MDS with del(5q) cytogenetic abnormality
Deterministic view of the source YAML entity. Clinical authority remains with the cited source IDs and reviewer sign-off state.
| ID | BIO-MDS-DEL-5Q |
|---|---|
| Type | Biomarker |
| Aliases | 5q minus syndrome5q- syndromeMDS del 5qdel(5q) MDSisolated del(5q)МДС з цитогенетичною аномалією del(5q) |
| Status | reviewed 2026-04-30 | pending_clinical_signoff |
| Diseases | None declared |
| Sources | SRC-ESMO-MDS-2021 SRC-IPSS-M-BERNARD-2022 SRC-MDS-004-FENAUX-2011 SRC-NCCN-AML-2025 |
Biomarker Facts
| Biomarker type | copy_number |
|---|---|
| Mutation details | {"functional_impact": "haploinsufficiency of CSNK1A1 (CK1α) and ribosomal RPS14 — selectively lenalidomide-sensitive", "gene": "5q (commonly deleted region 5q31-q33; CDR includes RPS14, CSNK1A1, miR-145, miR-146a)", "variant_type": "interstitial deletion"} |
| Measurement | MethodConventional karyotype (G-banding) on bone marrow ± FISH (5q31/EGR1 probe) when karyotype fails or insufficient metaphases; SNP array as adjunct Unitscategorical (positive | negative); isolated vs +1 additional non-7 abnormality vs complex karyotype subclassification |
| Related biomarkers | BIO-TP53-MUTATION BIO-AML-TP53-ADVERSE |
Notes
del(5q) is detected in ~10-15% of MDS-LR cases. WHO 5th edition recognizes "MDS with isolated del(5q)" as a distinct entity defined by the 5q deletion as the sole cytogenetic abnormality (or with one additional non-monosomy-7 abnormality), <5% BM blasts, and characteristic clinical features (macrocytic anemia, normal-to-high platelets, hypolobated megakaryocytes). Lenalidomide MDS-003 (Houston phase-2) + MDS-004 (phase-3 RCT, Fenaux et al., Blood 2011) — at 10 mg PO d1-21/28d: ~56% achieve RBC transfusion independence vs 5.9% placebo at 26 weeks; ~20-25% achieve cytogenetic CR (loss of del(5q) clone). Mechanism: cereblon-mediated selective degradation of CK1α encoded within the 5q33.1 commonly-deleted region — del(5q) cells haploinsufficient and uniquely sensitive. CRITICAL: TP53 co-mutation (~20% of del(5q) MDS) predicts lenalidomide resistance + higher AML transformation risk (~30-40% at 2 years vs ~10% TP53-WT) — TP53 NGS screening mandatory before initiating lenalidomide. Triggers RF-MDS-DEL-5Q-ISOLATED (existing).
Used By
Biomarker
BIO-AML-TP53-ADVERSE- TP53-mutated AML (adverse risk)