Electrochemotherapy (ECT) is a cancer treatment that uses electrical pulses to create temporary holes in cancer cell membranes, allowing drugs to enter the cells more effectively. This process, called electroporation, results in targeted cell death within the tumor while sparing normal tissues (reversible electroporation).
The procedure involves administering Calcium Chloride or chemotherapy drugs (Bleomycin/ Cisplatin) given intravenously or directly into the tumor. Shortly after drug injection, electrodes are used to deliver short electrical pulses to the area. ECT usually requires two treatments, spaced two weeks apart.
Reversible electroporation, means that tissues are maintained post ECT when voltages charges used are between 200V up to 600V and irreversible electroporation which induces cell death by electrical charge when voltage discharges of 600V to 1500V are used.
Side effects are minimal, with mild skin irritation being the most common for reversible electroporation. Irreversible elctroporation leads to more significant cell death with an open wound.
ECT has moved from a palliative care treatment to a first line cancer treatment. It is generally safe for most patients, and its success rate is high, leading to significant clinical improvements and enhanced quality of life for treated patients.
What tumours can be treated?
Electrochemotherapy (ECT) is a able to treat any cancer as long as the electrodes can be placed against the tumour. Most commonly the skin and subcutaneous, but also the ear, nose and throat regions. Internal organ ECT is possible, and can be used for bone cancer metastases.
The most encouraging is that it can be used in limb sparing surgeries to treat sarcomas in legs that would normally require leg amputation.
Treatment of dirty margins when a second operation is required, or where no chance of getting a clean surgical margin is possible.
What are the side effects?
Reversible electroporation leaves a mild reddening of tissue and there may be a mild ulceration of the skin. Irreversible electroporation causes more tissue damage that may take two to three weeks to heal, occasional burning may be seen as a pink scar.
Local irritation post ECT treatment may lead to self trauma, thus a protective collar and anti-inflammatory pain relief is often used to lessen these effects.
The electrical current causes muscle contractions, it is for this reasons animals must be under full general anaesthetic. The electrical charge does not interreact with the heart.
Use of isotonic calcium chloride means there is minimal effects from use of this drug. Even if the chemotherapy drugs are used - the dose is so small they have very minimal effect on the animals.
Standard care of the patient for general anaesthesia must be considered with the use of pre anaesthetic blood testing to ensure the patient is safe to undergo general anaesthesia.
What is the effectiveness of ECT ?
In general, the rate of complete tumor regression after ECT treatment is high, although it can vary depending on the type and size of the tumor. ECT often leads to long-lasting responses, but in some cases, recurrence may occur. Even when a partial response is observed, ECT can still bring about clinical improvements, notably in terms of reduced pain, less bleeding, and decreased reliance on medical care.
When can ECT not be used ?
There is no known reason to not to undergo ECT therapy, however each individual patient must be evaluated for suitability of the procedure.
Immune modulating effect of ECT therapy
In current research there is a volume evidence mounting that shows that ECT is activating the immune system to act against the cancer. The innate immune system is activated by the DAMPS pathways. The most important is to have a viable and responsive immune system to be able to react to this stimulating effect of ECT.
The exciting evidence is showing that there may be a distant response to tumours not treated whilst receiving treatment in local areas in patients. Thus , ECT is inducing a systemic effect against the cancer. See the Case Report.