Equine basal cell tumors: 6 cases (1985-1999).

The research article discusses a rare benign tumor in horses known as a basal cell tumor. Over a period of 15 years, six cases were identified and investigated. An effective treatment strategy was surgical removal, leading to no recurrence in the majority of cases.

Basal Cell Tumors in Horses

• This research spans 15 years, during which the researchers observed six cases of horses diagnosed with basal cell tumors.
• These tumors are benign, meaning they do not spread to other parts of the body and predominantly do not have any harmful effects on the horse’s overall health.
• Despite being benign, these tumors were described as well-circumscribed (having a definite boundary), freely movable and firm. They appeared in a variety of forms such as raised papules, nodules, or masses, and ranged from 0.6 to 5 cm in diameter.

Appearance and Diagnosis

• Based on the physical appearance, five of the six tumors were described as ulcerated. This means that the skin surface of these tumors was broken, resulting in a wound or an open sore.
• Due to their visual appearance, the tumors were initially misdiagnosed: five as sarcoids and one as a melanoma, both of which are common types of skin tumors in horses with different characteristics compared to basal cell tumors.

Age Range and Symptoms Duration

• The age range of the horses affected by these tumors was quite wide, between 6 and 26 years, indicating that this condition can affect horses at any stage of adulthood.
• Before the tumors were surgically removed, they were identified clinically anywhere from one week to three years in advance. This suggests the tumors grow quite slowly and don’t immediately affect the animal’s quality of life.

Treatment and Prognosis

• Four of the horses had their basal cell tumors completely surgically removed. For these horses, the information was available and it was recorded that this treatment method was curative – there was no recurrence of the tumor from 4 months to 2 years after the surgery.