Introduction

Thermal ablation by using electromagnetic thermotherapy system has been a promising cancer treatment modality in recent years. This system applies a high-frequency alternating electromagnetic field to heat up apace the alloy needles which are inserted into and beneath the target tumor to cause denaturation of surrounding tissues or vessels and eventually coagulative necrosis.

Objectives

Use the newly developed system called electromagnetic thermoablation (EMTA) to treat oral cancers of dogs and to investigate clinical outcome after EMTA.

Methods

Seven client-owned dogs with oral tumors were treated with EMTA. These tumors included 3 malignant melanomas at buccal mucosa, tongue, and hart palate, respectively; 2 amelanotic melanomas at tongues; and 2 squamous cell carcinomas at buccal mucosa and tongue, respectively. The heat of needle reached to 90–100°C in 30 seconds and then was maintained at this temperature for 270 seconds to complete a 300-second procedure. The effective area of each needle after heating was 5 mm in radius from center of needle.

Results

Six tumors showed no recurrence after EMTA. The mean relapse-free interval was 327.5 days (median 305.5 days) to the date of this abstract submitted. Only one dog with large-sized malignant melanoma at root of tongue showed recurrence at 25th day after EMTA. Side effects were self-limited and included regional pain, salivation or discharge. These dogs were well tolerated and showed good appetite after EMTA.

Conclusions

This EMTA might be used as an option of the local disease control in oral tumors of dogs, similar with the wide-margin surgery.