lymphomatoid papulosis


lym·pho·ma·toid pa·pu·lo·sis

a chronic papular and ulcerative variant of pityriasis lichenoides et varioliformis acuta characterized by dermal perivascular infiltration by atypical T lymphocytes suggestive of a lymphoma; it is usually benign, but transformation to lymphoma has been reported.

lymphomatoid papulosis

A roccidig papular eruption of the skin that histologically resembles lymphoma; although most lesions behave in an indolent fashion, gene rearrangement studies demonstrate a T-cell clonal expansion (10–20% evolve to T-cell lymphoma); acral and truncal distribution.
DiffDx, benign
Arthropods, infectious granulomas (TB, fungal), leukocytoclastic vasculitis, PLEVA (pityriasis lichenoides et variolis acuta), pseudolymphoma, scabies.
DiffDx, uncertain
Langerhans cell histiocytosis.
DiffDx, malignant
Acute lymphoblastic lymphoma, Merkel cell carcinoma, mycosis fungoides.

lymphomatoid papulosis

 A benign recurring papular eruption of the skin which histologically resembles lymphoma; although most lesions are indolent, gene rearrangement studies demonstrate a T cell clonal expansion; 10-20% evolve toward T-cell lymphoma