits with spontaneous tumors. The tumor cell line was treated with electroporation using the new parameters, that showed improved drug efficacy in causing cell death. Mice with chemoresistant xenografts were treated as well with either the new parameters and with a previous protocol, confirming the higher tolerability and efficacy of the novel parameters. Finally, a cohort of six pet rabbits with advanced skin neoplasms were enrolled in a compassionate trial using the new parameters in adjuvant fashion. In terms of efficacy, none of the rabbits experienced tumor recurrence, showing minimal discomfort during the ECT sessions. The data described, demonstrate that the new permeabilizing protocol adopting biphasic electric pulses displays a significant higher efficacy compared to previous ECT treatments and substantial reduction of the associated morbidity.

Bleomycin electrochemotherapy in elderly metastatic breast cancer patients: clinical outcome and management considerations.

To evaluate the efficacy and toxicity of electrochemotherapy (ECT) in elderly metastatic breast cancer (BC) patients. Retrospective analysis of 55 patients with superficial metastases who underwent ECT according to the European Standard Operative Procedures of electrochemotherapy. Treatment schedule consisted of intravenous or intratumoral bleomycin followed by locally delivered electric pulses. Statistical comparisons were performed between two groups: the patients aged <70years (n=27) and those ≥70years (n=28). Treatment outcomes were as follows: complete response (CR) rate, local progression-free survival (LPFS), new lesions-free survival (NLFS), toxicity and patient compliance. Patient groups were comparable for clinical-pathological features, except for the number of comorbidities (P<.001). The median follow-up was 32months (range 6-53). Overall, CR rate was 40% and was significantly higher in elderly patients (57 vs. 26%, P=.023) and in patients with better performance status (PS=0-1, 53 vs. PS=2, 21%, P=.048), although local tumor control showed a trend for lower values (2-year LPFS, 67 vs. 93% among elderly and young patients, respectively; P=.061). Older women seemed less likely to progress outside the ECT field (2-year NLFS, 39 vs. 30%, P=.075), but discontinued treatment more frequently due to impaired performance status (P=.002). Local pain was graded ≥3, according to a 10-point visual analog scale, by 16/28 (57.1%) and 8/28 (28.6%) elderly patients at 4 and 8weeks, respectively. Wound debridement was required in 5/28 (18%) older women, due to G3 skin ulceration. Elderly BC patients are highly responsive to ECT and achieve durable local tumor control. Physicians should be aware of possible debilitating side effects, such as pain and skin toxicity. Performance status and frailty screening could be a helpful addition to improve patient selection.

Long-term response after electrochemotherapy in patients with relapsed or refractory cutaneous melanoma

Background Treatment of early and multiple cutaneous unresectable recurrences is a major therapeutic problem with around 80% of patients relapsing within 5 years [1]. For lesions refractory to elective treatments, electrochemotherapy (ECT) involving electroporation combined with antineoplastic drug treatment appears to be a new potential option [2]. This study was undertaken to analyze the shortand long-term responses of lesions treated with ECT with intravenous injection of bleomycin in melanoma patients with in-transit disease or distant cutaneous metastases.

Electrochemotherapy with bleomycin induces hallmarks of immunogenic cell death in murine colon cancer cells

Electrochemotherapy (ECT) is a local cancer treatment that has been used over the course of more than 2 decades for the removal of cutaneous and subcutaneous tumors. Several lines of evidence support the premise that the immune system is an important factor underlying anticancer treatment efficacy, potentially including patient responses to ECT. The concept of immunogenic cell death (ICD) arose a few years ago, stating that some cancer treatments generate danger-associated molecular patterns (DAMPs) that trigger an adaptive immune response against tumors. Hence, dying cancer cells behave as a therapeutic vaccine, eliciting a cytotoxic immune response against surviving malignant cells. In our study, we sought to evaluate the ability of ECT to generate cancer cell death encompassing the immunostimulatory characteristics of ICD. To this end, we assayed CT26 murine colon cancer cells in vitro in response to either electric pulses (EPs) application only or in combination with the anticancer drug bleomycin (that is ECT) by quantification of calreticulin (CRT) membrane externalization, as well as the liberation of adenosine triphosphate (ATP) and high mobility group box 1 (HMGB1) protein. We show here that cell permeabilizing yet non-lethal electric pulses induce CRT exposure on the cell surface of EP-only treated cancer cells, as well as ATP release. However, the association of electric pulses along with the chemotherapeutic agent bleomycin was mandatory for HMGB1 release coincident with regimen-induced cell death. These data obtained in vitro were then substantiated by vaccination protocols performed in immunocompetent mice, showing that the injection of dying ECT-treated cells elicits an antitumor immune response that prevents the growth of a subsequent administration of viable cancer cells. We also confirmed previous results showing ECT treatment is much more efficient in immunocompetent animals than in immunodeficient ones, causing complete regressions in the former but not in the latter. This supports a central role for immunity in this beneficial outcome. In conclusion, we show that ECT not only possesses an intrinsic cytotoxic property toward cancer cells but also generates a systemic anticancer immune response via the activation of ICD. Hence, ECT may represent an interesting approach to treat solid tumors while preventing recurrence and metastasis, possibly in combination with immunostimulating agents.

Locally enhanced chemotherapy by electroporation: clinical experiences and perspective of use of electrochemotherapy.

Electroporation is used to enhance drug diffusion and gene delivery into the cytosol. The combination of electroporation and cytotoxic drugs, electrochemotherapy (ECT), is used to treat metastatic tumor nodules located at the skin and subcutaneous tissue. The objective response rate following a single session of treatment exceeds 80%, with minimal toxicity for the patients. The efficacy of ECT in the bone and visceral metastasis is currently investigated, and Phase II studies have been completed. ECT has been used to treat skin primary tumors, except melanoma, and is under investigation for locally advanced pancreatic cancer. Early evidence suggests that treatment of tumor nodules with ECT recruits components of the immune system and eliciting a systemic immune response against cancer is a challenging clinical perspective. Considering the proven safety in several different clinical applications electroporation should be viewed as a clinical platform technology with wide perspectives for use in ECT, gene therapy and DNA vaccination.