DZI20-210-Case-20
Persistent scaly plaques involving bilateral arms over 30 years
SKIN, LEFT UPPER DORSAL ARM, PUNCH BIOPSY: Cutaneous T cell lymphoma with gamma/delta phenotype.
IHC: atypical cells are of T-cell lineage (CD3+) with gamma delta T-cell receptor phenotype, largely lack CD4 and CD8 expression, and demonstrate reduced expression of CD2 and CD7. CD56 is negative, and of the cytotoxic markers, only perforin shows weak positivity. The dermal infiltrate appears to be reactive with positivity for BetaF1, subset positivity for CD4 and CD8, and relatively strong expression of PD1, ICOS, PD-L1, and CD25. Adnexotropism or large cell transformation are not seen. Subcutaneous fat is not involved. T-cell receptor gene rearrangement studies demonstrate clonal rearrangement of beta chain. DDX: incipient/evolving cutaneous gamma-delta T-cell lymphoma and mycosis fungoides with gamma-delta phenotype.
December 31, 1969 7:00:00 PM
