What is “next generation sequencing” and how can I determine if we have had it done on our cancer or not

TL;DR: Next-generation sequencing (NGS) is a lab test that reads your cancer's DNA to find mutations that might respond to specific drugs—and you can find out if you had it done by checking your pathology report or asking your oncology team directly.

KEY POINTS:

• NGS is a powerful genetic test that analyzes hundreds or thousands of genes in your tumor at once, looking for mutations that guide treatment decisions
• It's different from older tests that only check one or two specific genes—NGS gives a much more complete picture of your cancer's genetic makeup
• Your pathology report should clearly state if NGS was performed; look for terms like "comprehensive genomic profiling," "tumor sequencing," or the name of a specific NGS test (like Foundation One, Guardant, or MSK-IMPACT)
• NGS results can identify targeted therapy options, immunotherapy eligibility, and sometimes clinical trials you might qualify for
• Not all cancers automatically get NGS—your doctor decides based on cancer type, stage, and whether the results would change treatment

NEXT STEP: Pull out your pathology report right now and search for the words "sequencing," "genomic," or "NGS"—or call your oncology clinic and ask directly: "Was next-generation sequencing performed on my tumor?"

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FULL ANSWER

What Is Next-Generation Sequencing (NGS)?

Next-generation sequencing is a laboratory test that reads the genetic code (DNA) of your cancer cells. Instead of checking just one or two specific genes like older tests do, NGS examines hundreds or even thousands of genes simultaneously, looking for mutations—changes in the DNA that might make your cancer vulnerable to specific treatments.

Think of it this way: Older genetic tests are like checking a few pages of a book for typos. NGS reads the entire book at once.

How NGS Works (The Basic Idea)

Your tumor sample (from a biopsy or surgery) is sent to a specialized lab. The lab:

1. Extracts the DNA from your cancer cells
2. Uses advanced technology to "read" the genetic code
3. Compares it to normal DNA to find mutations
4. Creates a detailed report of what mutations are present

These mutations can reveal:

• Targetable mutations: Specific genetic changes that respond to targeted drugs (like EGFR mutations in lung cancer or BRCA mutations in breast cancer)
• Immunotherapy markers: Whether your tumor has high microsatellite instability (MSI-H) or mismatch repair deficiency (dMMR), which can predict response to immunotherapy
• Tumor mutational burden (TMB): How many mutations your cancer has, which can guide immunotherapy decisions
• Gene amplifications or fusions: Abnormal copies of genes or genes stuck together in unusual ways

Why Doctors Order NGS

According to NCCN (National Comprehensive Cancer Network) Guidelines, NGS is increasingly recommended because it can:

• Identify treatment options you might not otherwise know about
• Find mutations that respond to FDA-approved targeted therapies
• Predict which immunotherapies might work best
• Uncover eligibility for clinical trials
• Provide prognostic information (how the cancer might behave)

How to Determine If You've Had NGS Done

Check Your Pathology Report First: Your pathology report is the official document from the lab that analyzed your tumor. Look for these terms:

• "Next-generation sequencing" or "NGS"
• "Comprehensive genomic profiling" or "CGP"
• "Tumor sequencing"
• "Molecular testing"
• Names of specific NGS tests: Foundation One, Guardant360, MSK-IMPACT, Tempus, Invitae, or others
• "Targeted panel" or "cancer gene panel"

What to Look For:

• A section titled "Molecular Testing," "Genetic Testing," or "Genomic Analysis"
• A list of genes that were tested
• A results section showing which mutations (if any) were found
• The name of the testing company or lab

If You Can't Find It in Your Report:

1. Call your oncology clinic and ask: "Was next-generation sequencing or comprehensive genomic profiling performed on my tumor?"
2. Ask specifically: "What genes were tested, and what mutations were found?"
3. Request a copy of the full pathology report and any molecular testing results if you don't have them

Important Context: Not Everyone Gets NGS

NGS isn't automatically done on every cancer. Your oncologist decides based on:

• Cancer type: Some cancers (like advanced lung cancer, melanoma, or certain breast cancers) are more likely to benefit from NGS
• Stage: Advanced cancers are more likely to get tested than early-stage cancers
• Treatment implications: Your doctor considers whether the results would actually change your treatment plan
• Insurance coverage: Some insurance plans require specific criteria before approving NGS

According to the American Cancer Society, NGS is becoming standard of care for many advanced cancers, but it's not yet universal for all cancer types.

What If You Haven't Had NGS Yet?

If your pathology report doesn't mention NGS and you have advanced cancer, it's worth asking your oncologist:

• "Would comprehensive genomic profiling be helpful for my cancer?"
• "Are there any mutations we should test for that might open up treatment options?"
• "Would my insurance cover this test?"

What Happens With NGS Results?

Once results come back, your oncologist uses them to:

• Select targeted therapies that match your specific mutations
• Determine immunotherapy eligibility
• Identify clinical trials you might qualify for
• Understand your cancer's behavior and prognosis

According to ASCO (American Society of Clinical Oncology) Guidelines, NGS results should be discussed with your care team to determine the best treatment strategy for YOUR specific situation.

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This information is for educational purposes only. Always consult your healthcare team for personalized medical advice and decisions.