Signatera vs. Prosigna Test: Key Differences, Accuracy, and Which One You Need (2026)

Navigating precision oncology options can be complex. While both Signatera and Prosigna are advanced genomic tests used in cancer care, they serve fundamentally different clinical purposes. Here is an evidence-based breakdown of how they compare.

 

Quick Summary: Key Takeaways

• Signatera (Natera): A personalized liquid biopsy (blood test) that tracks circulating tumor DNA (ctDNA) to detect Minimal Residual Disease (MRD) and early recurrence across multiple solid tumor types (breast, colorectal, lung, bladder, etc.).
• Prosigna (Veracyte / NanoString): A standardized tissue-based gene assay (PAM50) that evaluates tumor tissue from early-stage breast cancer to determine subtype and predict 10-year risk of distant recurrence.
• Bottom Line: Prosigna helps guide initial post-surgery treatment decisions (e.g., chemotherapy necessity) in early breast cancer, whereas Signatera monitors long-term recurrence risk over time via simple blood draws.

Signatera vs. Prosigna: Direct Comparison Table

Feature	Signatera Test	Prosigna Test
Developer / Company	Natera	Veracyte (formerly NanoString)
Sample Required	Blood draw (Liquid Biopsy) + Initial Tissue Baseline	Surgical Tumor Tissue (FFPE Block)
Primary Purpose	Detect ctDNA / Minimal Residual Disease (MRD)	Gene expression profiling (PAM50) & Recurrence Risk (ROR)
Cancer Indications	Multi-cancer (Breast, Colorectal, Lung, Bladder, Melanoma, etc.)	Early-stage Breast Cancer (HR+, HER2-, postmenopausal)
Testing Frequency	Longitudinal (Repeated every few months)	One-time assay post-surgery
Key Output / Metric	ctDNA Status: Positive or Negative (with MTM/mL quantification)	ROR Score (0–100) & PAM50 Subtype (Luminal A/B, HER2, Basal)
Main Clinical Goal	Detect relapse months before imaging & monitor treatment response	Decide on chemotherapy benefit and long-term endocrine therapy

What is the Signatera Test?

Signatera is a custom-built, tumor-informed liquid biopsy developed by Natera. Unlike broad-panel genetic screening tests, Signatera is personalized to each patient’s unique tumor profile.

 

How Signatera Works:

1. Tumor Sequencing: Whole Exome Sequencing (WES) is performed on the patient’s primary tumor tissue sample alongside a blood sample.
2. Custom Panel Creation: Natera identifies 16 unique clonal mutations specific exclusively to that patient's cancer.
3. Longitudinal Monitoring: Subsequent routine blood draws search for these 16 target mutations in circulating tumor DNA (ctDNA).

Because Signatera tracks real-time molecular evidence of cancer remaining in the body (Minimal Residual Disease), a positive Signatera result indicates a high probability of cancer recurrence—often detecting it 8 to 10 months ahead of standard CT or PET scans.

What is the Prosigna Test?

The Prosigna Breast Cancer Prognostic Gene Signature Indicator (based on the PAM50 gene expression signature) is an FDA-cleared in vitro diagnostic assay. It is specifically designed for postmenopausal women diagnosed with hormone receptor-positive (HR+), HER2-negative early-stage breast cancer.

How Prosigna Works:

1. Gene Analysis: Using NanoString’s nCounter technology, the test measures the expression level of 50 key genes in surgical tumor tissue.
2. Intrinsic Subtyping: It classifies the tumor into one of four intrinsic biological subtypes: Luminal A, Luminal B, HER2-enriched, or Basal-like.
3. Risk of Recurrence (ROR) Calculation: Combines gene expression with clinical variables (tumor size and node status) to generate an ROR score from 0 to 100.

The ROR score categorizes patients into Low, Intermediate, or High risk of distant recurrence over 10 years, helping oncologists determine whether a patient can safely skip chemotherapy and rely solely on endocrine (hormone) therapy.

5 Major Differences: Signatera vs. Prosigna

1. Liquid Biopsy vs. Solid Tissue Biopsy

Prosigna is performed strictly on tumor tissue removed during surgery or biopsy. Once completed, the tissue assay is finished. Signatera, after its initial tissue baseline, relies on repeated blood draws taken every 3 to 6 months to monitor dynamic changes in your body over time.

2. Prognostic Risk Assessment vs. Molecular Disease Detection

Prosigna provides a statistical probability (risk score) of distant recurrence based on biological properties. Signatera provides a direct detection of whether fragments of tumor DNA are actively circulating in your bloodstream.

3. Cancer Type Breadth

Prosigna is exclusively tailored for early-stage breast cancer (HR+/HER2-). Signatera is tumor-informed and tumor-agnostic in application—meaning it can be custom-made for breast, colon, bladder, lung, ovarian, and multiple other solid cancers.

4. Timing of Testing

Prosigna is conducted once, shortly after surgical resection, to guide baseline treatment planning (adjuvant chemotherapy). Signatera is conducted surveillance-style over years to monitor for recurrence or to check if immunotherapy/chemotherapy is working effectively.

5. FDA Clearance & Testing Infrastructure

Prosigna received 510(k) FDA clearance and can be run locally in qualified Pathology laboratories equipped with NanoString systems. Signatera is a Laboratory Developed Test (LDT) processed centrally in Natera’s CLIA-certified, CAP-accredited central laboratory.

Can Signatera and Prosigna Be Used Together?

Yes, in breast cancer care, they are complementary rather than competing. A patient with early-stage breast cancer might first receive a Prosigna test on her surgical tumor tissue to determine if adjuvant chemotherapy is necessary. Following primary therapy, her oncologist might order Signatera blood tests every few months during surveillance to ensure no ctDNA returns.

Frequently Asked Questions (FAQs)

Q: Is Signatera better than Prosigna?

Neither test is "better"—they serve completely different functions. Prosigna predicts initial chemotherapy benefit in breast cancer tissue, while Signatera monitors blood over time for physical recurrence across multiple tumor types.

Q: How sensitive is Signatera for detecting recurrence?

Signatera has demonstrated ultra-high sensitivity and a high positive predictive value (>98%), detecting ctDNA months before traditional imaging modalities (CT, MRI, PET) show visible structural recurrence.

Q: How does Prosigna differ from Oncotype DX or MammaPrint?

Prosigna, Oncotype DX, and MammaPrint are all tissue-based gene expression tools for early breast cancer. Prosigna uses the PAM50 signature to report intrinsic biological subtypes (Luminal A/B, HER2, Basal) alongside an ROR score, providing precise 10-year distant recurrence risk assessment.

Q: Are Signatera and Prosigna covered by Medicare and insurance?

Yes, both tests generally have Medicare coverage under specific criteria. Signatera is covered under NCD/LCD guidelines for multiple solid tumors (including stage II-III colorectal, muscle-invasive bladder, and breast cancer). Prosigna is widely covered for postmenopausal women with Stage I/II HR+/HER2- node-negative or node-positive (1-3 nodes) breast cancer.

Conclusion: Summary for Patients & Clinicians

When deciding between precision medicine diagnostics, understanding the clinical objective is paramount:

• Choose Prosigna if you need a static, baseline gene expression profile to assess long-term risk and chemotherapy necessity in early HR+/HER2- breast cancer.
• Choose Signatera if you require dynamic, long-term post-treatment surveillance to detect molecular residual disease via simple blood draws across various solid cancers.

Disclaimer: This article is for informational and educational purposes only and does not constitute medical advice. Consult with a board-certified oncologist to discuss which diagnostic testing strategy is appropriate for your specific clinical scenario.