This study characterizes the clinicopathological spectrum of lymphoproliferations involving the breast nipple and/or areola. Morphologic, immunohistochemical, molecular-genetic, and clinical features of 58 specimens from 56 patients were analyzed. They were re-diagnosed as cutaneous lymphoid hyperplasia (CLH, n = 44); other benign lymphoid infiltrates (OBLI, n = 8); peripheral T-cell lymphoma, not otherwise specified (n = 1); cases with overlapping features of CLH and B-cell lymphoma (n = 3), one of them composed of spindle cells. Cutaneous lymphoid hyperplasia infiltrates were dense, composed mainly of B cells forming follicles with germinal centers (GC). Cutaneous lymphoid hyperplasia frequently showed features suggesting a malignancy as coalescing follicles with non-polarized germinal centers lacking mantle zones, and smudged infiltrates of lymphoid cells spreading into collagen (often as “Indian files”), smooth muscle, vessel walls, and nerve sheaths. Only two cutaneous lymphoid hyperplasias recurred; otherwise all patients are without disease (mean follow-up 62 months). Monoclonal rearrangement of immunoglobulin heavy chain gene was detected in five, and of T-cell receptor γ gene in two cutaneous lymphoid hyperplasias using polymerase chain reaction (PCR), but the patients fared well too. In 47% of cases Borrelia burgdorferi was detected by polymerase chain reaction and/or serology, of which one was monoclonal. We conclude that cutaneous lymphoid hyperplasia is the most common lymphoproliferation of the breast nipple, rarely recognized clinically, and often overdiagnosed histologically as lymphoma.
From the *Department of Pathology, Medical Faculty Hospital, Charles University, Pilsen, Czech Republic; †Department of Pathology, Radium Hospital, Oslo, Norway and Department of Pathology, Royal University Hospital, Saskatoon, Canada; ‡Department of Pathology, Institute of Oncology, Ljubljana, Slovenia; §Dermatopathologische Gemeinschaftspraxis, Friedrichshafen, Germany; ¶Department of Pathology, Jessenius Medical Faculty and Faculty Hospital, Komensky University, Martin, Slovakia; and ∥Department of Obstetrics and Gynaecology, Medical Faculty Hospital, Charles University, Pilsen, Czech Republic.
This study was supported in part by the Internal Grant Agency of the Czech Ministry of Health (Grant project NR8231-3/2004).
Reprints: Michal Michal, MD, Department of Pathology, Lab. Spec. Diag., Medical Faculty Hospital, Alej Svobody 80, 304 60 Plzeň, Czech Republic (e-mail: firstname.lastname@example.org).