BCL2 expression by IHC
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BIO-BCL2-EXPRESSION-IHC |
|---|---|
| Type | Biomarker |
| Aliases | B-cell lymphoma 2BCL2BCL2 expression by immunohistochemistryЕкспресія BCL2 (імуногістохімія) |
| Status | reviewed 2026-04-25 | pending_clinical_signoff |
| Diseases | None declared |
| Sources | SRC-NCCN-BCELL-2025 |
Biomarker Facts
| Biomarker type | protein_expression_ihc |
|---|---|
| Measurement | MethodIHC on FFPE biopsy (anti-BCL2 antibody, 124 clone) Unitscategorical (positive ≥50% | negative); semi-quantitative percentage often reported |
| Related biomarkers | BIO-BCL2-REARRANGEMENT BIO-DOUBLE-HIT |
Notes
Cross-disease relevance: - **CLL/SLL**: BCL2-dependent — venetoclax (BCL-2 inhibitor) is highly active. Universal CLL marker; drives VenO 1L choice for high-risk. - **MCL**: cyclin-D1+ MCL is also BCL2+; predicts venetoclax-rituximab sensitivity in r/r — emerging 2L+ pathway. - **FL**: defining via t(14;18) IGH/BCL2 (~85%) — over-expression blocks apoptosis. Tazemetostat (EZH2 inhibitor) emerging in EZH2-mut r/r FL. - **DLBCL**: double-expressor (BCL2+ ≥50% IHC + MYC+ ≥40% IHC at protein level, distinct from FISH double-hit) is adverse but does NOT change 1L regimen per current evidence. - **HGBL-DH**: BCL2 rearrangement is part of double-hit definition (with MYC + optionally BCL6). - **MM**: t(11;14) MM subset highly venetoclax-sensitive; emerging therapy. Direct algorithm-driving currently: indirectly via BIO-DOUBLE-HIT in HGBL-DH + via venetoclax-eligible flag in CLL high-risk. Future: drive r/r 2L+ venetoclax pathway across all BCL2-dependent diseases.
Used By
Actionability
BMA-BCL2-EXPRESSION-AML- Venetoclax (BCL2 inhibitor) + azacitidine or decitabine is FDA-approved (Oct 2020) for ne...BMA-BCL2-EXPRESSION-CLL- CLL universally expresses BCL2 (no rearrangement needed; driven by miR-15/16 deletion at...BMA-BCL2-EXPRESSION-DLBCL-NOS- High BCL2 IHC expression in DLBCL — common in GCB and ABC subsets. 'Dual-expressor' (BCL2...BMA-BCL2-EXPRESSION-FL- High BCL2 expression universal in FL (driven by t(14;18)). Diagnostic but not therapy-sel...BMA-BCL2-EXPRESSION-MCL- High BCL2 in MCL universal (cyclin D1-driven survival pathway). Venetoclax + ibrutinib (A...
Biomarker
BIO-BCL2-IHC- BCL2 expression by IHCBIO-BCL2-REARRANGEMENT- BCL2 rearrangement (t(14;18) IGH/BCL2 by FISH break-apart)
Indications
IND-DLBCL-1L-POLA-R-CHP- IND-DLBCL-1L-POLA-R-CHPIND-DLBCL-1L-RCHOP- IND-DLBCL-1L-RCHOP
Questionnaires
QUEST-DLBCL-NOS-1L-STUB- Diffuse Large B-Cell Lymphoma, Not Otherwise Specified — first line