December 2006

Is That Melanoma Deadly?

If the horse is gray, probably not. But if he’s any other color, you may want to take note.

Melanomas in gray horses are most frequently found on the undersurface of the tail (about 95%). The next most likely location is around the anus and vulva of mares. They can also be found on the lips, eyelids, penis and sheath.

Melanomas are not limited to gray horses. Melanomas in other horses are found on the body or legs. Metastasis (spread) apparently occurs via the blood stream, carrying the tumor cells virtually anywhere. Metastases have been found in the skeletal muscles, gutteral pouches, salivary glands and anywhere in the chest or abdomen. There was even a recent report of spread to the brain. …