Electrochemotherapy with bleomycin for bilateral ocular squamous cell carcinoma in a horse.

Objective: To describe the procedure and outcome of electrochemotherapy (ECT) with bleomycin as a first-line treatment for bilateral ocular surface squamous neoplasia (OSSN) in the eye of a horse.
Animal Studied: A client-owned 5-year-old Haflinger gelding with limbal-conjunctival squamous cell carcinoma.
Procedures: During general and local anesthesia, injection of bleomycin in the ocular tumor was followed by electroporation, applied with a 15 mm needle electrode, needles held parallel to the ocular surface.
Results: Treatment with ECT resulted in therapeutic electric pulses and complete tumor response with no recurrence during follow-up. Tumor toxicity as a result of treatment was mild, with no adverse effect to normal tissue.
Conclusions: In this case of bilateral ocular tumors, staged ECT with bleomycin was shown to be a safe and effective treatment with complete tumor remission and no recurrence during the observation period. The result suggests ECT as a possible treatment in ocular tumors, with further research recommended.
(© 2024 American College of Veterinary Ophthalmologists.)