CD20 Negative Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type with Rapidly Progressing Skin Lesions

Abstract

A 95-year-old man came with violaceous nodular skin lesions of the left shin. The lesions were not painful or pruritic but progressed rapidly over the 3 months. Fever, night sweats, weight loss, and other systemic symptoms were absent. Shave biopsy of the lesion revealed the cells negative for CD20 but positive for BCL2, BCL6, FOX-P1, and CD10. PET/CT showed high uptake in the left leg and a sizeable hypermetabolic lymph node in the left pelvis. The patient was started on rituximab treatment as a single agent. This report highlights some of the diagnostic and treatment difficulties in CD20 negative lymphomas and the importance of a multidisciplinary approach in those cases.

Keywords

• diffuse large B-cell lymphoma, leg type (DLBCL-LT)
• primary cutaneous diffuse large B-cell lymphoma
• leg type (PCDLBCL-LT)
• positron emission tomography/computed tomography (PET/CT)
• cluster of differentiation (CD)
• B-cell lymphoma 2 (BCL2)