Follicular Dendritic Cell Sarcoma : Molecular Genetics

Comments:
Follicular dendritic cell sarcomas (FDCS) have no B-cell or T-cell gene rearrangements and carry no recurring cytogenetic abnormalities in most cases. The liver and splenic FDCS with resemblance to inflammatory pseudotumor show EBV-coded RNA (EBER). A small percentage of FDCS have recurrent BRAF V600E mutation, similar to that seen in histiocytic sarcoma and Langerhans cell histiocytosis, although at a lower frequency.

The image shows a proliferation of uniform spindled cells in whorled, fascicular, and storiform configurations, admixed with small lymphocytes.