Staining Proliferation of FDC cells is characteristic of many neoplastic conditions including follicular hyperplasia, follicular lymphoma, nodular lymphocyte predominate Hodgkin’s disease and angioimmunoblastic T-cell lymphoma. Despite finally being recognized as its own disease in 1986, diagnosis of FDCS is still difficult. FDC cells are large, contain two nuclei, and form clusters with lymphocytes making them difficult to distinguish in staining. These cells are best visualized with immunostaining using the FDC markers CD21, CD35, R4/23, clusterin, and KiM4p. Marker analysis has also led to debate over the origin of the cell type; it coexpresses CD45, a leukocyte common antigen, and CD15, a monocyte common antigen. Because of the debate and difficulty of staining, pathologic diagnosis often requires morphologic, cytochemical and electron microscope analysis as well. Cellular mutations Cellular abnormalities found within the FDCS tumor have been exploited for diagnostic purposes. Characteristically, FDCS have mircotubuloreticular structures (MTRS) and increased levels of intracellular clusterin. MTRS contribute to microtubule formation of many structures, including the mitotic spindle, during cell division. This contributes to many of the hallmarks of cancer, including proliferative signaling, growth activation, and replicative immortality. Clusterin is a heterodimeric protein that aids in the clearance of cellular debris and is involved with apoptosis. Clusterin can be stained to help distinguish FDCS and is involved in the many important cancer hallmarks, including resistance to cell death and evading growth suppressors.
Follicular dendritic cell sarcoma
Langerhans cell sarcoma
Thymic carcinoma
Gray zone lymphoma
Unicentric Castleman disease
Follicular lymphoma
Pleomorphic T-cell lymphoma
Nodal marginal zone B cell lymphoma