Disparities in Biomarker Testing for Stage IV Non-small Cell Lung Cancer Impact Survival
New research highlights meaningful disparities in biomarker testing rates for patients newly diagnosed with stage IV non-squamous non-small cell lung cancer (NSCLC), and demonstrates a strong correlation between lack of testing and poorer overall survival.this study, conducted in California and presented at the 2025 World Conference on Lung Cancer, underscores a critical need for systemic changes within oncology practices to ensure equitable access to precision medicine for all eligible patients.
The Critical Role of Biomarker testing in NSCLC
Biomarker testing – identifying specific genetic mutations within a patient’s tumor – is now fundamental to guiding treatment decisions in NSCLC. Identifying actionable mutations allows oncologists to utilize targeted therapies, offering potentially significant improvements in patient outcomes. Though, this study reveals that not all patients are benefiting equally from these advancements.
Key Findings: Who is Missing Out?
Researchers analyzed a large, population-based cohort of patients with newly diagnosed stage IV non-squamous NSCLC who were fit enough to receive first-line therapy.The analysis revealed stark differences in biomarker testing rates based on several demographic and socioeconomic factors:
Lower Testing Rates: Older adults, male patients, and individuals from lower socioeconomic status neighborhoods were significantly less likely to undergo biomarker testing.
Higher Testing Rates: Female patients, younger individuals, and those identifying as Asian were more likely to be tested – a finding likely linked to the higher prevalence of driver mutations within this population.
These findings suggest that oncologist perception of pre-test probability, rather than a systematic approach, is heavily influencing testing decisions. This is a concerning trend, as relying solely on pre-test probability can lead to missed opportunities for identifying actionable mutations and delivering personalized treatment.
Survival Impact: A 74% Increased Risk of Death
The study demonstrated a compelling link between biomarker testing and survival. Patients who did not receive biomarker testing experienced a 74% increased hazard of death compared to those who did. This association remained significant even after rigorous statistical adjustments for a wide range of potential confounding factors, including:
age
Sex
Race and Ethnicity
Socioeconomic Status
Comorbid Conditions
Insurance Type (public vs. private)
Treatment at a National cancer Institute (NCI)-designated Cancer Center
Number of Metastatic Disease Sites
The magnitude of this effect,second only to the impact of older age,strongly suggests that lack of biomarker testing is a significant driver of worse overall survival in this patient population. Importantly, the study found no correlation between insurance coverage and testing rates, debunking the common concern that payer restrictions are a primary barrier.
Addressing the Challenge: Practical Steps for Oncology Practices
To ensure equitable access to biomarker testing and improve patient outcomes, oncology practices must proactively implement systemic changes. Here are several key strategies:
Reflexive Testing: Implement routine, reflexive biomarker testing for all new tissue diagnoses of non-small cell lung cancer at the pathology level. This removes the onus from the oncologist and ensures testing is automatically initiated.
Liquid Biopsy Integration: Incorporate routine liquid biopsy (blood-based) testing as a complementary approach to tissue testing, particularly when tissue samples are limited or unavailable.
Multi-Layered Checks & Balances: Establish robust internal processes to ensure testing is ordered and completed. Leverage the expertise of nursing staff to proactively identify and address gaps in testing. In the study institution, nurses played a crucial role in catching missed testing orders.
Provider Education: Focus on educating oncologists about the importance of universal testing for all stage IV non-squamous NSCLC patients, regardless of pre-test probability.Emphasize that identifying even rare mutations can significantly impact treatment decisions.
Transparency in Pricing & Coverage: Advocate for greater transparency in pricing and coverage policies from payers to alleviate concerns about cost and accessibility.
The Path Forward: A Call to Action
This research serves as a critical wake-up call for the oncology community. Addressing these disparities requires a concerted effort from institutions, providers, and payers. By prioritizing equitable access to biomarker testing, we can unlock the full potential of precision medicine and improve outcomes for all patients with advanced NSCLC.
Reference:
Singhal S, Keegan T, Riess J, Parikh-Patel A, Hofer B, Maguire FB. Stage IV nonsquamous non-small cell lung cancer (NSCLC) biomarker testing disparities and outcomes: a population-based study. Presented at: 2025 World Conference on Lung Cancer; September 6-9, 2025; Barcelona, Spain. Abstract P1.17.03.
*Key improvements made to achieve E-E
