Introduction
Name | Status | Assessment | ESCAT tier | Function | Relevance for BC subtype | Reference |
---|---|---|---|---|---|---|
Estrogen receptor (ER) | Expression, mutation | IHC, sequencing | I‑A | Prognostic and predictive, classification of BC | HR+ BC (Luminal A/B) | [5] |
Progesterone receptor (PR) | Expression, mutation | IHC, sequencing | I‑A | Prognostic and predictive, classification of BC | HR+ BC (Luminal A/B) | [4] |
Human epidermal growth factor receptor 2 (HER2) | Overexpression, gene amplification, mutation | IHC, in situ hybridization, sequencing | I‑A, (HER2 low: II-B) | Prognostic and predictive, classification of BC | HER2+ BC (Luminal B) | |
Programmed cell death ligand 1 (PD-L1) | Expression (IC, CPS) | IHC, sequencing | I‑A | Prognostic and predictive | TNBC | [13] |
Tumor-infiltrating lymphocytes (TIL) | Expression | IHC | NA | Prognostic and predictive | All BC subtypes | [17] |
Molecular Intrinsic subtype | Multi gene expression (recurrence risk, chemotherapy benefit (assay dependent)) | Gene expression profiling | NA | Prognostic and predictive | All BC subtypes | [18] |
Germline BRCA1/2 (somatic BRCA1/2) | Mutation | Sequencing | I‑A (II-A) | Prognostic and predictive | HR+ BC, TNBC | |
PALB2 | Mutation | Sequencing | II‑A | Prognostic and predictive | HR+ BC, TNBC | [21] |
Phosphatidylinositol 3‑kinase (PI3K) catalytic subunit (PIK3CA) | Mutation | Sequencing | I‑A | Prognostic and predictive | HR+/HER2− BC | [24] |
Microsatellite instability (MSI) | MSI-high/low | Sequencing | I‑C | Predictive | HR+, HER2+, TNBC | [25] |
Tumor mutational burden (TMB) | TMB-high/low | Sequencing | I‑C | Predictive | HR+, HER2+, TNBC | [25] |
Neurotrophic tyrosine receptor kinase (NTRK) | Fusion | IHC, in situ hybridization, sequencing | I‑C | Predictive | HR+, HER2+, TNBC | [27] |
Circulating tumor DNA (ctDNA) | Expression | Isolation from liquid biopsies | NA | Predictive and prognostic | All BC subtypes | [28] |
Homologous recombination deficiency (HRD) | HRD-high/low | Sequencing | NA | Predictive and prognostic | All BC subtypes | [22] |