title: CD8-positive primary cutaneous anaplastic large T-cell lymphoma (PCALCL): case report and review of this unusual variant of PCALCL.
abstract: Primary cutaneous anaplastic large T-cell lymphoma (PCALCL) is a well-defined CD30-positive lymphoproliferative disorder with relatively good prognosis and response to treatment. We describe a case of PCALCL expressing CD8. The patient is a 57-year-old man that clinically presented with an ulcerated nodule in his left middle finger. Histopathologic sections showed an ulcerated epidermis with a diffuse lymphocytic infiltrate in the superficial dermis with focal epidermotropism. The large cohesive atypical cells were admixed with a reactive infiltrate composed of neutrophils, eosinophils, and small lymphocytes. Immunohistochemical studies showed the tumor cells to be strongly positive for CD8, CD30, and TIA-1, focally positive for CD3, and negative for CD4, CD20, CD56, Anaplastic Lymphoma Kinase (ALK-1), and HSV. Epstein-Barr virus by in situ hybridization was negative. The diagnosis of a CD8+ PCALCL was confirmed. There is limited precedent literature regarding CD8-positive PCALCL and this case falls within the clinical and histopathologic spectrum of CD30+ lymphoproliferative disorders. CD8/CD30 coexpression is rare in PCALCL and may have important clinical and prognostic implications. To the best of our knowledge there are only 4 previously reported cases describing similar findings.
authors.affiliation: Department of Dermatopathology, Medical College of Wisconsin, Milwaukee, WI, USA. jplaza@mcw.edu
authors.forename: Jose A
authors.initials: JA
authors.lastname: Plaza
authors.forename: Pablo
authors.initials: P
authors.lastname: Ortega
authors.forename: James
authors.initials: J
authors.lastname: Lynott
authors.forename: Michael
authors.initials: M
authors.lastname: Mullane
authors.forename: Steve
authors.initials: S
authors.lastname: Kroft
authors.forename: Horatiu
authors.initials: H
authors.lastname: Olteanu
mesh_terms: D001706:Biopsy; D018414:CD8-Positive T-Lymphocytes / Q000473:pathology*; D006801:Humans; D017728:Lymphoma, Large-Cell, Anaplastic / Q000145:classification / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012878:Skin Neoplasms / Q000145:classification / Q000473:pathology*; D012883:Skin Ulcer / Q000473:pathology