Follicular lymphoma (FL) is the most common of the indolent non-Hodgkin's lymphomas. It is defined as a lymphoma of follicle center B-cells (centrocytes and centroblasts), which has at least a partially follicular pattern. more...
The tumor is composed of follicle center cells, usually a mixture of centrocytes (cleaved follicle center cells, "small cells") and centroblasts (large noncleaved follicle center cells, "large cells"). Centrocytes typically predominate; centroblasts are usually in the minority, but by definition are always present. Rare lymphomas with a follicular growth pattern consist almost entirely of centroblasts. Occasional cases may show plasmacytoid differentiation or foci of marginal zone or monocytoid B-cells.
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