Pet Electrochemotherapy

What is Electrochemotherapy?

Electrochemotherapy is a type of treatment delivered directly to the tumor or site of tumor removal that enhances the delivery of traditional chemotherapy to the cancer cells. The electrochemotherapy process involves an injection of chemotherapy either IV or into the tumor region, followed by applying short bursts of high voltage electric pulses. These pulses open cellular membranes, thereby increasing the uptake of chemotherapy up to a thousandfold into the cell, where it can act to kill the tumor cells in a more efficient and localized manner.

What types of tumors are typically treated with Electrochemotherapy?

Electrochemotherapy is typically reserved for small tumors (<3cm) located in regions not amenable to surgical excisions, such as the face, oral cavity, and perineal region. Electrochemotherapy is also often an option for treatment of a site where a tumor had been removed via surgery with incomplete margins in an attempt to reduce the risk of local recurrence, much in the same way radiation therapy would be employed. While electrochemotherapy is not a head-to-head replacement for radiation therapy, it can be used as an alternative if radiation therapy is not an option for a client or pet.

Common Types:

• Soft tissue sarcoma
• Squamous cell carcinoma
• Mast cell tumor
• Melanoma/melanocytoma
• Dermal hemangiosarcoma
• Perineal tumors

Electrochemotherapy Protocol:

Because electrochemotherapy involves the administration of high voltage electric pulses that can be uncomfortable to the patient, animals are briefly anesthetized for the procedure. In most instances, patients are anesthetized for less than 10 minutes, which allows for the administration of chemotherapy either IV or into the tumor site and delivery of the electric pulses. Patients are often sent home with 1-2 weeks of anti-inflammatory pain medications to help with soreness related to the procedure. Electrochemotherapy is typically administered in 1 to 2 sessions, separated by 2-4 weeks.

What are the side effects of electrochemotherapy?

In general, electrochemotherapy is very well tolerated, but side effects such as swelling, redness, and in some cases, skin/tumor ulceration can occur. If an ulceration or other damage to the tissue occurs, healing usually takes place quickly and uneventfully without surgical or other invasive intervention.

What data are available with regards to the efficacy of Electrochemotherapy?

Electrochemotherapy is a relatively new treatment modality, and therefore large clinical trials have yet to be performed in veterinary patients. Many small reports have documented positive responses both for treating gross tumors directly as well as preventing tumor recurrence after removal. The most studied tumor types include mast cell tumors, squamous cell carcinoma, and soft tissue sarcoma.

How do I find out more information?

In many cases, electrochemotherapy is administered as part of a comprehensive, multimodal treatment plan, including surgery or standard chemotherapy. Please contact VCSS surgery or medical oncology services to determine whether your pet is a good candidate for this treatment and whether the addition of electrochemotherapy may provide benefits for your cat or dog.