Biomarkers for Systemic Therapy in Metastatic Breast Cancer
Key Points
Key Points
- Testing for PIK3CA and estrogen receptor 1 gene (ESR1) somatic variants and germline BReast CAncer gene 1 (BRCA1), BReast CAncer gene 2 (BRCA2), and partner and localizer of BRCA2 (PALB2) pathogenic variants (mutations) to guide therapy.
- Testing tumors for homologous recombination deficiency, expression of programmed cell death ligand-1 (PD-L1), deficient mismatch repair microsatellite instability (dMMR/MSI), tumor mutational burden (TMB), neurotrophic tyrosine receptor kinase (NTRK) gene fusions, and trophoblast cell-surface antigen 2 (TROP2) expression to determine eligibility for selected treatments.
- The use of cell-free, circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) for monitoring treatment response.
Diagnosis
...agnosis...
...mendations from 2023 Rapid Recommendation Updat...
...id in treatment selection, the Expert Panel recomm...
...viously treated with ET and a CDK4/6 inhib...
...Recommendations from 2022 Focused Gui...
...n 1.1Patients with locally recurrent...
...mendation 2.1There are insufficient data at pres...
...tion 3.1Patients with metastatic HER2-negativ...
...mendation 3.2There is insufficient evidence to sup...
...tion 4.1There are insufficient data at...
...endation 5.1Patients with locally recurrent...
...commendation 6.1Patients with metast...
...commendation 7.1Patients with metastatic...
...ndation 8.1Clinicians may test for NTR...
...commendation 9.1There are insufficient d...
...tion 10.1There are insufficient data t...
...ommendation 11.1There are insufficient da...
...Unchanged From 2015 Guideline...
...entation of metastasis from breast c...
...mendation for Tissue Biomarkers
...ts who are already receiving systemic...
...tions for Circulating Tumor Markers...
...nts already receiving systemic thera...
...c antigen (CEA), cancer antigen (CA)...
...t-A-Glance Guide to ASCO Biomarker Testing in M...
...rker Tests Recommended by the ASCO Exper...
...omarker Tests Not Recommended by the AS...
...CO believes that cancer clinical trials are vital...