Canine And Feline Cutaneous Lymphocytosis: Reactive Process Or Indolent Neoplastic Disease?
December 2021
cutaneous lymphocytosis alopecia erythema scales dermal infiltrate lymphocytes CD3+ infiltrate polyclonal lymphocytes CD20+ lymphocytes BCR clonal rearrangements TCR clonal rearrangements hair loss skin redness skin scales skin infiltrate immune cells T cells B cells B cell receptor clonal rearrangements T cell receptor clonal rearrangements
TLDR Cats likely have a reactive skin condition, while dogs may have a more complex, possibly cancerous one.
Cutaneous lymphocytosis (CL) in dogs and cats presents with alopecia, erythema, and scales, and is characterized by a dermal infiltrate of small to medium-sized lymphocytes. In a study of 19 cats and 10 dogs, cats consistently showed a CD3+ infiltrate and polyclonal lymphocytes, with a median survival of 1080 days, suggesting a reactive nature of the disease. Dogs, however, exhibited a mixture of CD3+ and CD20+ lymphocytes in some cases, with BCR and TCR clonal rearrangements, indicating a more variable and potentially neoplastic nature, and had a shorter, more variable clinical course. The findings support a reactive process in cats and a more complex, possibly neoplastic process in dogs.
