ASCO Perspective

“Detection of early-stage disease is one of the best ways to cure cancers. Although cancer screening tests currently exist, uptake around the world may be limited by cost, complexity, and scarcity. These interim results demonstrate that next generation ctDNA screening holds promise as an early detection tool in Vietnam, although additional validation of the SPOT-MAS assay is needed before this test is ready for clinical use,” said Erica L. Mayer, MD, MPH, ASCO Expert.

ALEXANDRIA, Va. — A non-invasive blood test successfully detected early-stage cancer and identified tumor location in asymptomatic individuals in Vietnam according to a new study. The research will be presented at the 2023 American Society of Clinical Oncology (ASCO) Breakthrough Meeting, taking place August 3-5 in Yokohama, Japan.

According to the study authors, up to 80% of cancer patients in Vietnam, where a nationwide cancer screening program is not currently available, are diagnosed at later stages (III or IV), leading to a low 5-year survival rate. Earlier detection can improve the chance of survival and clinical outcomes for patients with cancer.

“Common screening methods are often invasive, inaccessible, and involve separate procedures to screen individual cancer types. Affordable, accessible, non-invasive multicancer screening tests are needed for early detection, especially in a lower-middle income country like Vietnam. Our study provides clinical evidence for the applicability of the SPOT-MAS ctDNA-based assay as a complementary method in early cancer detection,” said senior study author Le Son Tran, PhD, Gene Solutions, Medical Genetics Institute, Vietnam.

The Screening for the Presence Of Tumor by Methylation And Size (SPOT-MAS) test is a liquid biopsy-based assay that was developed to test the five most common cancer types in Vietnam — liver, breast colorectal, gastric, and lung cancers. SPOT-MAS captures multiple signals of cancer from circulating-tumor DNA (ctDNA) in the blood. The study, named K-DETEK, recruited 10,000 asymptomatic participants across 14 sites in Vietnam. This interim analysis included 2,795 participants with moderate to high cancer risk who had neither clinical suspicion of cancer nor a confirmed history of cancer.

Key Findings

• SPOT-MAS detected cancer in asymptomatic participants with a positive predictive value of 60% — meaning that for every 100 people that test positive, 60 have cancer.
• The test was able to predict the location of a tumor with 83.3% accuracy, allowing clinicians to fast-track the follow-up diagnostic and guide any necessary treatment.

Next Steps

The authors are conducting a study aiming to refine the SPOT-MAS assay to expand its cancer-type coverage to include rarer cancers, such as ovarian and pancreatic cancers, that would currently be missed by the test.

This study was funded by Gene Solutions.

View the full abstract

View disclosures for the:

• Authors: https://coi.asco.org/Report/ViewAbstractCOI?id=426774
• ASCO Breakthrough News Planning Team: https://old-prod.asco.org/sites/new-www.asco.org/files/content-files/about-asco/pdf/2023-ASCO-Breakthrough-NPT-Disclosures.pdf

For your readers:

• Cancer.Net Blog Post Highlighting Research From 2023 ASCO Breakthrough
  (Please note: Link will be active after embargo lifts)
• Liquid Biopsies for Cancer: What to Know and What to Expect
• What Are Multi-Cancer Early Detection Tests and How Might They Impact the Future of Cancer Screening?
• Cancer Screening

ATTRIBUTION TO THE AMERICAN SOCIETY OF CLINICAL ONCOLOGY BREAKTHROUGH MEETING IS REQUESTED IN ALL COVERAGE.

###