Electrochemotherapy for feline lingual squamous cell carcinoma: a case report of functional preservation as a palliative approach.

A 14-year-old spayed female Persian cat with lingual feline oral squamous cell carcinoma (FOSCC) was treated with bleomycin-based electrochemotherapy (ECT), resulting in sustained preservation of oral function and quality of life despite advanced disease. At presentation, the cat exhibited severe weight loss, oral pain, and reduced voluntary food intake. ECT was performed using intravenous bleomycin (20 mg/m2) followed by electric pulse delivery via an eight-needle electrode array. Following treatment, marked tumor regression was observed, accompanied by substantial reduction in oral pain, restoration of voluntary feeding, and body weight gain from 1.7 kg to 2.6 kg during the treatment period. Voluntary eating and drinking were preserved throughout the clinical course until the terminal stage. Repeated examinations under general anesthesia revealed no gross abnormalities in the larynx or tonsils. The cat died due to renal failure unrelated to tumor progression. Postmortem histopathology revealed extensive SCC infiltration involving the tongue base, tonsils, and epiglottis despite the absence of clinical abnormalities during life. This case demonstrates that ECT can provide meaningful palliation, including preservation of oral function and quality of life, in cats with biologically advanced lingual FOSCC. In addition, the marked discrepancy between clinical findings and histopathologic tumor extent suggests the possibility of clinically inapparent regional spread, which may have important implications for staging and treatment planning. These findings also suggest that ECT may preserve superficial functional structures while allowing progression of submucosal tumor components.