A new blood test offering faster, more accessible lung cancer diagnosis is showing promising results in Brazil, perhaps offering a blueprint for global implementation. Researchers at the Hospital de Amor have demonstrated the efficacy of liquid biopsy in identifying key genetic mutations associated with non-small cell lung cancer (NSCLC), even in asymptomatic patients. The study, published in Molecular Oncology, highlights the potential to accelerate treatment decisions and improve outcomes for a disease that remains the leading cause of cancer death worldwide.
A new study suggests that a simple blood test, known as liquid biopsy, could significantly speed up lung cancer diagnosis and treatment decisions in Brazil and potentially worldwide. Early detection is crucial for improving outcomes in lung cancer, a disease that remains a leading cause of cancer deaths globally.
Research supported by the Fapesp foundation and published in the journal Molecular Oncology demonstrates the ability to identify key genetic mutations in blood samples from patients with non-small cell lung cancer (NSCLC). The study, conducted at the Hospital de Amor, a leading oncology center, analyzed circulating tumor DNA (ctDNA) in various patient groups, including those without noticeable symptoms.
NSCLC accounts for approximately 85% of all lung cancer cases. Within this category, subtypes like adenocarcinoma and squamous cell carcinoma exist. Adenocarcinoma, in particular, is often driven by specific genetic mutations that have become targets for tailored therapies, dramatically changing treatment approaches over the last decade. Just over ten years ago, the median survival rate was less than eight months; now, with targeted therapies, overall survival can range from two to three years, and even reach ten years in some cases.
“Adenocarcinoma is the subtype of lung cancer that has benefited the most from advances in genomics, and therefore it was the primary focus of our study,” explained Letícia Ferro Leal, a researcher involved in the study. “Genes like EGFR, ALK and KRAS have what we call ‘actionability.’ This means that when we identify an alteration in these genes in a patient, there’s a targeted drug available that can act directly on it.”
The study examined plasma samples from 30 patients, with 32 samples analyzed in total. Most participants hadn’t yet begun treatment, but the group also included patients who had been previously treated and four individuals participating in a lung cancer screening program. Researchers used a commercially available panel to screen for 11 genes linked to tumor development and searched for mutations. The results were promising: 65.6% of samples showed mutations, a rate that climbed to 87.5% among patients who had previously undergone therapy.
The most common mutations were found in the TP53 (40.6%), KRAS (28.1%), and EGFR (12.5%) genes. While TP53 is frequently mutated across various cancers, there isn’t currently a specific drug to target it. However, alterations in EGFR and a specific KRAS mutation (p.G12C) *are* actionable, with several approved medications available for EGFR in Brazil. The study also identified one sample with the EGFR p.T790M mutation, which is linked to treatment resistance.
“This type of mutation can emerge even in patients who initially respond well to treatment,” Leal noted. “However, it’s often detected when the patient has already experienced disease progression. The same is true for patients with mutations in other genes treated with other targeted therapies. This remains a significant challenge in oncology.”
A particularly noteworthy finding came from the screening group: one asymptomatic participant showed a TP53 mutation six months before a cancer diagnosis. Researchers believe this highlights the potential of liquid biopsy as a complementary tool for screening high-risk populations, such as current and former smokers.
Time is of the Essence
In clinical practice, Leal explained, the key advantage of liquid biopsy for lung cancer is the speed of results. Traditional analysis of tumor tissue obtained through biopsy or surgery can take weeks, encompassing sample collection, processing, pathology evaluation, and report release. Liquid biopsy significantly shortens this timeline.
“Time is a critical factor when it comes to lung cancer,” she said. “When we perform a tissue biopsy, we need to consider the time the patient waited to schedule the procedure. Only after that period does the processing and molecular analysis begin. Even in the best-case scenario, the report takes around two weeks from sample collection. With liquid biopsy, we can collect the sample at any time and have results in as little as two days, accelerating the start of treatment.”
Beyond speed, the study revealed another benefit: the panel successfully detected ctDNA even in frozen samples, eliminating the need for specialized tubes or immediate transport to specialized laboratories. This could broaden access to the method in public health settings, which may lack complex testing infrastructure.
Cost Remains a Hurdle
Despite the promising results, Leal acknowledged that integrating liquid biopsy into the Brazilian public health system faces significant economic obstacles. The test used in the study costs approximately R$ 6,000 (roughly $1,200 USD) per patient. While the price may decrease with increased competition among genetic sequencing companies, the cost remains prohibitive for many.
In the private sector, several targeted therapies are available through the National Health Supplementary Agency (ANS) formulary. However, access to these options within the Unified Health System (SUS) is limited to a few reference centers, and even those centers often struggle to offer routine molecular testing. “Sometimes, the patient can even afford the test, but can’t afford the therapy, which can cost up to R$ 40,000 (approximately $8,000 USD) per month. That’s why there are still many cases of legal challenges,” Leal commented.
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