Results show liquid biopsy developed by Ludwig Johns Hopkins team could be safely incorporated into routine clinical care in combination with conventional screening
APRIL 29, 2020, New York— Results from a first-of-its-kind study of a multicancer blood test in more than 9,900 women with no evidence or history of cancer showed the liquid biopsy safely detected 26 undiagnosed cancers, enabling potentially curative treatment. Overall, 26 cancers were detected by the blood test, while an additional 24 cancers were detected by standard screening such as mammography or colonoscopy. Together, screen-detected cancers (those detected by either blood testing or standard screening), accounted for more than half of the 96 cancers detected during the study period; the remaining were not detected by either method. Cancers detected by the blood test were most often localized by diagnostic PET-CT, and twelve of the cancers detected by the blood test could be surgically removed.
Researchers at the Ludwig Center at the Johns Hopkins Kimmel Cancer Center who developed the blood test say the study, called DETECT-A, is the first time any liquid biopsy blood test has been used clinically to screen for cancer in a population without previously detected cancer for the purpose of diagnosis and intervention—specifically, treatment with the intent to cure cancer.
A report on the work was published April 28 in Science and presented the same day at the virtual annual meeting of the American Association for Cancer Research.
The multicancer blood test detects the presence of cancer gene mutations in circulating DNA and blood levels of specific cancer proteins. This test, initially named CancerSEEK, was first reported in Science in 2018 by the Ludwig Johns Hopkins research team. Several improvements have since been made to the test, but the DETECT-A study was initiated prior to those advances.
“The DETECT-A study incorporated PET-CT imaging to provide independent confirmation of the existence of a cancer and to precisely localize its site,” says Ludwig investigator Nickolas Papadopoulos, senior author and professor of oncology and pathology at Johns Hopkins.
In the DETECT-A study, the blood test followed by PET-CT imaging was 99.6% specific for cancer. The researchers also confirmed that the genetic mutations picked up by the blood test that led to a positive test were present in the cancer 100% of the time.
“Our primary goal was to demonstrate reliability and safety—to show the blood test could lead to the diagnosis of cancers and get patients to treatment aimed at curing them,” says Kenneth Kinzler, professor of oncology and co-director of Ludwig Johns Hopkins. A secondary goal was to show that blood testing could be integrated with conventional screening methods for detecting breast, colon and lung tumors.
Combining standard of care screening with the blood test augmented the benefit of screening for these three cancer types, improving sensitivity from 47% to 71%. Blood testing also allowed the detection of seven other cancer types (lymphoma, appendix, uterine, thyroid, kidney, ovary and cancers arising from an unknown primary site) that cannot be screened now, with a sensitivity of 31%. There were some false positives as well: 101 women who tested positive with the blood test did not have cancers that could be detected by follow-up imaging or, in 22 cases, by endoscopy.
The blood tests were performed by Thrive Earlier Detection, a spin-off company established to further develop and commercialize the liquid biopsy.
Notably, 17 cancers (65%) first detected by the blood test were diagnosed at an early stage, when the cancer was still localized or regional to the area it originated. Twelve surgeries were performed with intent to cure. Of the 26 patients first detected by blood testing, 12 remain in remission and eight remain in treatment or have stable disease approximately nine months past diagnosis.
The investigators say additional studies with an optimized version of the blood test, which remains in development, are being planned. “We believe that more than two-thirds of cancers that occur in the U.S. can eventually be screen-detected, either by blood testing or standard screening, before they cause symptoms of disease. Such earlier detection has the capacity to substantially reduce suffering and death from many cancer types,” said Bert Vogelstein, co-director of Ludwig Johns Hopkins, Clayton Professor of Oncology at Johns Hopkins and a Howard Hughes Medical Institute investigator.
The Johns Hopkins news release from which this summary is derived can be found here.