EXPRESSION OF PROLIFERATING CELL NUCLEAR ANTIGEN IN CUTANEOUS MALIGNANT-LYMPHOMAS AND LYMPHOID INFILTRATES

Paraffin-embedded tissue of skin biopsy specimens taken retrospectivel y from 24 patients with cutaneous malignant lymphomas (CML) and 8 pati ents with cutaneous lymphoid infiltrates (CLI) and other dermatoses we re studied retrospectively with PC10 immunostaining. The results show a statistical significant difference among PC10 indices for cutaneous genuine histiocytic lymphoma (CGHL), cutaneous germinal center cell-de rived lymphomas (CGCCL), cutaneous peripheral T-cell lymphomas (CPTL), non-mycosis fungoides (MF) and Sezary's syndrome (SS), and MF when co mpared with those for CLI. There is a linear relationship between PC10 index and square root of PC10 density, both of which seem to have a p arallel relationship to the severity of malignancy in CML. The nuclear volume of the positive tumor cell or lymphocyte with PC10 immunostain ing may be also useful in differentiating CML from CLI.