SUBCUTANEOUS CRYSTAL-STORING HISTIOCYTOSIS ASSOCIATED WITH LYMPHOPLASMACYTIC LYMPHOMA (IMMUNOCYTOMA)

A case of massive crystal-storing histiocytosis with extensive involve ment of the subcutaneous adipose tissue in a 61-year-old caucasian wom an with a lymphoplasmacytic lymphoma (immunocytoma) in transformation to a large cell lymphoma is presented. Paraffin-section immunohistoche mistry demonstrated a monoclonal IgM/kappa immunphenotype of the lymph oma cells and revealed IgM/kappa and, to a lesser extent, IgG/lambda i n the crystal-containing histiocytes. Ultrastructurally, the electron dense intracytoplasmic crystals had variable shapes, were occasionally membrane-bound and measured up to 6 mu m. The findings are briefly di scussed.