Long‐term outcome with neoadjuvant electrochemotherapy and sliding canthoplasty in a cat with locally advanced squamous cell carcinoma of the lower and third eyelid

A 10-year-old, female, spayed cat was referred with a lower eyelid mass lesion of the right eye. Fine-needle aspiration cytology and histopathology revealed a locally advanced squamous cell carcinoma. The cat was treated with three sessions of neoadjuvant electrochemotherapy, which was associated with a good response. After electrochemotherapy treatment, a sliding canthoplasty was performed to reconstruct the eyelid margin. Histology of excised tissue during surgery, post-electrochemotherapy, demonstrated a lack of neoplastic cells. The patient was still in complete remission 22 months after diagnosis. All treatments were well tolerated, with mild-to-moderate and self-limiting local toxicities, allowing normal eyelid function and preservation of sight. This multi-modal approach resulted in a long-term local control. This case report highlights the potential benefit of electrochemotherapy in the neoadjuvant setting, enabling surgical removal and long-term local tumour control.