A recent study appearing in Cancer Cell details an alternative liquid biopsy approach to detect lung cancer, with 90% accuracy. The researchers in Netherlands have designed a novel method that could diagnose non-small cell lung cancer with close to 90% accuracy by detecting tumor RNA absorbed by circulating platelets, also known as thrombocytes.
Platelets are short-lived blood cells known to form blood clots in response to injury. They also respond to a range of inflammatory events and cancer, and since they don’t have a nucleus of their own, all RNA found in platelets either comes from megakaryocytes or from RNA the platelets absorbed while circulating in blood. Platelets in a cancer-free person will contain a different compilation of RNA than platelets that interacted with a tumor, known as tumor-educated platelets.
Therefore, the scientists studied blood samples of more than 700 people, which included people diagnosed with late-stage non-small cell lung cancer, a smaller group with early stage cancer, and a control group with no known cancer. Using their technique of blood biopsy named thromboSeq, they scanned the approximately 5,000 different RNA molecules found in platelets, continuously optimizing its panel of RNA genes, arriving at the few that indicate a cancerous
tumor. Then, the researchers ran screening tests of the blood samples to see how accurately they could diagnose cancer.The thromboSeq test was found capable of diagnosing early-stage cancer with 81% accuracy and late-stage cancer with 88% accuracy. In a validation control group matched for age, smoking status, and blood storage time, the algorithm yielded an accuracy up to 91%.
“Ultimately, the aim of liquid biopsy-based cancer detection is to detect all cancers at once in an early stage; an all-in-one test,” says first author Myron Best, a researcher at the department of Neurosurgery of the VU University Medical Center in Amsterdam and the Cancer Center Amsterdam. “ThromboSeq might not only provide lung cancer diagnostics, but potentially any other tumor type as well, and may enable tumor-type stratification.”
“Although the tumor-educated platelets blood test does not, so far, provide perfect predictions, it may complement alternative liquid biopsy bio-sources such as cell-free DNA, extracellular vesicles, circulating proteins, and circulating tumor cells as well as imaging modalities such as CT scans,” Best says.
In the future, Best and colleagues plan to optimize their algorithm with more samples and tests in people who are suspected to have lung cancer but are not yet diagnosed.
“We also aim to further understand the biological mechanism responsible for platelet education in the presence of cancer,” he says.
