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 Content is derived from published guidelines and regulatory sources and may contain errors or outdated information.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 →
Stage Stage IVA
Single extrathoracic metastatic lesion or contralateral lung nodule or pleural/pericardial involvement. Metastatic but potentially oligometastatic.
5 test recommendations across 1 clinical indication
Stage IVA metastatic TNBC. Comprehensive molecular panel required for pembrolizumab, PARP inhibitor, NTRK, and TMB-directed therapy eligibility.
Required — 4 tests
PD-L1 Expression by Immunohistochemistry (IHC)
PD-L1 IHC
Measurement of PD-L1 (programmed death-ligand 1; CD274) protein expression on tumor cells by IHC. Reported as Tumor Proportion Score (TPS) for NSCLC. Key thresholds: TPS <1% (PD-L1 negative), TPS 1–49% (low expression), TPS ≥50% (high expression). FDA-approved companion diagnostics: 22C3 pharmDx (pembrolizumab), 28-8 pharmDx (nivolumab), SP142 (atezolizumab), SP263 (durvalumab). PD-L1 ≥50% qualifies for pembrolizumab monotherapy first-line; all TPS levels are relevant for combination chemo-immunotherapy selection.
Ordering Note
PD-L1 CPS ≥10 for pembrolizumab (Keytruda) + chemotherapy eligibility in metastatic TNBC (KEYNOTE-355).
Specimen
Evidence
BRCA1/BRCA2 Germline Testing
BRCA1/2 Germline
Full sequence analysis and large rearrangement detection of BRCA1 and BRCA2 germline DNA in peripheral blood. Germline BRCA1/2 pathogenic variants found in ~5–7% of unselected breast cancer; up to 15–20% in TNBC. Eligibility criterion for PARP inhibitor therapy: olaparib (Lynparza, OLYMPIAD trial, FDA-approved 2018) and talazoparib (Talzenna, EMBRACA trial, FDA-approved 2018) for HER2− metastatic breast cancer. Also establishes hereditary risk for first-degree relatives. NCCN recommends germline testing for all metastatic breast cancer patients.
Specimen
Evidence
NTRK1/2/3 Gene Fusion Analysis
NTRK fusion
Pan-tumor detection of NTRK1, NTRK2, and NTRK3 gene fusions encoding TRK (tropomyosin receptor kinase) fusion proteins. Larotrectinib (Vitrakvi) and entrectinib (Rozlytrek) are FDA-approved pan-tumor for TRK fusion-positive cancers regardless of histology. NTRK fusions are rare in NSCLC (<1%) but the high response rate and pan-tumor approval make routine testing appropriate for all NSCLC patients. IHC screening may precede confirmatory molecular testing.
Ordering Note
NTRK fusions occur in <1% of TNBC but are highly actionable (larotrectinib, entrectinib). Required per NCCN.
Specimen
Comprehensive Solid Tumor NGS Panel
Comprehensive NGS
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
Recommended — 1 test
Tumor Mutational Burden (TMB)
TMB
Quantitative measurement of the number of somatic mutations per megabase (mut/Mb) of tumor genome. High TMB (TMB-H, ≥10 mut/Mb per FoundationOne CDx) is an FDA-approved pan-tumor biomarker for pembrolizumab (Keytruda). In NSCLC, TMB-H correlates with improved response to immune checkpoint inhibitors independently of PD-L1 expression. TMB is typically calculated from comprehensive NGS panels (FoundationOne CDx FDA-approved for TMB). Note: TMB thresholds and clinical utility vary by assay platform — direct comparison between assays requires caution.
Ordering Note
TMB ≥10 mut/Mb for pembrolizumab eligibility (tumor-agnostic FDA approval). Secondary biomarker in TNBC.
Specimen
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.
| Test | Medicare (CMS) | UnitedHealth | Anthem BCBS | Humana | Cigna | Aetna |
|---|---|---|---|---|---|---|
| PD-L1 IHC | Covered | Covered | Covered | Covered | Covered | Covered |
| BRCA1/2 Germline | Covered | Covered | Covered | Covered | Covered | Covered |
| NTRK fusion | Covered | Unknown | Unknown | Unknown | Unknown | Unknown |
| Comprehensive NGS | Covered | Covered | Covered | Prior Auth | Covered | Covered |
| TMB | Covered | Prior Auth | Covered | Prior Auth | Covered | Covered |
Coverage data last verified via automated policy research. Always confirm current policies with each payer.
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.