Carcinoma de células escamosas e esporotricose em felinos - uma abordagem diagnóstica baseada na histopatologia

Squamous cell carcinoma (SCC) is the most common skin tumor in felines, directly related to prolonged exposure to sunlight and the regional climate. Areas with minimal hair coverage, such as the nasal plane and auricular pinna, are most affected, with higher incidence in white-coated cats. Despite its highly invasive nature, metastases associated with SCC are rare. Similar to SCC, other diseases can initially manifest as poorly defined lesions in the facial regions of the animal. These include leishmaniasis, cryptococcosis, feline leproid syndrome, bacterial abscesses, atypical cutaneous mycobacterioses, foreign body granulomas, reactive histiocytosis, and sporotrichosis. The latter is a zoonotic subcutaneous mycosis caused by fungi of the Sporothrix genus, which can present as a subacute or chronic infection. Felines are the animals most frequently affected by sporotrichosis. The infection occurs through the inoculation of the agent via trauma caused by plants, soil and organic matter, or through bites from other infected animals, especially domestic cats. To establish the appropriate treatment in suspected cases, accurate diagnosis is necessary, especially due to the clinical similarity between these diseases. In this context, histopathology stands out as an essential tool for accurate diagnostic analysis, enabling differentiation between clinically similar conditions and ensuring proper therapeutic interventions. This study aimed to report the case of a mixed-breed feline with a history of nasal plane lesions that was treated for sporotrichosis and, upon histopathological examination of the lesion, the diagnosis of SCC was established with no presence of Sporothrix fungi.