CD30+lymphoproliferative disorder: primary cutaneous anaplastic large celllymphoma followed by lymphomatoid papulosis

CD30+ large anaplastic lymphoid cells are seen in anaplastic large cell lym phoma (ALCL), and also in lymphomatoid papulosis (LyP) and other lymphoprol iferative disorders. It can be difficult precisely to categorize these diso rders with CD30+ cells. We report a case of primary cutaneous CD30+ ALCL wi th systemic metastases in whom the clinical disease subsequently evolved in to LyP. The patient was initially administered cisplatin and etoposide and made a good response. Eighteen months later, recurrent, self-healing cutane ous small nodules appeared around the original tumour site without any syst emic involvement. Histopathological examination of the recurrent lesions re vealed infiltration with a mixture of cells that included neutrophils, eosi nophils and CD30+ large anaplastic cells cytologically identical with those in the primary lesion. The anaplastic cells in both the primary and recurr ent lesions were positive for monoclonal antibodies CD30, CD25 and a monocl onal antibody directed against the chimeric protein p80(NPM-ALK). These obs ervations suggest the possibility that the ALCL and the subsequent LyP repr esent different clinical manifestations of proliferation of the same clone.