title: Marginal zone B-cell lymphoma in children and young adults.
abstract: We describe the clinicopathologic findings of 48 cases of marginal zone B-cell lymphoma (MZL) in children and young adults, a disease that has been recognized previously only rarely in this age group. Patients ranged in age from 2 to 29 years, with pediatric patients (< or =18 years) comprising 52% of the cases. As in adults, both primary nodal (N) and extranodal (E) MZL were observed. However, primary NMZL comprised the majority of the cases (67%) and demonstrated distinctive clinical and histologic features. NMZL occurred most commonly in young males (median 16 years, male/female ratio 5.4:1), with no underlying disease, presenting as localized adenopathy (90% stage I), with excellent prognosis and low rate of recurrence. In contrast, EMZL were much less common, and patients were older (median 24.5 years), with only a slight male predominance (male/female ratio 1.2:1). Most patients had localized disease (73% stage I) with excellent prognosis and infrequent recurrences. In addition, an association with autoimmune disease was observed in 19% of the EMZL. Both primary NMZL and EMZL in young patients shared similar morphologic and immunophenotypic findings to those described in adults and were monoclonal B-cell proliferations with monoclonality demonstrated in 94% of the cases. A common morphologic feature in NMZL was disruption of residual follicles resembling progressive transformation of germinal centers (PTGC), observed in 66% of the cases. Although the precise relationship of primary NMZL and the PTGC-like changes is unclear, it is possible that NMZL arises in a background of PTGC, as florid PTGC often occurs in young males. We conclude that EMZL in children and young adults are similar to EMZL of mucosa-associated lymphoma tissue occurring in older patients. However, pediatric NMZL appear to have distinctive clinical and histologic features.
authors.affiliation: Hemopathology Section, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute/NIH, 10 Center Drive, Bethesda, MD 20892, USA.
authors.forename: Lekidelu
authors.initials: L
authors.lastname: Taddesse-Heath
authors.forename: Stefania
authors.initials: S
authors.lastname: Pittaluga
authors.forename: Lynn
authors.initials: L
authors.lastname: Sorbara
authors.forename: Mary
authors.initials: M
authors.lastname: Bussey
authors.forename: Mark
authors.initials: M
authors.lastname: Raffeld
authors.forename: Elaine S
authors.initials: ES
authors.lastname: Jaffe
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D016130:Immunophenotyping; D008198:Lymph Nodes / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000473:pathology*; D008297:Male