LiquidSEQ™

LiquidSEQ™ is a blood-based, comprehensive genomic profiling test, also known as a liquid biopsy, that evaluates 523 genes and delivers personalized genomic information on a wide variety of cancer-related biomarkers including clinically actionable genes and genomic signatures for patients with solid tumors. Actionability is defined as information that might aid a clinician in diagnosis, prognosis, and/or treatment strategy for a patient.¹

This precision medicine approach can help healthcare providers identify treatment strategies and can inform on clinical trial availability and eligibility based on the genomic profile of that patient’s tumor. Many FDA-approved therapies, including targeted therapies, immunotherapy, and clinical trial eligibility, rely on accurate detection and reporting of mutations in clinically relevant genes in a timely manner to improve patient outcomes.

When tissue-based, comprehensive genomic profiling is not feasible or genomic profiling requires expedited delivery based on medical justification, blood-based comprehensive genomic profiling may be considered to guide treatment decision-making by evaluating many genomic biomarkers simultaneously from a single blood draw with quicker delivery of results than tissue-based testing may provide. This is helpful in guiding a patient’s treatment for solid tumors/cancer. These genes were selected based on actionability of mutations identified in those genes, using currently available evidence from national and international guidelines and literature.

Any significant genomic findings are annotated according to Association for Molecular Pathology (AMP) reporting guidelines. A board-certified Quest clinician will review and validate the results and prepare a report for the treating physician.²

Blood-based genomic testing via liquid biopsy allows for cancer patients to benefit from treatments that target cancer cells containing specific genetic mutations. For patients who have insufficient tumor tissue for tissue-based genomic profiling or require expedited genomic information, liquid biopsy testing is an alternative method to assess eligibility for these targeted therapies and immunotherapies to help healthcare providers manage a patient.

Guidelines exist for using results from genomic testing for selection of FDA-approved therapies.^2,3 Blood-based genomic panel testing allows for diverse data generation and shorter turnaround time than solid-tumor testing, and enables enrollment in specific clinical trials and adaptation of treatment strategies as quickly as possible.^4,5,6

Clinical trial information provided in this test report is solely for informational purposes for the physician and does not constitute any endorsement or a recommendation for enrollment of patients in any trial by Quest Diagnostics, its affiliates, or its employees.

LiquidSEQ™ was developed for patients with a solid tumor, typically for advanced cancer, when prognosis or treatment selection could be informed by the presence of genomic variants and microsatellite instability/tumor mutational burden (MSI/TMB) status. Clinical situations where this panel may be helpful include the following: 

• Patients who are not eligible for invasive tissue sampling or have insufficient tissue for tissue-based genomic profiling
• Patients whose past tissue-based testing did not completely assess all recommended biomarkers or who have disease progression
• Patients with new diagnoses who may benefit from knowing the status of the most clinically significant biomarkers
• Patients with metastatic or recurrent disease that may exhibit genomic differences between the primary tumor and the metastases

LiquidSEQ™ is a 523-gene comprehensive genomic profiling test that uses next-generation sequencing to detect mutations present in circulating tumor DNA extracted from whole blood. The test is designed to detect single-nucleotide variants (SNVs), small insertion/deletions, copy number variants, and fusions, as well as evaluate microsatellite instability (MSI) and tumor mutational burden (TMB) status.

Submit 2 Streck cell-free DNA blood collection tubes containing 10 mL of blood, each shipped in the LiquidSEQ™ sample collection kit at ambient temperature. Stability is 7 days from collection to initiation of testing.

Yes. If tumor tissue is available, the Solid TumorSEQ™ test (test code 14309) will also detect clinically actionable genomic variants within the tumor tissue. No other blood-based cancer genomic profiling test is available at Quest.

Additionally, a reflex test code is available that includes LiquidSEQ™ with reflex to Solid TumorSEQ™ (test code 14343) in the event LiquidSEQ™ yields insufficient nucleic acid to perform the test or if LiquidSEQ™ yields no actionable mutations and tissue will be available to perform Solid TumorSEQ™ if negative.

Please contact the dedicated Quest customer service team at 1.833.422.0799 or DGXLEWOncologyReports@questdiagnostics.com

To discuss possible germline implications of a test result with a Quest genomic science specialist, please call Quest Genomic Client Services at 1.866.GENE.INFO (1.866.436.3463).

On average, results will be completed within 7 to 10 days after receipt of the sample in the laboratory. Results may be delayed by incomplete orders and insurance authorizations.