Congenital dermal hemangioendothelioma in two foals.

This study details the two cases that were encountered in one year of congenital dermal hemangioendothelioma in foals. Hemangioendothelioma, relatively unreported in horses, is a vascular tumor of the skin.

Background

• The research paper starts by establishing the rarity of reports regarding congenital dermal hemangioendothelioma, a type of vascular tumor, in horses.
• Other types of tumors previously studied in equine subjects, including cutaneous papilloma, subcutaneous melanoma, and subcutaneous lymphangioma, are highlighted.

Case Study 1

• A seven-week-old male standardbred foal exhibiting an enlarged right front fetlock-pastern area since birth is presented in the first case study.
• The absence of lameness until the skin over the enlargement turned ulcerated, infected, and frequently bled, led to the investigation of the ailment.
• A skin biopsy reveals the mass to be histologically compatible with hemangioendothelioma, confirming the rare occurrence of this tumor in foals.
• Due to persistent bleeding and ulceration, as well as a poor prognosis for complete removal, the decision was made to euthanize the foal for humane reasons.

Post-Mortem Examination

• The autopsy revealed extensive edema of the entire right foreleg and the presence of an irregular, elevated soft tissue mass primarily involving the caudomedial aspect of the right front fetlock and pastern.
• The ulcerated surface displayed multifocal ulcers and diffuse papilliferous projections among other signs.
• Upon deeper examination, the underlying dermal tissue was found to be thickened, soft, white-tan in appearance, and presented scattered red foci, characteristic of inflammation.