HER2-niedrig (Brust — IHC 1+ ODER IHC 2+ ISH-negativ)
Deterministische Ansicht der Quelle YAML Entität. Klinische Autorität bleibt mit den zitierten Quell-IDs und Rezensenten Sign-off Zustand.
| ID | BIO-HER2-LOW |
|---|---|
| Art | Biomarker |
| Aliase | ERBB2-niedrigHER2 IHC 1+HER2 IHC 2+/ISH-HER2-low (РМЗ — ІГХ 1+ АБО ІГХ 2+ ISH-)HER2-niedrige Brust |
| Status | reviewed 2026-04-29 | pending_clinical_signoff |
| Erkrankungen | DIS-BREAST |
| Quellen | SRC-DESTINY-BREAST04-MODI-2022 SRC-ESMO-BREAST-METASTATIC-2024 SRC-NCCN-BREAST-2025 |
Biomarker-Fakten
| Biomarker-Typ | protein_expression_ihc |
|---|---|
| Messung | VerfahrenIHC (4B5 / HercepTest); Reflex ISH (FISH/ZISCH/SISCH) für IHC 2+. Brustscoring verwendet 2018 ASCO/CAP Kriterien — Umfangsmembrane Färbung ≥ 10%. EinheitenIHC 0 | 1+ | 2+ (ISH-non-amplified) — HER2-low = IHC 1+ OR (IHC 2+ AND ISH HER2/CEP17 ratio <2.0 AND HER2 signals/cell <4.0) |
| Verwandte Biomarker | BIO-HER2-SOLID BIO-ESTROGEN-RECEPTOR |
Anmerkungen
HER2-low (IHC 1+ OR IHC 2+/ISH-) covers ~50-55% of HER2-non-positive breast cancers. DESTINY-Breast04 (Modi 2022) established T-DXd efficacy 2L+ in HER2-low metastatic breast (HR+ post-endocrine + ≥1 prior chemo, OR TNBC post-≥1 prior chemo): mPFS 9.9 vs 5.1 mo, OS 23.4 vs 16.8 mo. DESTINY-Breast06 extended signal to HER2-ultralow (IHC ≥0 with membrane staining) post-endocrine in HR+. Pathology challenge: IHC 1+ vs 0 has poor inter-observer reproducibility — ASCO/CAP 2023 update ongoing. ILD class warning (~12% any-grade, 1-2% G≥3) is dominant safety concern. Distinct from BIO-HER2-SOLID (which is named/scoped for gastric/GEJ/CRC scoring conventions).
Verwendet von
Therapeutische Relevanz
BMA-HER2-LOW-BREAST- Trastuzumab Deruxtecan (T-DXd, DS-8201) ist FDA-genehmigt (Aug 2022) für unresectable oder mich...
Biomarker
BIO-HER2-ULTRALOW- HER2-ultralow (Brust — IHC > 0 < 1+; schwache/unvollständige Membranfärbung ≤ 10 %)
Kapitel des Handbuchs
HB-BREAST-HR-POS-HER2-NEG-1L- HR+/HER2- metastasierter Brustkrebs:
Handbuchfragen
HQ-BREAST-HR-POS-1L-003- HQ-BREAST-HR-POS-1L-003
Anwendungsgebiet
IND-BREAST-HER2-LOW-2L-DATO-DXD- IND-BREAST-HER2-LOW-2L-DATO-DXD