title: Neoplastic erythema nodosum.
abstract: We performed immunohistologic studies on a 75-year-old white woman with erythema nodosum (EN) and a systemic lymphoma. A skin biopsy specimen from an EN lesion showed lobular and septal pannicular infiltration by atypical lymphocytes. The cutaneous lymphocytic infiltrate was composed of a monoclonal population of B cells with lambda light chains. Atypical lymphocytes were also seen in the peripheral blood, and flow cytometry showed a predominance of the same phenotype of B cells with lambda light chains. Chemotherapy for systemic B-cell lymphoma resulted in the simultaneous resolution of EN and the lymphoma. This is the first documentation of EN representing direct cutaneous invasion by a B-cell lymphoma.
authors.affiliation: Department of Dermatology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA.
authors.forename: L Y
authors.initials: LY
authors.lastname: Matsuoka
mesh_terms: D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D001402:B-Lymphocytes / Q000473:pathology; D004893:Erythema Nodosum / Q000473:pathology*; D005260:Female; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000032:analysis; D007146:Immunoglobulin lambda-Chains / Q000032:analysis; D007868:Leg Dermatoses / Q000473:pathology*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000473:pathology*; D009361:Neoplasm Invasiveness; D015434:Panniculitis / Q000473:pathology; D012878:Skin Neoplasms / Q000473:pathology*
chemical_list: D015703:Antigens, CD; D018941:Antigens, CD19; D000944:Antigens, Differentiation, B-Lymphocyte; D007147:Immunoglobulin Light Chains; D007146:Immunoglobulin lambda-Chains