Cutaneous Waldenstrom's macroglobulinemia with "deck-chair" sign treated with cyclophosphamide.

Specific skin lesions are rare in Waldenstrom's macroglobulinemia (WM). We report a case of a 58-year-old man who presented macules, papules, and an erythema of the trunk with the "deck-chair" sign revealing the relapse of WM. Histologic and immunohistochemical examinations confirmed that cutaneous lesions were related to specific infiltration with neoplastic cells. Remission of both skin lesions and immunological abnormalities was obtained with oral cyclophosphamide.