Performance characteristics of a conformal ultra-wideband multilayer applicator (CUMLA) for hyperthermia in veterinary patients: a pilot evaluation of its use in the adjuvant treatment of non-resectable tumours.

The research article presents an evaluation of a new hyperthermia applicator that works at 434 MHz for aiding in the treatment of advanced superficial tumors in cats, dogs, and horses.

Study Overview

This study had two main parts:

• The first part involved electromagnetic simulations of the novel “Conformal Ultra-Wideband Multilayer Applicator” (CUMLA) as well as a flat microwave antenna of similar dimensions to compare their electrical field characteristics and radiated power.
• The second part of this study was the practical application and evaluation of this new antenna on six animals (cats, dogs, and horses) with advanced solid tumors undergoing chemotherapy.

Simulation Results

The results of the electromagnetic simulations showcased several advantages that the CUMLA has over a conventional flat microwave antenna:

• Reduced skin surface and backfield irradiation: The novel antenna targeted only the tumor area and therefore was more safe, causing less damage to healthy tissue.
• Improved directional irradiation: There was better control and delivery of heat to the tumor, which again leads to less damage to surrounding tissue.
• Increase in radiated power and penetration depth: The CUMLA transmitted more power and was able to heat tissue deeper beneath the skin.

Clinical Application and Evaluation

The antenna was clinically applied to six animals with locally advanced solid tumors. The researchers found that:

• Therapeutic temperatures were achieved at depths greater than or equal to 4 cm: The antenna effectively heated the tumors at this substantial depth, indicating a success for the CUMLA.
• Objective responses in animals: There were notable therapeutic responses in all of the tested animals.
• Some tissue toxicity occurred in one case, which affected the ability to continue therapy: Despite the generally positive results, there was evidence of some adverse effects, which demonstrates potential scope for further study to mitigate such issues.

In conclusion, the CUMLA demonstrated a range of benefits including compactness, efficient focus and deep penetration, suggesting promise for improved hyperthermia treatment for solid tumours in veterinary patients.