Lymphomatoid contact dermatitis has been reported as a reaction to various allergens including nickel (6,7), cobalt naphthenate (8), isopropyl-diphenylenediamine (9), and others. Genotyping has shown clonal rearrangement in some cases. Such cases may be closely related to "clonal dermatitis" some of which develop into overt CTCL (10). Histologically, epidermotropism of lymphocytes and accumulations of CDla-positive Langerhans cells may be found (Figs. 4 and 5).
Evolution into cutaneous T-cell lymphoma was observed in four patients with long-standing chronic contact dermatitis (11) present for up to 15 years before clinically and histologically verified mycosis fungoides occurred. Contact allergy was confirmed in these cases by patch testing with sensitization against nickel, potassium dichromate, and formaldehyde. These observations may suggest that at least in some cases, CTCL may be caused by chronic antigenic immunostimulation (12).
Was this article helpful?