“These results are an important first step in testing that can detect cancer very early,” he said Deb Schrag vom Memorial Sloan Kettering Cancer Center (New York), die I study Sunday at annual congress presented to the European Society of Medical Oncology (ESMO) in Paris.
The blood test shows “a good detection rate in people who actually have cancer (sensitivity) and excellent specificity (negative test – definitely no cancer; known) for people without malignant disease. For people with a positive test, it took less than two months to confirm the diagnosis and a little longer to rule out cancer (…), “the scientist noted.
Few cases of false positives
The study (“Pathfinder”) included 6,621 subjects aged 50 and over who had not previously been diagnosed with cancer. The test kit aimed to detect circulating genetic material (ctDNA) in the blood from malignant cells of 50 different cancer diseases.
Experts found a positive test and therefore a suspicion of cancer in 1.4%. This suspicion was confirmed in 38 percent of subjects with a positive blood test after doing additional conventional tests, such as imaging (CT, MRI), endoscopic examinations, etc.
However, the specificity rate was extremely high. Of 6,290 subjects who did not have cancer, 99.1% tested negative for ctDNA from malignant cells. Deb Schrag: “An important finding was that few participants with a false positive test also required repeated invasive investigations such as endoscopy or tissue biopsy. This should allay fears that such tests could cause harm by triggering unnecessary additional diagnostic steps in healthy individuals. “
Important for cancers without screening procedures
Such blood tests, which correspond to a liquid biopsy (liquid biopsy), could become particularly important in the screening of oncological diseases, which are otherwise often discovered too late with other methods (imaging, tissue biopsies, endoscopic examinations) and for which they exist There are still no screening methods in asymptomatic people: for example pancreatic carcinomas, carcinomas of the small intestine and stomach.
–
