Spectrum of primary cutaneous CD30 (Ki-1)-positive lymphoproliferative disorders. A proposal for classification and guidelines for management and treatment.

Primary cutaneous CD30 (Ki-1)-positive, large cell lymphomas (LCLs) represent a recently recognized group of cutaneous T-cell lymphomas with a favorable prognosis. The characteristic features of this cutaneous lymphoma are reviewed, differences with primary noncutaneous CD30+ LCLs emphasized, and its relation with other CD30+ cutaneous lymphoproliferative disorders, in particular lymphomatoid papulosis, is discussed. These primary cutaneous CD30+ LCLs, lymphomatoid papulosis, and related conditions represent a clinical and histologic continuum. A classification with practical guidelines for the management and treatment of patients within this spectrum of lymphoproliferative disorders is presented.