Intravascular Large B-Cell Lymphoma

Supplemental Studies

Leukocyte common antigen (LCA) positive
Predominantly B lineage
- Probably at least 95% B
- CD5 co-expression reported 22-75%
- MUM1 positive in 90%
- BCL2 expression reported in 98% (no bcl2 rearrangement)
- BCL6 expression reported in 22%
- CD10 expression reported in 13-22%
- No CD43 co-expression reported
Infrequent T lineage cases
Single case with NK phenotype
Very rare cases with true histiocytic phenotype
Endothelial markers negative
Lack expression of adhesion molecules CD29 (beta-1 integrin) and CD54 (ICAM-1), may explain intravascular growth
Prostatic acid phosphatase positive
- Reported in 5/5 autopsy cases
- Also present in serum
- Prostate specific antigen negative

PCR may detect marrow or peripheral blood involvement in cases negative by light microscopy
Immunoglobulin gene rearrangements detectable in most cases
T receptor gene rearrangements detectable in T lineage cases
bcl2 gene rearrangements not detectable
EBV detectable by PCR in 7/9 cases but fewer by in situ hybridization