genoCDS

Medical Disclaimer

genoCDS is a clinical reference tool for qualified healthcare professionals only. Content is derived from published guidelines and regulatory sources and may contain errors or outdated information. It is not a substitute for professional medical judgment, institutional protocols, or individual patient assessment. Always verify recommendations against current primary sources before making clinical decisions. Full disclaimer →

Breast Cancer · HER2+ Breast Cancer

Stage Stage I

Tumor ≤4 cm, no nodal or distant metastasis (T1-T2a, N0, M0). Surgically resectable.

2 test recommendations across 1 clinical indication

At Diagnosis

Stage I HER2+ — HER2 IHC/FISH required to confirm HER2 status and guide targeted therapy.

Required 1 test

RequiredFDA Companion Dx

HER2 Testing (IHC + FISH)

HER2 IHC/FISH

LOINC 85319-2

HER2 (ERBB2) status testing by immunohistochemistry (IHC) with reflex to FISH for IHC 2+ equivocal results, per ASCO/CAP 2018 guidelines. IHC 3+ = HER2 positive. FISH amplification ratio ≥2.0 or average HER2 copy number ≥6.0 signals/cell = HER2 positive. IHC 1+ and 2+/FISH non-amplified = HER2 low (eligible for T-DXd). Required for all newly diagnosed invasive breast cancer. FDA-approved companion diagnostic for multiple HER2-targeted therapies.

Ordering Note

HER2 status confirmation required. Companion diagnostic for trastuzumab-based regimens.

Specimen

FFPE primary tumor tissueFFPE metastatic site

Optional 1 test

OptionalFDA Companion Dx

Comprehensive Solid Tumor NGS Panel

Comprehensive NGS

LOINC 81445-4

Next-generation sequencing panel covering ≥300 cancer-relevant genes, including all major NSCLC drivers (EGFR, ALK, ROS1, BRAF, KRAS, MET, RET, NTRK, HER2, FGFR), plus tumor mutational burden (TMB) and microsatellite instability (MSI). Examples include FoundationOne CDx, Tempus xT, Caris MI Transcriptome, and equivalent institutional panels. Preferred over single-gene sequential testing for efficiency and cost-effectiveness.

Specimen

FFPE tumor tissue (≥20% tumor)Liquid biopsy (ctDNA)Fresh/frozen tumor tissue

Payer Coverage

Payer Coverage Summary

Coverage status as of last policy review. Prior authorization requirements and coverage criteria may change. Verify directly with each payer before ordering.

TestMedicare (CMS)UnitedHealthAnthem BCBSHumanaCignaAetna
HER2 IHC/FISHCoveredCoveredCoveredUnknownUnknownUnknown
Comprehensive NGSCoveredCoveredCoveredPrior AuthCoveredCovered

Coverage data last verified via automated policy research. Always confirm current policies with each payer.

Reference only. Testing guidance shown is derived from published clinical guidelines and regulatory sources. It does not constitute a clinical recommendation for any individual patient. Payer coverage information is a general summary and may not reflect current policy or individual benefit design. Full disclaimer

Recommendations on this page are derived from publicly available guidelines (NCCN, ASCO, ESMO, FDA, OncoKB) and are paraphrased for reference. They do not constitute medical advice. Evidence levels reflect the grading systems of each respective organization and should be interpreted in clinical context. This reference is updated periodically but may not reflect the most recent guideline revisions.

HER2+ Breast Cancer — Stage I | Breast Cancer | genoCDS | genoCDS