Case 51 - Discussion

Uploaded: 2008-03-28, Updated: 2008-03-28

 

Positive: CD21, CD35 and clusterin

Negative: Pan-CK, CK-LMW, CD45, chromogranin, synaptophysin, and CD57.

Diagnosis: Follicular dendritic cell sarcoma

Follicular dendritic cell sarcoma vs. Interdigitating dendritic cell sarcoma

 

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.

Reference

  • Am J Clin Pathol. 2007 Nov;128(5):776-82.

  • Am. J. Hematol. 82:924–928, 2007

  • USCAP, Denver, 2008. Abstract 1169 and 1175
 

Summarized by Zenggang Pan, MD, PhD