Case of CD8 and CD30 positive Pagetoid Reticulosis

Summary: Pagetoid Reticulosis (PR), a rare variant of mycosis fungoides, is a cutaneous T-cell lymphoma often presenting as a hyperkeratotic plaque on the extremities in adults or children. It frequently remains undiagnosed for years. Treatment options include surgical excision, local radiation, electron beam therapy, PUVA baths, and wound care, with favorable outcomes (Haghighi et al., 2000). Histopathologically, PR is characterized by lymphocytic epidermotropism in a hyperplastic epidermis, with atypical lymphocytes confined to the epidermis and a reactive dermal infiltrate. Immunohistochemical findings often reveal positivity for CD4, CD8, and CD30; CD8 and CD30 positivity may correlate with an indolent course (Jacyk et al., 2007; Mourtzinos et al., 2009). A 33-year-old woman with no significant medical history presented with a solitary, asymptomatic crusty lesion on her right thigh for one year. Shave biopsy revealed irregular epidermal hyperplasia infiltrated by malignant mononuclear cells with nuclear pleomorphism, mitoses, and epidermotropism. Immunohistochemistry showed CD3 and CD8 positivity, weak CD30 positivity, and staining for CD2, CD5, and granzyme, with CD7 and CD56 loss. Further staining showed lesional cells stained positive for alpha/beta and negative for gamma/delta. The solitary lesion and CD8-positive, CD4-negative profile with weak CD30 positivity favored a diagnosis of pagetoid reticulosis (Woringer-Kolopp variant).