T-helper cell phenotype expression in cutaneous lesions of angioimmunoblastic T-cell lymphoma

Background: Angioimmunoblastic T-cell lymphoma (AITL) is a common type of peripheral T-cell lymphoma. AITL can be missed until lymphadenopathy develops in patients initially presenting with skin lesions, as skin biopsy may lack conclusive findings. The expression of follicular helper T-cell (THF) markers in the skin can be an important diagnostic clue. We present a case of AITL with skin lesions positive for CD10 and dim PD-1 T cells, with the purpose of highlighting the potential for diagnosing cutaneous AITL via skin biopsy.