Primary Follicular Lymphoma of the Duodenum Is a Distinct Mucosal/Submucosal Variant of Follicular Lymphoma: A Retrospective Study of 63 Cases

Abstract

These findings characterize primary FL-D as a remarkably indolent FL variant, which, even left untreated, does not develop tumorous growth, very rarely disseminates (two of 63 patients) and does not transform to high grade disease. A watch and wait approach appears to be the most sensible strategy.

Early lymphoid lesions: conceptual, diagnostic and clinical challenges

“…[46][47][48] In view of its unique clinicopathological features, primary intestinal (duodenal) follicular lymphoma (DFL) was recognized as a separate variant of FL in the 2008 World Health Organization classification. 5 It shares many features with FLIS/FLBUS in terms of its usually benign natural history.…”

Iodine-131 Rituximab Radioimmunotherapy: Durable Control of Follicular Lymphoma

“…These patients continue to be asymptomatic at 44, 55, and 60 months follow-up post 131I-rituximab RIT and four doses of maintenance rituximab, and none have required further treatment. This cohort has achieved excellent response, but this should be interpreted with caution as it seems to be a remarkably indolent FL variant more likely than nodal FL to present with early stage disease [20]. Duodenal FL has different features from nodal FL, including grade 1/2 histology, no marginal zone or plasmacytic differentiation, no reactive germinal centres, and the t(14;18)(q32;q21) positive B-cells do not acquire further karyotypic changes thus they have a low malignant potential [20].…”

“…This cohort has achieved excellent response, but this should be interpreted with caution as it seems to be a remarkably indolent FL variant more likely than nodal FL to present with early stage disease [20]. Duodenal FL has different features from nodal FL, including grade 1/2 histology, no marginal zone or plasmacytic differentiation, no reactive germinal centres, and the t(14;18)(q32;q21) positive B-cells do not acquire further karyotypic changes thus they have a low malignant potential [20]. The gene expression profile shows upregulation of Chemokine ligand 20 (CCL20) and mucosal vascular addressin cell adhesion molecule 1 (MAdCAM-1) which is downregulated in nodal FL and may play a role in molecular pathogenesis which is presently unclear [21].…”

Extranodal and splenic small B-cell lymphoma

“…41,42 Morphologically the infiltrate consists of either a single abnormal follicle or small groups of neoplastic follicles, which may be limited to the mucosa or extend more deeply through the wall (Figure 2). The immunophenotype of GI follicular lymphoma is identical to the nodal counterpart with expression of pan-B-cell markers, CD10 and BCL6 (Figure 2).…”