Canine Cutaneous Epitheliotropic T-Cell Lymphoma with Vesiculobullous Lesions Resembling Human Bullous Mycosis Fungoides

The study described a 13-year-old male Golden Retriever mix with canine cutaneous epitheliotropic T-cell lymphoma presenting vesiculobullous lesions similar to human bullous mycosis fungoides. The dog exhibited significant weight loss and respiratory distress. Histopathology revealed large CD3+ neoplastic lymphocytes infiltrating the dermis and epidermis, with bullous lesions containing neutrophils and neoplastic cells. Clonal rearrangement analysis confirmed that skin and lung lesions originated from the same neoplastic T-cell population. The findings suggested that vesiculobullous lesions should be included in the clinical spectrum of canine cutaneous epitheliotropic T-cell lymphoma.