Erythema elevatum diutinum with rare distribution as a first clinical sign of non-Hodgkin's lymphoma: a novel association?

We present a case of a 78-year-old man with erythema elevatum diutinum as a first clinical sign of non-Hodgkin's lymphoma. The patient developed erythema elevatum diutinum with an unusual distribution involving the trunk. Erythema elevatum diutinum is a rare dermatosis that is considered to be a localized, low-grade form of leukocytoclastic vasculitis associated with neoplastic, autoimmune and infectious processes. It is probably mediated by immune complexes. Recent studies report hematological disease as the most common factor associated with erythema elevatum diutinum. Many hematological diseases, such as myeloma, myelodysplastic syndrome and immunoglobulin (Ig)A monoclonal gammopathy, have been reported in association with erythema elevatum diutinum, but none with IgM monoclonal gammopathy and only one with malignant lymphoma. We would like to add IgM monoclonal gammopathy and non-Hodgkin's lymphoma as one of the diseases associated with erythema elevatum diutinum considering that the activity of erythema elevatum diutinum and non-Hodgkin's lymphoma fluctuated in parallel in the present case.