PRIMARY CUTANEOUS MONOMELIC B-CELL LYMPHOMA

Background Cutaneous B cell lymphomas, especially when appearing as a monomelic papulonodular eruption, are rare. Patient Ms H. 87-year-old, consulted for a papulonodular eruption of the left lower limb which d eveloped during the past 5 months. This limb had bren the site of a ly mphedema since a traumatism 8 years ago. Histopathological analysis an d immunostaining of a nodule showed that it was a large cell lymphoma of follicular stem cells. There was no extracutaneous involvement and the patient was successfully treated with radiotherapy. Two months aft er she completed radiotherapy a cutaneous relapse on the trunk and the upper limbs was treated with cyclophosphamide-vincristine-prednisone chemotherapy. Discussion Lymphedema probably played a role in the gene sis of this lymphoma presumably by reducing the local immune response. It may have harmed endothelial cells and maintained an antigenic stim ulation leading first to lymphocyte hyperplasia and eventually to a tr ue lymphoma, in the same way this has been proved for some MALT lympho mas.