CUTANEOUS B-CELL LYMPHOMA CONSISTING OF LARGE CLEAVED CELLS WITH MULTILOBATED NUCLEI

A 65-year-old man was seen at the Ushioda Hospital in Au-gust 1989, because of a 1-month history of a tumor on the scalp. The tumor was excised and the diagnosis was malig-nant lymphoma. The patient was then referred to our de-partment in September 1989. Several nut-sized lymph nodes wvepa-b and m-fepa for 2 months. Since then, the patient has been free of disease up to the time of writing, July 1992, a period of 2.5 years. Biopsy samples taken from the tumor on the scalp showed a monomorphous infiltrate of large lymphoid cells throughout the entire dermis and subcutis, with a definite clear zone (Fig.1). A high-power view showed diffuse large lymphoid cell infiltration. Numerous mitotic figures were also seen. The lymphoid cells had multilobated nuclei and distinct nucleoli (Fig. 2). Monoclonal antibodies such as Leui (CD5), Leu2a (CD8), Leu3a (CD4), Leu4 (CD3), MT-1 (CD43), Leu14 (CD22), LN1 (CDw75), and Leu26 (CD20), and polyclonal antibodies such as anti-kappa, anti-lambda, anti-IgG, anti-lgA, anti-IgM, and anti-lgD were purchased from commercial sources. Optimal dilutions of the monoclonal antibodies and heteroantisera were assessed beforehand by titration on suitable tissue samples. The antigens recognized by the monoclonal anti-bodies and heteroantisera were investigated by either the avidin-biotin peroxidase complex (ABC) method on cryostat sections or the peroxidase-antiperoxidase complex (PAP) method on paraffin sections, as described elsewhere.¹ The immunologic properties of the infiltrating cells were determined using skin biopsied in August 1989, and October 1989. Large lymphoid cells, which formed the major popu-lation of infiltrating cells, were positive for CD20, CD22, and HLA-DR and negative for CD3, CD4, CD43, and CD45RO. From these findings the patient was diagnosed as hav-ing primary cutaneous B-cell lymphoma, diffuse large non-cleaved cell type, as classified by the Working Formulation.²