Primary Cutaneous Diffuse Large B-Cell Lymphoma – a Case Report

In 2005, the World Health Organization - European Organization for Research and Treatment of Cancer (WHOEORTC) classified cutaneous B-cell lymphomas into 4 categories: primary cutaneous marginal zone B-cell lymphoma (PCMZL), primary cutaneous follicle center lymphoma (PCFCL), primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT), and primary cutaneous diffuse large B-cell lymphoma, other (PCDLBCL-O). The absence of evident extra-cutaneous disease is a necessary condition for the diagnosis of primary cutaneous B-cell lymphomas, because they have a completely different clinical behavior and prognosis from their nodal counterparts. PCDLBCL-O basically represents a morphological variation, lacking the typical features of PCDLBCLLT, neither confirming the definition of PCFCCL, but on the clinical ground, its behavior seems at least to partially overlap the indolent course of PCFCCL. In fact, the present WHO lymphoma classification from 2008 overcame the previous WHO-EORTC classification, including at least a part of PCDLBCL-O within the spectrum of PCFCCL. However, owing to the rarity and heterogeneity of the PCDLBCL-O, the precise clinicopathological characteristics have not been well characterized and the optimal treatment for this group of lymphomas is yet to be defined. Nevertheless, dermatologists and pathologists should be aware of this entity in order to avoid unnecessary aggressive treatment. We present a case of a 46-year-old Caucasian male with one large round-shaped tumor and a few scattered nodules localized on the back. The histopathological features of the lesion corresponded to PCDLBCL-O. The patient follow-up showed that he was disease-free three months after surgical excision of the lesions and adjuvant local radiotherapy. No additional therapy was introduced, including chemotherapy with rituximab, cyclophosphamide, doxorubicin hydrochloride, oncovin, prednisolone (R-CHOP).