BCL2 rearrangement (t(14;18) IGH/BCL2 by FISH break-apart)

Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.

ID	`BIO-BCL2-REARRANGEMENT`
Type	Biomarker
Aliases	BCL2 rearrangementBCL2 rearrangement (t(14;18) IGH/BCL2 — FISH break-apart)
Status	reviewed 2026-04-25 \| pending_clinical_signoff
Diseases	None declared
Sources	`SRC-NCCN-BCELL-2025`

Biomarker Facts

Biomarker type	gene_fusion
Mutation details	{"functional_impact": "constitutive BCL2 over-expression → apoptosis resistance", "gene": "BCL2", "variant_type": "fusion (t(14;18)(q32;q21) IGH/BCL2)"}
Measurement	MethodFISH break-apart probe on FFPE biopsy Unitscategorical (positive \| negative)
Related biomarkers	`BIO-BCL2-EXPRESSION-IHC` `BIO-DOUBLE-HIT` `BIO-MYC-REARRANGEMENT`

Notes

Defining feature of FL (~85% — t(14;18) IGH/BCL2). Component of double-hit (HGBL-DH) when co-occurring with MYC rearrangement — worse prognosis than either alone, drives DA-EPOCH-R over R-CHOP. Rare standalone in DLBCL (~20-30%). Triple-hit (with BCL6 also) rarest + worst.

Used By

Actionability

BMA-BCL2-REARRANGEMENT-DLBCL-NOS - Isolated BCL2 rearrangement in DLBCL (no MYC partner) — common in GCB-DLBCL transformed f...
BMA-BCL2-REARRANGEMENT-FL - t(14;18) IGH/BCL2 is the defining genetic lesion of follicular lymphoma (~85%). Drives co...
BMA-BCL2-REARRANGEMENT-HGBL-DH - BCL2-R as the partner of MYC-R defines HGBL-DH. Same management as MYC-R cell: DA-EPOCH-R...
BMA-BCL2-REARRANGEMENT-MCL - BCL2 rearrangement in MCL is very rare and usually denotes composite lymphoma or transfor...

Biomarker

BIO-BCL2-EXPRESSION-IHC - BCL2 expression by IHC
BIO-BCL6-REARRANGEMENT - BCL6 rearrangement (3q27) by FISH break-apart
BIO-DOUBLE-HIT - Double-hit (MYC + BCL2 and/or BCL6 rearrangements)

Indications

IND-HGBL-DH-1L-DAEPOCHR - IND-HGBL-DH-1L-DAEPOCHR
IND-HGBL-DH-1L-RCHOP - IND-HGBL-DH-1L-RCHOP

Questionnaires

QUEST-HGBL-DH-1L-STUB - High-Grade B-Cell Lymphoma, Double-Hit / Triple-Hit — first line