Primary cutaneous large cell anaplastic lymphoma (C-ALCL) and lymphomatoid papulosis (LyP) are cutaneous CD30+ lymphoproliferative disorders (CD30+ LPD). An association with CD30+ LPD and pseudoepitheliomatous hyperplasia has been recognized. Additionally, rare reports of epithelial neoplasms such as keratoacanthomas and squamous cell carcinomas (SCC) occurring in association with both C-ALCL and LyP have been reported. We report two cases of CD30+ LPD with associated epithelial neoplasms; one patient with a primary cutaneous CD30+ LPD and SCC identified within the same lesion, and the other with a keratoacanthoma arising in a lesion of LyP. The pathogenesis of this association is poorly understood although various hypotheses exist. Awareness of the coexistence of these entities will avoid misdiagnosis and incorrect treatment.
Keywords: cutaneous CD30+ lymphoproliferative disorder; keratoacanthoma; lymphomatoid papulosis; primary cutaneous large cell anaplastic lymphoma; pseudoepitheliomatous hyperplasia.
© 2014 The Australasian College of Dermatologists.