Ki-1-positive cutaneous large cell lymphoma of T cell type: report of an indolent subtype.
T cell lymphomas that demonstrate skin involvement include not only mycosis fungoides and Sézary syndrome but also a wide variety of other T cell neoplasms. Whether any specific clinicopathologic associations exist for nonmycosis fungoides/Sézary syndrome cutaneous T cell lymphomas is not known, and whether they represent distinct entities or a spectrum of a similar disease process also is not known. We describe a patient with a localized cutaneous large cell lymphoma with a Ki-1-positive "aberrant" T helper/inducer phenotype. Clonal rearrangement of the T cell receptor gene was documented. Although these histologic characteristics and immunophenotype are usually associated with high-grade lymphomas, the patient appears clinically to have a much less aggressive neoplasm. The possible relationship of this overt lymphoma to lymphomatoid papulosis is discussed.