Case 249 - Discussion

Uploaded: 2011-12-24, Updated: 2011-12-24

Follicular dendritic cell sarcoma

Interdigitating dendritic cell sarcoma

Location of

Normal Counterpart

Germinal Center

T cell areas (paracortex and interfollicular areas of

lymph node, splenic periarteriolar lymphoid sheaths)

Origin

Mesenchymal

the monocyte-macrophage lineage

Electron microscopy

Numerous long, slender cytoplasmic processes

connected by desmosomes

Complex interdigitating cellular junctions

CD21

+

−

CD35

+

−

S100

−

+

CD23

+

−

Clusterin

+

−

CD1a

−

−

HMB-45

−

−

CD3

−

−

CD20

−

−

CD45

−

+/−

CD68

−

−

Lysozyme

−

−

• CD21: CR2-complement component (3d) receptor 2, and EBV receptor;

• CD23: IgE Fc receptor, FcεRII;

• CD35: erythrocyte complement receptor 1 (CR1, also known as  C3b/C4b receptor and immune adherence receptor)

• Clusterin: designated complement lysis inhibitor (CLI), apolipoprotein J (APOJ), sulfated glycoprotein 2 (SGP2), SP-40 and testosterone-repressed prostate message 2 (TRPM2). A marker of ALCL.