ALCL-HL | HL | |
---|---|---|
*The intensity of immunostaining may vary within the same case; †results can vary depending on the fixative used; ‡membrane bound and/or dot-like positivity; §some cases with morphology and phenotypic profile consistent with ALCL-HL (including BSAP negativity) can lack t(2;5)/ALK protein expression: these cases need further studies to assess their definitive inclusion among anaplastic large cell lymphomas; ¶in 1–2% of the cases T cell receptor gene rearrangement occurs. | ||
EBV, Epstein-Barr virus; EMA, epithelial membrane antigen; TCR, T cell receptor. | ||
Morphological characteristics | ||
Neoplastic component | Usually cohesive | Usually dispersed |
Reactive component | Often minor | Usually prevalent |
Reed-Sternberg cells | May be present | Always present |
Intrasinusoidal diffusion | Typical | Exceptional |
Molecular characteristics | ||
CD30 | + | +* |
CD45 | +/− | − |
CD15 | −/+ | +/− |
EMA | +/− | rare |
CBF.78 | + (80–90%) | −/+ (rare cells) |
BHN.9 | + (60%)† | − (5%) |
CD3 | −/+‡ | 10% |
T cell rosettes | − | +/− |
p53 | −/+ | + |
EBV | −/+ | + or +/− |
Clonal TCR gene rearrangement | + | ¶ |
Clonal Ig gene rearrangement | − | + |
PAX-5 gene product/BSAP | − | + |
t(2;5)/ALK protein | +§ | − |