Pagetoid reticulosis Woringer-Kolopp type, a particular variant of mycosis fungoides: a case report.

According to the definition of WHO, pagetoid reticulosis (PR) is characterized by the presence of unique skin lesion in the shape of patches or plaques caused by the proliferation of atypical T-cells in epidermis. We report the case of a 50-year-old female, presenting a 50×65 mm erythematous scaly patch, well-defined, slightly infiltrated, discrete polycyclic, on the right buttock, which appeared and developed in about 6-8 months. The clinical and dermatoscopic aspects suggested a Bowen's disease. A skin biopsy was performed. The histological examination of the pieces confirmed the presence of monoclonal lymphoid infiltrate with obvious phenomena of epidermotropism. Immuno-phenotypically the tumoral cells express intensively CD3 and CD8 and focally CD4. Surgical excision was performed without radiotherapy and chemotherapy. The patient was followed-up for 42 months without local relapses, distant lymph nodes or visceral metastases. Microscopic aspect of the lesion corresponds to stage I-II of mycosis fungoides (MF) (patches or plaques); the diagnosis was PR Woringer-Kolopp type. The most recent classification of skin lymphomas (WHO, 2008) confirms that the immunohistochemical profile of T-cells can be CD4+ and CD8- or CD4- and CD8+, and frequently CD30+, in contrast to the classical versions of MF. Pagetoid reticulosis type Woringer-Kolopp, a rare particular variant of mycosis fungoides, is suspected in cases with unique, distinctive lesion and confirmed only by histological immunohistochemistry. Treatment consists of surgical excision of the lesion with long follow-up.