Electrochemotherapy: Actual Considerations and Clinical Experience in Head and Neck Cancers

Electrochemotherapy as a First Line Treatment in Recurrent Squamous Cell Carcinoma of the Oral Cavity and Oropharynx PDL-1 Negative and/or with Evident Contraindication to Immunotherapy: A Randomized Multicenter Controlled Trial

BACKGROUND

A significant proportion of patients with head and neck squamous cell carcinoma (HNSCC) have advanced-stage disease (stages III to IVB) that do not respond to therapy despite aggressive, site-specific multimodality therapy. A great number of them will develop disease recurrence, with up to 60% risk of local failure and up to 30% risk of distant failure. Therapy can be very demanding for the patient especially when important anatomical structures are involved. For these reasons, therapies that preserve organ functionality in combination with effective local tumor control, like electrochemotherapy (ECT), are of great interest. Until few months ago, systemic cetuximab + platinum-based therapy + 5-fluorouracil represented the standard treatment for HNSCC relapses with a median overall survival of 10.1 months and an objective response rate of 36%. Recently the results of KEYNOTE-048 study were published and a new combination of monoclonal antibody named pembrolizumab and chemotherapy emerged as standard first line therapy of recurrent or metastatic tumor that overexpress tissue PDL-1 (Programmed Death 1 ligand). Nevertheless, a variable percentage from 10 to 15% of patients with recurrent/metastatic disease have a tumor that does not overexpress tissue PDL-1, and therefore, according to the results of the KEYNOTE-048 study, does not benefit from replacement of cetuximab with pembrolizumab. These patients will be treated with the "gold standard": cetuximab, cisplatin/carboplatin and 5-fluorouracil.

AIM

To verify whether electrochemotherapy performed with bleomycin of HNSCC relapses of the oral cavity and oropharynx (single relapse on T) is able to lead to an increase in the objective response rate in comparison with the systemic treatment with cetuximab + platinum-based therapy + 5-fluorouracil in patients with PDL-1 negative tumors.

METHODS

The phase IIb study involves the enrolment of 96 patients who meet the inclusion criteria (48 in the control arm and 48 in the treatment arm). The control arm involves the treatment of HNSCC with systemic treatment (cetuximab + platinum-based therapy + 5-fluorouracil). The treatment arm involves the ECT with bleomycin. The primary objective is to verify the objective response rate of patients in the control arm compared to the treatment arm.

Electrochemotherapy in Mucosal Cancer of the Head and Neck: A Systematic Review

Electrochemotherapy (ECT) is a local ablative treatment that is based on the reversible electroporation and intracellular accumulation of hydrophilic drug molecules, which greatly increases their cytotoxicity. In mucosal head and neck cancer (HNC), experience with ECT is limited due to the poor accessibility of tumors. In order to review the experience with ECT in mucosal HNC, we undertook a systematic review of the literature. In 22 articles, published between 1998 and 2020, 16 studies with 164 patients were described. Curative and palliative intent treatment were given to 36 (22%) and 128 patients (78%), respectively. The majority of tumors were squamous cell carcinomas (79.3%) and located in the oral cavity (62.8%). In the curative intent group, complete response after one ECT treatment was achieved in 80.5% of the patients, and in the palliative intent group, the objective (complete and partial) response rate was 73.1% (31.2% and 41.9%). No serious adverse events were reported during or soon after ECT and late effects were rare (19 events in 17 patients). The quality-of-life assessments did not show a significant deterioration at 12 months post-ECT. Provided these preliminary data are confirmed in randomized controlled trials, ECT may be an interesting treatment option in selected patients with HNC not amenable to standard local treatment.

Long term effectiveness of electrochemotherapy for the treatment of lower lip squamous cell carcinoma

PURPOSE

Electrochemotherapy (ECT) is a therapeutic approach based on the local application of electrical pulses that permeabilize cell membranes to enhance the uptake of low-permeant chemotherapeutic agents, thus increasing their cytotoxic effects.

MATERIALS AND METHODS

Twenty-one patients with SCC of the lower lip were treated according to the European Standard Operating Procedures of Electrochemotherapy. Bleomycin (15,000 IU/m² body surface area) was administered intravenously over a 1-min period. Eight electrical pulses (amplitude, 1000 V/cm; duration, 100 μs) were generated and delivered at a repetition frequency of 5 kHz. Changes in tumor volume were used to assess treatment response.

RESULTS

Objective response (OR), complete response (CR), and partial response (PR) rates of 100%, 71.4%, and 28.6% respectively were demonstrated following a single session of ECT. ECT was well tolerated, and no adverse events occurred.

CONCLUSIONS

Intravenous bleomycin-based ECT is a safe and effective therapy for SCC of the lower lip. ECT improves the quality-of-life of patients by preserving the function and the aesthetic appearance of the affected area. ECT provides a therapeutic option for elderly and frail patients who, due to their state of health, are not suitable for, or refuse surgical interventions.

Electrochemotherapy for the Treatment of Recurrent Head and Neck Cancers: Preliminary Results

Aims and background

Electrochemotherapy is a tumor ablation modality providing delivery into the cell interior of impermeant or poorly permeant chemotherapeutic drugs such as cisplatin and bleomycin. A locally applied electrical field enhances the membrane permeability allowing intracellular accumulation of the chemotherapeutic agent. The aim of the study was to evaluate the effectiveness of ECT for the treatment of a group of patients affected by recurrent of extended primary head and neck cancer and not suitable for standard therapeutic options.

Methods and study design

From April 2009 to January 2011, we treated with electrochemotherapy a total of 15 patients with head and neck cancers, 13 with squamous cell carcinoma, 1 with basaloid carcinoma and 1 with Merkel cell carcinoma. Electrical pulses were delivered to 33 lesions (3 primaries, 30 recurrences) after an intravenous bolus injection of a dose of 15,000 IU/m2 of bleomycin. In 3 cases, the lesion treated was a pathologic lymph node.

Results

Of the 31 lesions assessable for the study, 19 (61.5%) showed a complete response, 10 (32.5%) a partial response, 1 (3%) stable disease and 1 (3%) progression of the disease. The objective response 2 months after the procedure was 94%. All the lesions that underwent complete regression were less than 3 cm in their maximum diameter. The 2 assessable cases of pathologic lymph nodes showed a partial or no response. After a follow-up of 2 to 20 months, 29% of the patients were alive and free of disease, 50% were alive with disease, 14% died for disease and 7% died for other causes.

Conclusions

Our study confirms the effectiveness of electrochemotherapy in the treatment or local control of recurrent or extended primary head and neck cancer in patients not suitable for standard therapeutic options.

Electrochemotherapy of mucosal head and neck tumors: a systematic review

BACKGROUND

Electrochemotherapy, the combination of electroporation and chemotherapy, is mainly used in the palliative setting for treatment of cutaneous and subcutaneous metastases; however, new applications are continuously being explored. Patients with head and neck cancer are primarily treated with surgery and/or radio-chemotherapy. In the setting of local recurrence with no further curative treatment options available, electrochemotherapy could be of value. We therefore performed a systematic search of the present literature.

MATERIALS AND METHODS

Eligible studies presented data from patients with head and neck cancer treated across the mucosal surface with electrochemotherapy. The search resulted in 11 studies with a total of 72 patients.

RESULTS

Overall complete response was reported as good, especially in primary small tumors. Side effects were minor in primary tumors whereas large, recurrent tumors displayed more frequent side effects and some serious adverse events. Design and structure of the studies differed considerably, making general comparisons difficult.

CONCLUSION

Few studies concerning electrochemotherapy on mucosal head and neck tumors are available and they are not easily comparable. Overall response to treatment is good; nonetheless, further systematic studies are warranted.

Metastatic sebaceous cell carcinoma, review of the literature and use of electrochemotherapy as possible new treatment modality

Background

Metastatic extraorbital sebaceous carcinoma is a rare event that could involve the head and neck. The treatment of choice for the initial stage of the disease is surgery and/or radiotherapy. The treatment of recurrent or advanced disease is still controversial.

Material and methods

Extensive literature search was done, and the treatment options are discussed.

Results

Results. The literature search found several treatment modalities in use for the treatment of metastatic extraorbital sebaceous carcinoma. Electrochemotherapy was not included in the reported treatments. We used this technique for a man of 85 years old with a recurrent and locally metastatic extraorbital sebaceous carcinoma of the scalp. During the period of 8 months, two sessions of electrochemotherapy were employed, which resulted in an objective response of the tumour and good quality of life.

Conclusions

Electrochemotherapy has shown to be a interesting tools for treatment of metastatic extraorbital sebaceous carcinoma when other radical options are not available or convenient.

Outcomes of Bleomycin-based electrochemotherapy in patients with repeated loco-regional recurrences of vulvar cancer

Objective To evaluate the safety, local tumor efficacy and relief of symptoms of electrochemotherapy (ECT) treatment in patients affected by recurrence of vulvar cancer (VC), unsuitable for standard treatments. Methods Ten patients were recruited with histological diagnosis of recurrence of VC. Intravenous bleomycin was injected, after an accurate mapping of all lesions and ECT was performed. Response to therapy was evaluated and quality of life (QoL) was evaluated via questionnaires. Results Diagnosis stage of primary tumors, according to the FIGO system, was: four patients respectively at stage IB (40%), and at stage II (40%), one patient at stage IIIA (10%), one patient with Paget cancer (10%). Mean age was 76 years (SD ± 7) at time of enrollment. Eight patients (80%) were previously submitted to surgery and/or radio-chemotherapy. Mean treatment time was 20 (range 10-20) min. After a median follow-up of 12 (3-22) months, six patients (60%) were alive. Conclusions Objective responses (ORs) with local control of the tumor were obtained in 80%. After a mean follow-up of 12 (3-22) months six patients (60%) were alive. The favorable outcome of this study, indicates that ECT is a reliable treatment option that may improve their functioning, thus enhancing the care provided in the palliative setting.

Electrochemotherapy to Metastatic Spinal Melanoma: A Novel Treatment of Spinal Metastasis?

STUDY DESIGN

Preliminary report of new antitumor treatment.

OBJECTIVE

To evaluate the effectiveness of electrochemotherapy as a novel treatment of spinal metastasis.

SUMMARY OF BACKGROUND DATA

Electrochemotherapy is a new antitumor treatment that combines systemic bleomycin with electric pulses delivered locally at the tumor site. These electric pulses permeabilize cell membranes in the tissue, allow bleomycin delivery diffusion inside the cells, and increase bleomycin cytotoxicity. Previous clinical studies have demonstrated the effectiveness of electrochemotherapy in the treatment of several primary and metastatic solid tumors.

METHODS

Treatment planning for electrode positioning and electrical pulse parameters was prepared for 4 needle electrodes. Mini-open surgery with a left L5 laminectomy was performed to introduce the eletrodes. The patient was treated according to the established Electrochemotherapy Protocol with Bleomycin. Clinical efficacy of electrochemotherapy was evaluated according to a visual analog scale of pain, Oswestry Disability Index 2.0, the Karnofsky Performance Scale, and Response Evaluation Criteria in Solid Tumors.

RESULTS

The assessed follow-up period was 48 months after the electrochemotherapy procedure. Neither serious electrochemotherapy-related adverse events, nor bleomycin toxicity were reported. Overall improvement in pain according to Oswestry Disability Index 2.0 and Karnofsky Performance Scale outcomes was better.

CONCLUSION

Our case represents, to our knowledge, the first one to test the potential role of electrochemotherapy as treatment of spinal metastasis. Electrochemotherapy allowed a successful treatment of metastatic spinal melanoma. However, we believe that there is a strong scientific rationale to support the potential utility of electrochemotherapy as a novel treatment of spinal metastasis, regardless of the histological types.

LEVEL OF EVIDENCE

5.

Electrochemotherapy in combination with chemoradiotherapy in the treatment of oral carcinomas in advanced stages of disease: efficacy, safety, and clinical outcomes in a small number of selected cases

Introduction

Electrochemotherapy (ECT) is a new therapeutic method that is used in oncology as palliative treatment in patients with recurrent head and neck tumors and who are not candidates for standard therapeutic options. The aim of our study was to evaluate the cytoreductive effect of ECT in patients subjected to chemoradiotherapy for squamous cell carcinoma of the oral cavity. The primary endpoint of the study was to verify tumor debulking after ECT treatment as neoadjuvant, before conventional chemoradiotherapy. The secondary endpoint was to assess the safety and tolerability of ECT treatment.

Materials and methods

This experimental study was conducted at the Division of Otolaryngology, University of Catanzaro, Italy. From February 2013 to February 2014, four patients were enrolled, two males and two females, with a mean age of 56 years (range: 47–65 years), and with squamous cell carcinoma of the oral cavity in advanced stages of disease (T3–T4). All patients, with their informed consent, received ECT treatment in accordance with the Standard Operating Procedures defined in the European Standard Operating Procedures on Electrochemotherapy (ESOPE) study, followed by conventional chemoradiotherapy. Their response to ECT treatment was assessed after 30 days. For each patient, the following parameters were evaluated with the appropriate forms: local tumor control, control of pain (analgesia postsurgery scale [APS]), and quality of life (Short Form [36] Health Survey [SF-36]; v1).

Results

Three of four patients (75%) showed a partial response, whereas in one patient (25%), the disease remained stable. The treatment was well-tolerated by all patients, according to the APS and SF-36 results.

Conclusion

Although the study was conducted on a small number of cases, data from this study show that ECT represents a safe and effective treatment in terms of tumor cytoreduction and locoregional control of the disease. It also allows good control of postoperative pain and short hospitalization.

Electrochemotherapy: from the drawing board into medical practice

Electrochemotherapy is a local treatment of cancer employing electric pulses to improve transmembrane transfer of cytotoxic drugs. In this paper we discuss electrochemotherapy from the perspective of biomedical engineering and review the steps needed to move such a treatment from initial prototypes into clinical practice. In the paper also basic theory of electrochemotherapy and preclinical studies in vitro and in vivo are briefly reviewed. Following this we present a short review of recent clinical publications and discuss implementation of electrochemotherapy into standard of care for treatment of skin tumors, and use of electrochemotherapy for other targets such as head and neck cancer, deep-seated tumors in the liver and intestinal tract, and brain metastases. Electrodes used in these specific cases are presented with their typical voltage amplitudes used in electrochemotherapy. Finally, key points on what should be investigated in the future are presented and discussed.

Electrochemotherapy as a new therapeutic strategy in advanced Merkel cell carcinoma of head and neck region

Background

Merkel Cell Carcinoma (MCC) is a rare and aggressive tumour, arising from a cutaneous mechanoceptor cell located in the basal layer of epidermis, with poor prognosis. The treatment of choice for the initial stage of the disease is surgery and/or radiotherapy. The treatment of recurrent or advanced disease is still controversial.

Case report

We report a case of 84 years old woman with a recurrent MCC of the chin treated with electrochemotherapy (ECT). During the period of 20 months, four sessions of ECT were employed, which resulted in an objective response of the tumour and good quality of residual life.

Conclusions

Our case shows the effectiveness of ECT in the treatment of locally advanced MCC of the head and neck region in a patient not suitable for standard therapeutic options.

Antitumor effectiveness of electrochemotherapy: a systematic review and meta-analysis

BACKGROUND

This systematic review has two purposes: to consolidate the current knowledge about clinical effectiveness of electrochemotherapy, a highly effective local therapy for cutaneous and subcutaneous tumors; and to investigate the differences in effectiveness of electrochemotherapy with respect to tumor type, chemotherapeutic drug, and route of drug administration.

METHODS

All necessary steps for a systematic review were applied: formulation of research question, systematic search of literature, study selection and data extraction using independent screening process, assessment of risk of bias, and statistical data analysis using two-sided common statistical methods and meta-analysis. Studies were eligible for the review if they provided data about effectiveness of single-session electrochemotherapy of cutaneous or subcutaneous tumors in various treatment conditions.

RESULTS

In total, 44 studies involving 1894 tumors were included in the review. Data analysis confirmed that electrochemotherapy had significantly (p < .001) higher effectiveness (by more than 50%) than bleomycin or cisplatin alone. The effectiveness was significantly higher for intratumoral than for intravenous administration of bleomycin (p < .001 for CR%, p = .028 for OR%). Bleomycin and cisplatin administered intratumorally resulted in equal effectiveness of electrochemotherapy. Electrochemotherapy was more effective in sarcoma than in melanoma or carcinoma tumors.

CONCLUSIONS

The results of this review shed new light on effectiveness of electrochemotherapy and can be used for prediction of tumor response to electrochemotherapy with respect to various treatment conditions and should be taken into account for further refinement of electrochemotherapy protocols.

Distant metastases from head and neck squamous cell carcinoma. Part III. Treatment

Distant metastases from head and neck squamous cell carcinoma (HNSCC), though rare at initial presentation, remain an important manifestation of cancer recurrence and mortality. Although generally considered incurable with a dismal prognosis despite palliative therapy, highly selected patients with distant metastases may have a long term survival benefit from aggressive surgery or radiotherapy. Advances in systemic treatments also may improve patient survival. This article reviews the current state of management of HNSCC patients with distant metastases.

Irreversible electroporation on the small intestine

BACKGROUND

Non-thermal irreversible electroporation (NTIRE) has recently been conceived as a new minimally invasive ablation method, using microsecond electric fields to produce nanoscale defects in the cell membrane bilayer and induce cell death while keeping all other molecules, including the extracellular matrix, intact. Here, we present the first in vivo study that examines the effects of NTIRE on the small intestine, an organ whose collateral damage is of particular concern in the anticipated use of NTIRE for treatment of abdominal cancers.

METHODS

A typical NTIRE electrical protocol was applied directly to the rat small intestine and histological analysis was used to examine the effect of NTIRE over time.

RESULTS

The application of NTIRE led to complete cell ablation in the targeted tissue, but the animal did not show any physiological effects of the procedure and the intestine showed signs of recovery, developing an epithelial layer 3 days post treatment and regenerating its distinct layers within a week.

CONCLUSION

Our results indicate that this novel procedure can be used for abdominal cancer treatment while minimising collateral damage to adjacent tissues because of the unique ability of the NTIRE ablation method to target the cell membrane.