Operating Procedures of the Electrochemotherapy for Treatment of Tumor in Dogs and Cats
October 24th, 2016
Electrochemotherapy is the local treatment of solid tumors. The main mechanism is electroporation-mediated permeabilization of the tumor cells' membrane which enables increased internalization of cytostatics like bleomycin and cisplatin. Thus, antitumor effectiveness is potentiated at the site of the application of electric pulses to the tumors.
The overall goal of this procedure is to treat cutaneous and subcutaneous tumors in dogs and cats with the use of cytostatic drugs in combination with the application of electric pulses. Electrochemotherapy is a local approach which is used for treating solid tumors of different histologies. Its mechanism is based on the cell membrane permeabilization by means of electroporation.
The main mechanism of electrochemotherapy is to enhance the effectiveness of chemotherapeutic drugs by electropermeabilization, which increases intracellular drug accumulation. Electroporation causes an increased drug uptake of two chemotherapeutics, bleomycin and cisplatin, which are hydrophilic drugs with poor membrane permeability. The presented case shows the treatment procedure for the German boxer dog with a diagnosed mast cell tumor on the lower eyelid.
Two different routes of administration can be used with the electrochemotherapy, intratumoral and intravenous. Cisplatin can be administered intratumorally, whereas bleomycin can be administered intratumorally or intravenously. The concentration of the drugs are low, without systemic side effects.
Applications of electric pulses can be carried out with any generator of electric pulses that produces square-wave electric pulses of appropriate amplitude and duration with adequate frequency. The generator used for the purposes of making this video has an integrated software and a touchscreen interface to select pre-designed electric pulses. It is equipped with a handheld electrode holder with a pulse-activating button attached to the generator by a cord.
Electric pulses are triggered by a foot switch. When injecting the drug intratumorally, the sign of good tissue retention is the tissue whitening. Pay attention to the drug leakage that can occur during the intratumoral injection.
Electric pulses should be applied as quickly as possible in order to obtain the vasoconstricting effect, which contributes to the retention of the drug solution that is injected. A good contact between electrodes and the skin is very essential, which can be assured by depilation and application of water-based gel when plate electrodes are used. Electric pulses are delivered via electrodes that can have different configurations.
Plate or needle electrodes can be used. Its choice is dependent on the tumor location, size, and its thickness. In this case, non-invasive plate stainless steel electrodes with a seven-millimeter distance between the electrodes were used.
Parameters of square-wave electric pulses are set on the touchscreen. Another characteristic of electrochemotherapy is the induction of a vascular lock, or decreased blood flow within the tumor, and consequently the retention of chemotherapeutic drugs within, which can be seen as a mild and brief ischemia. Consequently, due to the vascular disrupting effect, the possible bleeding of the treated tumor is prevented.
The first examination is recommended after one week in order to evaluate the possible local and systemic side effects. After one week, the tumor ulcerated and the area around the tumor was slightly swollen. Follow-up visit after one month serves as an evaluation of treatment response.
Treatment response is dependent on a difference in tumor volume. Therefore, tumor nodules are measured with Vernier caliper and photographed. In four weeks, no evidence of the tumor was noted.
The wound was closed, and cicatrix with alopecia was seen at the treatment site. After treatment, the dog did not show any pain, the function of the eyelid has been preserved during all the healing time, and cosmetic effects after treatment are excellent. Electrochemotherapy can be applied on solitary or multiple cutaneous or subcutaneous tumor nodules with a curative intent or as an adjuvant treatment to surgery.
Electrochemotherapy is effective as one-time treatment only, but in the case of failure or partial tumor response it can be repeated several times with improved effectiveness. In conclusion, the advantages of electrochemotherapy are its simplicity, short duration of treatment sessions, low chemotherapeutic doses, and insignificant side effects. In addition, it is performed on outpatient basis.
Therefore, the patients do not have to stay in the hospital.
Overview
Electrochemotherapy is a local treatment for solid tumors in dogs and cats, enhancing the effectiveness of cytostatic drugs through electroporation. This method increases drug uptake, particularly for bleomycin and cisplatin, leading to improved treatment outcomes.
Key Study Components
Area of Science
- Veterinary oncology
- Electrochemotherapy
- Pharmacology
Background
- Electrochemotherapy combines electric pulses with cytostatic drugs.
- It is effective for treating cutaneous and subcutaneous tumors.
- The technique relies on electroporation to enhance drug permeability.
- Low doses of drugs minimize systemic side effects.
Purpose of Study
- To demonstrate the effectiveness of electrochemotherapy in treating a mast cell tumor in a dog.
- To evaluate the procedure's outcomes and side effects.
- To explore the application methods for drug administration.
Methods Used
- Intratumoral and intravenous administration of bleomycin and cisplatin.
- Application of electric pulses using a specialized generator.
- Monitoring of tumor response and side effects post-treatment.
- Use of Vernier calipers for tumor measurement and photographic documentation.
Main Results
- Significant tumor reduction observed after treatment.
- No systemic side effects reported in the treated dog.
- Excellent cosmetic outcomes with preserved eyelid function.
- Follow-up evaluations indicated successful treatment response.
Conclusions
- Electrochemotherapy is a simple and effective treatment for solid tumors.
- It can be performed on an outpatient basis with minimal side effects.
- Repeat treatments may enhance effectiveness in cases of partial response.
Frequently Asked Questions
Executive Industry Relevance
Electrochemotherapy leverages electroporation to enhance intracellular delivery of cytostatic drugs, addressing the challenge of poor membrane permeability in solid tumor models. This approach enables localized, high-efficacy intervention with minimal systemic exposure, supporting predictive confidence in early translational oncology workflows. Its repeatability and outpatient feasibility position it as a scalable tool for preclinical and veterinary oncology pipelines.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables mechanistic interrogation of drug uptake and tumor response via controlled electroporation.
- Supports functional validation of cytostatic agents in disease-relevant solid tumor models.
- Facilitates biological de-risking by isolating local drug effects from systemic toxicity.
Screening & Assay Development
- Prepares validated tumor models for quantitative assessment of drug efficacy post-electroporation.
- Standardizes application of electric pulses and drug dosing for reproducible outcomes.
- Enables robust measurement of tumor volume changes using calipers and imaging.
Translational & Preclinical Research
- Aligns with translational biomarker strategies by enabling localized, quantifiable tumor response.
- Supports continuity from in vivo discovery to preclinical validation in veterinary and comparative oncology.
- Provides a platform for risk-adjusted advancement of local drug delivery modalities.
Pipeline & Workflow Integration
Electrochemotherapy integrates into the discovery-to-preclinical continuum by enabling hypothesis-driven evaluation of drug delivery and tumor response in solid tumor models.
- Discovery Biology: Facilitates testing of drug permeability and retention mechanisms in situ.
- Screening: Provides reproducible, quantitative tumor response data for compound evaluation.
- Analytics: Delivers measurable outputs such as tumor volume reduction and photographic documentation.
- Translational Research: Bridges local intervention studies with broader preclinical oncology programs.
- Enterprise Reuse: Offers a standardized, repeatable protocol adaptable across tumor types and species.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in drug-tumor interaction and response.
- Operational Value: Enables outpatient, short-duration procedures with minimal side effects.
- Strategic Value: Reduces late-stage biological risk through localized, low-dose interventions.
- Portfolio Impact: Supports risk-adjusted prioritization of local delivery and combination therapy candidates.
Implementation Considerations
- Requires expertise in electroporation and veterinary oncology procedures.
- Needs access to calibrated electric pulse generators and compatible electrodes.
- Demands cross-team standardization of drug dosing and pulse parameters.
- Adaptable to various tumor locations and sizes with appropriate electrode selection.
- Limited to tumors accessible for electrode placement and local drug administration.
