RESUMEN
Mast cell tumors (MCTs) are the most common malignant cutaneous tumors in dogs, and they present extremely variable biological behavior. The interaction between RANK, RANK-L, and immune checkpoints is frequently detected in the tumor microenvironment, and, together, they participate in every stage of cancer development. Thus, the aim of this study was to characterize the molecular profiles of PD-L1, CTLA-4, RANK/RANK-L signaling pathway, and IFN-γ in primary tumors and lymph node metastases. Formalin-fixed, paraffin-embedded slides of MCTs and metastatic lymph nodes of ten dogs were submitted to immunohistochemical investigations. The results demonstrated that the tumor microenvironment of the high-grade mast cell tumors showed moderate or intense immunolabeling of all proteins, and the lymph node metastases also showed moderate or intense immunolabeling of checkpoint proteins. In addition, MCTs larger than 3 cm were associated with intensified PD-L1 (p = 0.03) in metastatic lymph nodes and RANK-L (p = 0.049) immunoreactivity in the tumor. Furthermore, dogs with a survival time of less than 6 months showed higher PD-L1 immunoreactivity (p = 0.042). In conclusion, high-grade MCT is associated with an immunosuppressive microenvironment that exhibits elevated RANK/RANK-L signaling and enhanced immune checkpoint immunoreactivity, potentially facilitating intratumorally immune escape. These biomarkers show promise as clinical indicators of disease progression and might response to immunotherapy in dogs with high-grade MCTs, thus emphasizing their importance for guiding treatment decisions and improving outcomes.
RESUMEN
Cutaneous horn is a skin disease with low incidence and few citations in the literature. This report describes a dog with multiple cutaneous lesions of papillomatosis and one giant cutaneous horn on the face. Two sessions of cryotherapy achieved complete remission of the lesions.
La corne cutanée est une maladie de la peau à faible incidence et peu citée dans la littérature. Cet article décrit un chien avec de multiples lésions cutanées de papillomatose et une corne cutanée géante sur la face. Deux séances de cryothérapie ont permis d'obtenir une rémission complète des lésions.
Los cuernos cutáneos son una lesion patológica de baja incidencia y con escasas menciones en la literatura. Este artículo describe un caso de un perro con multiples lesiones cutáneas de papilomatosis y un cuerno cutáneo gigante en la cara. Dos sesiones de crioterapia consiguieron una remisión completa de las lesiones.
O corno cutâneo é uma doença cutânea com baixa incidência e poucas citações na literatura. Este relato descreve um cão com múltiplas lesões cutâneas características de papilomatose e um corno cutâneo gigante na face. Houve remissão completa das lesões após duas sessões de crioterapia.
