Sean Klepper M.D.
Artur Zembowicz M.D....
- Presents as solitary or grouped papules, plaques or tumors
- Most common on the scalp, forehead and back
- Good prognosis
- Nodular or diffuse infiltrate occupying the entire dermis and sometimes extending into the subcuataneous fat
- Follicle formation may or may not be seen in the nodular pattern, and is absent from the diffuse pattern.
- The infiltrate consists of a mixture of centrocytes (small lymphocytes with cleaved nuclei) and centroblasts (large lymphocytes with prominent nucleoli), with the centrocytes typically predominating in the nodular pattern.
- If follicle formation is present, the neoplastic follicles are surrounded by reactive T-cells and histiocytes, with foci of interfollicular neoplastic B-cells.
- The diffuse pattern may resemble diffuse large B-cell lymphoma, but the prognosis remains excellent, and the diagnosis should still be follicle center lymphoma.
- The neoplastic lymphocytes stain for pan-B-cell markers and usually for bcl-6.
- CD10 may or not be positive, in contrast to systemic follicular lymphoma, in which it is positive.
- Also in contrast to systemic follicular lymphoma, the (14;18) translocation is almost always absent.