Multimodal management of canine cutaneous mast cell tumor grade II: reconstructive surgery associated with electrochemotherapy

Canine cutaneous mast cell tumors represent a significant clinical challenge due to the wide variability in biological behavior and the risk of recurrence or metastasis, requiring individualized therapeutic strategies. Clinical management demands a multimodal diagnostic approach and, frequently, therapies complementary to surgery. This report describes the case of an eight-year-old mixed-breed female dog with controlled hypoadrenocorticism, which presented with cutaneous nodules on the right pelvic limb. Fine-needle aspiration cytology suggested mast cell tumor, which was confirmed by histopathology and immunohistochemistry. Staging with imaging studies did not identify distant metastases, and popliteal lymphadenectomy revealed no neoplastic infiltration. Treatment consisted of wide surgical excision with 3 cm margins, followed by reconstruction with an axial rotational flap and adjuvant electrochemotherapy with bleomycin. The postoperative course was uneventful, except for local ulceration undergoing epithelialization, later confirmed as chronic inflammatory lesion without tumor recurrence. Histopathology classified the neoplasm as grade II (Patnaik) and low grade (Kiupel), with perimembranous c-KIT expression pattern (pattern I) and Ki-67 proliferative index < 23%, indicators associated with a guarded-to-favorable prognosis despite the compromised deep margin. This case demonstrates the applicability of a multimodal approach combining reconstructive surgery and electrochemotherapy as an effective strategy for local control in mast cell tumors located in challenging anatomical sites. The importance of periodic clinical follow-up is emphasized to monitor for possible recurrences or new tumors. This report contributes to veterinary oncology practice by illustrating integrated management alternatives with both clinical and scientific relevance.