Research Note: Differentiating Cutaneous Epitheliotropic Lymphoma

CD20 is predominantly a B-cell marker expressed before B cells differentiate into plasma cells. CD20 expression has rarely been reported in cutaneous epitheliotropic T-cell lymphoma. This retrospective study aimed to characterize the baseline frequency and prognostic value of CD20<sup+sup> staining in cutaneous epitheliotropic T-cell lymphoma. No significant correlation was identified between CD20<sup+sup> staining characteristics and median survival time from onset of signs or diagnosis. Cutaneous epitheliotropic T-cell lymphoma had a higher instance of CD20 positivity (54%) than previously documented. CD20 staining may therefore be unsuitable for differentiating between T- and B-cell cutaneous epitheliotropic lymphoma. However, these results suggest that anticanine CD20 monoclonal antibodies may have therapeutic value in patients with cutaneous epitheliotropic T-cell lymphoma.