Comprehensive Genomic Testing Reveals Treatment Targets In 90% Of Advanced Solid Tumors

Patients with advanced solid tumors often face limited treatment options, in part because conventional testing methods fail to detect many of the genetic mutations that could guide targeted therapies. Many significant alterations occur at low levels and may be missed by simpler diagnostics, leading to missed opportunities for personalized care. Additionally, standard DNA testing can overlook gene fusions—unusual genetic events that can drive cancer growth—leaving clinicians without crucial information to inform therapy planning. The need for comprehensive, sensitive, and inclusive molecular testing is critical in ensuring that subtle but therapeutically relevant mutations are identified. Now, a new study has revealed that over 90% of tumor samples contained genetic changes that could help guide treatment decisions, offering new hope for personalized cancer care.

The study, led by Exact Sciences (Madison, WI, USA), utilized the company’s OncoExTra assay to analyze over 10,000 advanced solid tumor samples. The research covered 31 types of cancers, including breast, prostate, colorectal, lung, and ovarian. The OncoExTra assay integrates both DNA and RNA sequencing to provide a full molecular profile of each tumor. This dual approach is particularly valuable in detecting gene fusions and other events that may not be apparent through DNA sequencing alone. According to the findings, published in Oncotarget, 29.2% of samples had biomarkers linked to on-label treatments, while 28.0% were associated with off-label therapies.

Image: The OncoExTra assay uses whole-exome, whole-transcriptome sequencing across ~20,000 genes to fill in the blanks left by fixed-panel tests (Photo courtesy of Exact Sciences)

Additionally, 7.5% of samples contained gene fusions, reinforcing the importance of including RNA sequencing in molecular diagnostics, which helped identify high rates of gene fusions in prostate cancer and certain sarcomas. The results validate the assay’s ability to detect a wide range of clinically relevant genomic alterations, including rare or low-level mutations and fusion events. By identifying these genetic events, the test paves the way for precision therapies and improved patient outcomes. This advanced testing method reveals treatment opportunities even in advanced cancers, potentially guiding more personalized cancer care in real-world clinical settings.

Related Links:
Exact Sciences