Chapter 7: The Evidence

Chapter 7: The Evidence

How Genomic Testing Can Improve Cancer Care

When you’re making decisions about your cancer treatment, it’s natural to wonder:

• "Does genomic testing really make a difference?"
• "Will it help me get better treatment?"
• "Is it worth doing?"

These are important questions—and the good news is, we now have strong scientific evidence from thousands of patients showing how genomic testing can meaningfully improve outcomes, expand treatment options, and help doctors make more confident decisions.

In this chapter, we will walk you through some of the most important findings, explained in simple language so you can understand what they mean for you.

1. Genomic Testing Helps Doctors Choose the Right Treatment Earlier

Across multiple studies, patients who received a comprehensive genomic test were more likely to get a treatment matched to the biology of their cancer.

• Key Finding: 30–65% of patients get a treatment change or upgrade after genomic testing.

What does this mean for you?

• Your doctor may discover treatment options that were not visible before.
• You may avoid treatments that won’t work.
• You get to the right therapy earlier, without trial and error.

Example:

In one study of lung cancer patients, genomic testing influenced treatment decisions in ~50% of cases. (Reference: Singal et al., Rozenblum et al.)

2. Patients Who Receive Matched Therapies Often Do Better

Targeted therapies are designed to attack specific mutations. When patients receive matched therapy based on genomic test results, they frequently experience:

• Longer time before the cancer grows
• Better overall response
• Higher chances of disease stability

Examples from research:

• Study of 429 patients: Patients receiving matched therapy had significantly longer progression-free survival compared to those who didn’t. They also had a higher rate of stable disease or partial/complete remission. (Reference: Kato et al.)
• Study of 149 metastatic cancer patients: Matched therapy led to longer survival and lower risk of disease progression. (Reference: Sicklick et al.)

3. Genomic Testing Helps Identify Immunotherapy Candidates

Immunotherapy can be life-changing for certain patients—but only if their tumor has the right features. Genomic tests identify biomarkers like:

• TMB (Tumor Mutational Burden)
• MSI (Microsatellite Instability)
• PD-L1

Key Insight: Many patients who benefit from immunotherapy would not have been identified without genomic testing. This is especially important for cancers where immunotherapy is effective only in small subgroups.

4. Genomic Testing Helps Patients Access Clinical Trials

Many patients worry that they’ve “run out of options.” Genomic testing opens doors.

• Key Finding: 11% of patients in a study of 10,000 were found eligible for clinical trials purely because of genomic test results. (Reference: Prospective CGP study, 10,000 patients)

This is crucial because clinical trials can offer:

• New, promising therapies
• Earlier access to drugs not yet widely available
• Better-tailored treatments based on your mutation

5. Even When No Actionable Mutation Is Found, It Still Helps

This surprises many patients—but “no finding” is also meaningful information.

• In colon cancer: if your tumor is KRAS wildtype (meaning no KRAS mutation), you become eligible for anti-EGFR targeted therapies.
• Saving time: Genomic testing can confirm that certain drugs won’t work, saving you time and side effects.
• Comprehensive view: It allows doctors to look beyond small panels and consider more comprehensive genomic profiling (100s to 20,000 genes), ensuring nothing important is missed.
• Next steps: It may guide your doctor to immunotherapy markers, germline findings, or eligibility for advanced sequencing.

6. Real-World Impact: What These Numbers Mean for You

Let’s put everything together. With genomic testing, you may:

• Get the right treatment earlier
• Avoid medicines that won’t help
• Access targeted therapies matched to your genes
• Understand whether immunotherapy may work
• Receive more personalized care
• Become eligible for new clinical trials
• Gain clarity and confidence in your treatment plan

In short: Genomic testing turns uncertainty into information—and information into better decisions.

7. The Bottom Line: Genomic Testing Isn’t Just Science. It’s Personal.

These statistics aren’t just numbers from research papers. They represent thousands of real patients—mothers, fathers, grandparents, and young adults—whose treatments improved because their doctors understood the genetic story of their cancer.

Genomic testing helps your doctor look beyond the surface and choose the treatment that fits your cancer best. Because your cancer is unique—and your treatment should be too.

Suggested References

1. Singal G. et al. Study of ~1700 patients with advanced NSCLC: molecularly matched therapy improved OS.
2. Rozenblum A.B. et al. Genomic testing influenced treatment decisions in ~50% of lung cancer cases.
3. Kato S. et al. Analysis of 429 cancer patients: matched therapy improved PFS and disease control.
4. Sicklick J.K. et al. Study of 149 metastatic cancer patients: improved outcomes with matched therapy.
5. Prospective CGP study (10,000 patients): 11% eligible for clinical trials based on genomic test results.
6. Multiple studies on TMB/MSI/PD-L1 guiding immunotherapy decisions.