Various treatments have been tried on equine sarcoids, with varying results. In many cases, the sarcoids are of cosmetic concern, while in other cases they interfere with tack, equipment and performance. Some lesions are inoperable due to location.
A new technique might hold promise for effective resolution [Frandsen, S.S.K.; Gehl, J.; Tramm, T.; and Thoefner, M.S. Calcium Electroporation of Equine Sarcoids. Animals March 2020, 10, 517; doi:10.3390/ani10030517].
The process of calcium electroporation relies on Injection of calcium into a sarcoid tumor followed by high-voltage electric pulses to open cell membranes transiently for uptake of calcium, which then kills the cells. Cancer cells and tissues are more affected by this process than normal cells and tissue.
The Danish study treated eight horses—with a total of 32 sarcoids—with this technique under general anesthesia, then evaluated size of the tumors over 12–38 weeks. (One horse with five sarcoids was withdrawn from the study for unrelated reasons.) A second treatment was administered if the sarcoid wasn’t eliminated by the first treatment. Many of the fibroblastic or verrucous sarcoids were located on the ventral abdomen, and other lesions were present on the limbs, neck and head regions.
The results of treatment yielded a 44% total response rate:
- 22% (6 of 27) of sarcoids were eliminated completely—these were on the heads, necks and ventral abdomens of four horses
- 22% (6 of 27) of sarcoids decreased by more than 30%—these were in all locations, including the limbs
- Progressive increases in size (up to 20%) were observed in 30% (8 of 27) on five horses
Efficacy of the electroporation treatment was found to be unrelated to type of lesion, size, location or individual horse. Not all sarcoids on each individual horse responded to treatment—this indicated that the response is based on the sarcoid itself rather than host-related factors. In addition, no systemic immune effects were associated with treatment.
In summary, calcium electroporation is considered safe for treatment of localized equine sarcoids, including those that are inoperable.