MODELING THE EFFECTS OF IONIZING RADIATION IN VETERINARY MEDICINE: CLINICAL APPLICATION OF RADIOMIMETICS IN CANINE SQUAMOUS CELL CARCINOMA

Abstract

Radiomimetics are a class of antitumor agents that mimic the effects of ionizing radiation by inducing DNA strand breaks in cancer cells. They provide therapeutic efficacy comparable to radiotherapy but without the need for expensive equipment, which makes them highly promising for veterinary oncology, especially in regions with limited access to radiation therapy. One of the most effective radiomimetic agents is bleomycin, which is widely used in electrochemotherapy (ECT) protocols. This article presents a clinical case of well-differentiated squamous cell carcinoma (G1) in a 6-year-old, 30-kg working dog. The tumor was localized in the interscapular region, characterized by firm consistency, areas of necrosis, and serous-purulent exudation. Histological examination confirmed the diagnosis of squamous cell carcinoma with squamous differentiation of neoplastic cells. The patient underwent surgical excision of the tumor followed by ECT with bleomycin at a dose of 15,000 IU/m² administered intravenously in combination with local electroporation. After the first session, a significant reduction in pain, decreased exudation, and partial reduction of the tumor mass (25–30%) were observed. Following the second session, the disease process stabilized, appetite returned, and hematological parameters improved, indicating reduced systemic intoxication. In conclusion, the combination of surgical intervention and electrochemotherapy with bleomycin demonstrated high efficacy in the treatment of squamous cell carcinoma in dogs. The use of radiomimetics ensures strong local effectiveness, good tolerance by patients, and economic feasibility, highlighting the potential of this therapeutic approach for practical veterinary oncology.