Folliculotropic mycosis fungoides with eosinophilia and CD30+ large‐cell transformation: a case with a fatal outcome presenting with multifocal lesions and leonine facies

Eosinophilia is recognized as a poor prognostic factor in patients with cutaneous T‐cell lymphoma (CTCL). We report a case of folliculotropic mycosis fungoides (FMF) presenting with multiple ulcerative nodular lesions and persistent eosinophilia. Severe facial lesions resulted in a leonine appearance. On histopathological examination, nodular infiltration of large CD30+ large cells was seen. When the previous biopsy specimens were reviewed, marked folliculotropism with atypical lymphocytes was identified in previous specimens 20 years before the blastic transformation. CC chemokine receptor 3 was expressed in tumour cells, whereas CXC chemokine receptor 3 was negative. Expression of interleukin (IL)‐5 was detected in a few mononuclear lymphoid cells. This case demonstrates that T helper (Th)2‐polarized tumour cells may produce Th2 cytokines including IL‐5, which suggests that cytokines and chemokines may contribute to persistent eosinophilia and to recruitment of eosinophils into tumour lesions in advanced FMF.