Follicular lymphoma is the most common of the indolent non-Hodgkin's lymphomas, and the second most common form of non-Hodgkin's lymphomas overall.
It is defined as a lymphoma of follicle center B-cells (centrocytes and centroblasts), which has at least a partially follicular pattern. It is positive for CD10, and usually negative for CD5.
There are several synonymous and obsolete terms for this disease, such as CB/CC lymphoma (Centroblastic and Centrocytic lymphoma), nodular lymphoma and Brill-Symmers Disease.
The tumor is composed of follicles containing a mixture of
centrocytes or cleaved follicle center cells, "small cells", and centroblasts or large noncleaved follicle center cells, "large cells".
These follicles are surrounded by non-malignant cells,
mostly T-cells. In the follicles, centrocytes typically predominate;
centroblasts are usually in minority.
According to the WHO criteria, the disease is
morphologically graded into:
- grade 1 (<5 centroblasts per high-power field (hpf))
- grade 2 (6-15 centroblasts/hpf)
- grade 3 (>15 centroblasts/hpf).
Grade 3 is further subdivided into:
- grade 3a (centrocytes still present)
- the rare grade 3b (the follicles consist almost entirely of
centroblasts)
The clinical relevance of this grading system is debated,
although grades 1, 2 and 3a can be treated as an indolent disease, while
grade 3b is an aggressive disease.
Occasional cases may show
plasmacytoid differentiation or foci of marginal zone or monocytoid
B-cells.
Median survival is around 10 years, but the range is wide, from less
than one year, to more than 20 years. Some patients may never need
treatment.
Of all cancers involving the same class of blood cell, 22% of cases are
follicular lymphomas.
Further Reading
This article is licensed under the Creative Commons Attribution-ShareAlike License.
It uses material from the Wikipedia article on
"Follicular lymphoma"
All material adapted used from Wikipedia is available under the terms of the
Creative Commons Attribution-ShareAlike License.
Wikipedia® itself is a registered trademark of the Wikimedia Foundation, Inc.