Peripheral T Cell Lymphoma Unspecified
Supplemental Studies
Immunohistology
- Non-lineage specific markers
- CD30+ 30-60%
- Cytotoxic marker ~10%
- CD56+ ~10%
- T lineage markers:
- Loss of T cell markers is common and is helpful in diagnosis
- CD3+ 80-90%
- CD5+ 50-60%
- CD4+ 50%
- CD8+ 20%
- CD4/CD8 double negative ~30%
Genetic analysis
- Most cases show T cell gene rearrangement
- ~1/3 show clonal immunoglobulin gene rearrangement
- Complex cytogenetic abnormalities often present and are highly variable
- Help establish clonality but are not prognostically significant
- In situ hybridization for EBV early region RNA (EBER):
- ~60% of cases positive; EBV+ cells correspond to CD20+ B immunoblasts
