CD3 and CD20 Coexpression in a Case of Canine Cutaneous Epitheliotropic T-Cell Lymphoma (Mycosis Fungoides).
A 14-year-old female spayed Dachshund was presented with generalized scaling, erythema, pruritus, poor quality of hair coat, and progressive weight loss. Cutaneous epitheliotropic T-cell lymphoma (CETCL) was suspected. Skin biopsies were suggestive of CETCL. However, immunohistochemistry revealed the presence of numerous CD20+ and CD3+ cells. Clonality assay demonstrated a clonal T-cell receptor gamma rearrangement and a polyclonal IgH gene rearrangement. Double-label immunofluorescence confirmed coexpression of CD3 and CD20 by neoplastic cells. By double immunohistochemistry, neoplastic cells were CD3+ and PAX5-. The results are compatible with a CD3+, CD20+ CETCL. Coexpression of CD20 and CD3 has been recognized in peripheral T-cell lymphomas. Although documented in human CETCL, it has not been reported in canine CETCL. The pathogenetic basis of CD20 expression in mycosis fungoides is explored.
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, Perugia, Italy chiara.brachelente@unipg.it.
C
C
Brachelente
Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA, USA.
V K
VK
Affolter
Centro Veterinario Prati, Viale delle Milizie, Rome, Italy.
A
A
Fondati
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, Perugia, Italy.
I
I
Porcellato
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, Perugia, Italy.
M
M
Sforna
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, Perugia, Italy.
E
E
Lepri
Department of Veterinary Medicine, University of Perugia, Via San Costanzo, Perugia, Italy.
L
L
Mechelli
Faculty of Veterinary Medicine, University of Teramo, Località Piano D'Accio, Teramo, Italy.
L
L
Bongiovanni
D000818:Animals; D018951:Antigens, CD20 / Q000378:metabolism*; D001706:Biopsy / Q000662:veterinary; D017252:CD3 Complex / Q000378:metabolism*; D004283:Dog Diseases / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D004285:Dogs; D004848:Epithelium / Q000378:metabolism / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique / Q000662:veterinary; D007150:Immunohistochemistry / Q000662:veterinary; D016410:Lymphoma, T-Cell, Cutaneous / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D009182:Mycosis Fungoides / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*; D012867:Skin / Q000378:metabolism / Q000473:pathology; D012878:Skin Neoplasms / Q000175:diagnosis / Q000378:metabolism / Q000473:pathology / Q000662:veterinary*
D018951:Antigens, CD20; D017252:CD3 Complex
CD20; CD3; PAX5; T cell; canine; clonality; cutaneous epitheliotropic T-cell lymphoma; double-label immunofluorescence; immunohistochemistry; skin