Guardant360 Liquid Biopsy Test

Guardant360 is a blood-based comprehensive genomic profiling (liquid biopsy) test made by Guardant Health that analyzes circulating tumor DNA (ctDNA) in advanced solid tumor cancers. It looks for actionable mutations, resistance markers, and select biomarkers that can help guide targeted therapy and immunotherapy decisions without a new tissue biopsy.

Guardant360 (the original, expanded-panel version) is a CLIA-validated laboratory-developed test (LDT) and is not itself FDA-approved. Guardant360 CDx is a separate, FDA-approved 55-gene assay approved as a companion diagnostic for specific therapies. Guardant360 Liquid CDx is Guardant Health's newer, FDA-approved liquid biopsy panel with a substantially larger genomic and epigenomic footprint that has taken over the companion diagnostic indications previously assigned to Guardant360 CDx. BigOHealth can help you understand which version your report is from and what that means for your treatment options.

It depends which version. The original expanded-panel Guardant360 is an LDT and is not FDA-approved. Guardant360 CDx and the newer Guardant360 Liquid CDx are FDA-approved as companion diagnostics for select indications, including certain non-small cell lung cancer, colorectal cancer (BRAF V600E), and ESR1-mutant breast cancer therapy decisions. Your report header usually states which assay was run — we can confirm this for you during report review.

Guardant360 test cost in India depends on the specific assay version, logistics, and whether report interpretation is included. Contact BigOHealth for current Guardant360 test pricing and for pricing on reviewing a Guardant360 report you already have.

Guardant360 panels cover a broad set of cancer-related genes commonly including EGFR, KRAS, ALK, BRAF, MET, RET, ROS1, ERBB2/HER2, PIK3CA, ESR1, BRCA1/2, and others, along with copy number changes and select fusions depending on the exact assay version. The precise gene list, reportable alteration types, and any biomarkers (such as blood TMB) vary between the LDT, Guardant360 CDx, and Guardant360 Liquid CDx versions — we walk you through exactly what your specific report includes.

Guardant360 TissueNext is Guardant Health's tissue-based comprehensive genomic profiling test, offered alongside the blood-based Guardant360 liquid biopsy. Some patients are tested with both, or reflexed to tissue when a liquid biopsy result is negative or inconclusive due to low ctDNA shedding.

Both are liquid biopsy platforms used in advanced solid tumors, but they differ in panel size, reportable biomarkers, and companion diagnostic claims for specific drugs. Neither is universally "better" — the right choice depends on your cancer type, the therapy decision your oncologist is trying to make, and which companion diagnostic claims apply. We can help you or your oncologist compare the two for your specific situation.

Guardant Reveal and Guardant360 are different Guardant Health tests built for different purposes. Guardant360 is a comprehensive genomic profiling test used mainly in advanced/metastatic cancer to find actionable mutations for treatment selection. Guardant Reveal is designed for minimal residual disease (MRD) detection after curative-intent treatment, mainly in colorectal cancer, to help assess recurrence risk. They are not interchangeable, and confusing the two can lead to the wrong test being ordered.

No. Guardant360 is a somatic (tumor-derived) genomic profiling test, not a hereditary/germline genetic test. It looks at mutations picked up from the tumor via blood, not inherited mutations passed through families. If hereditary cancer risk is a concern, a separate germline panel such as a hereditary cancer panel or BRCA1/BRCA2 test is needed.

Yes. If you already have a Guardant360, Guardant360 CDx, or Guardant360 Liquid CDx report, our molecular oncology team can review it independently and explain the actionable mutations, resistance findings, VUS, and next-step options — without requiring you to repeat the test unless clinically necessary.

A Guardant360 report typically separates findings into clinically actionable alterations matched to therapies or trials, alterations of unclear significance (VUS), and a summary of assay performance such as ctDNA fraction or sample adequacy. Reading it correctly means matching each finding to your specific cancer type and treatment history — which is why we recommend an expert walkthrough rather than interpreting the PDF alone.

Guardant360 results are typically available within 7–14 business days of sample collection and lab receipt, though turnaround can vary by assay version, logistics, and sample quality.

Guardant360 Response is a separate Guardant Health test built to track ctDNA levels across serial blood draws during treatment, to help assess whether a patient is responding to therapy — it is not the same as baseline Guardant360 mutation profiling. Guardant360 (and its CDx/Liquid CDx versions) is used to find actionable mutations before or at the start of treatment; Guardant360 Response is used afterward, to monitor how ctDNA changes over time on therapy.

A tumor response map is a way of visualizing how ctDNA levels (such as variant allele fraction) change across serial Guardant360 Response draws during treatment — a falling trend generally supports treatment response, while a rising trend may prompt an earlier look at imaging or a treatment change. This is a monitoring report, distinct from your baseline Guardant360 mutation profiling report, and should be interpreted alongside imaging and clinical status, not on its own.