A new blood test that can detect several types of cancer and pinpoint their source has been developed. Johns Hopkins University researchers focused on eight cancer types: breast, colorectal, esophagus, liver, lung, ovary, pancreas, and stomach. These cancers are rampant in Western populations, and currently there are no accurate blood-tests for their early detection.
Blood Test: Accuracy Is The Key To Early Cancer Detection
For many types of cancer, the earlier the cancer is detected, the more successful treatment is likely to be. That’s why doctors suggest cancer screening tests such as mammograms to detect breast cancer and colonoscopy to find colorectal cancer. Regularly scheduled screening tests can detect cancer before any symptoms develop.
Researchers have been working to develop tests that can detect bits of tumor material in bodily fluids such as blood or urine. These tests, sometimes referred to as liquid biopsies, could potentially be used to catch cancers much earlier, long before serious symptoms appear.
Blood Test: Introducing CancerSeek, A targeted blood test
Johns Hopkins University researchers developed the blood test, CancerSeek, which evaluates the presence of 2,001 genetic mutations and levels of eight proteins. The blood test detects several types of cancer and pinpoints their source. 1,005 patients who had been diagnosed with cancer but whose cancers hadn’t yet spread at the time of enrollment were tested. They tested 812 healthy controls for comparison.
Biomarkers known for their ability to detect signs of solid tumors in the blood before they spread to other parts of the body were evaluated. They also searched for the most effective combination of known mutations to identify cancers using pieces of DNA in the bloodstream that have been released from cancer cells. In addition protein biomarkers were examined, since many early-stage tumors don’t release detectable amounts of DNA.
Blood Test: CancerSeek Test Results
The results for CancerSeek blood tests to find early stage cancer were excellent.
Overall, CancerSEEK detected 70% of the cancers. Sensitivity ranged from 98% for ovarian cancers to 33% for breast cancers. Sensitivity varied by cancer stage: 78% for Stage III cancers; 73% for Stage II cancers; and 43% for Stage I cancers. Only 7 of the 812 people without known cancers scored positive (>99% specificity).
The scientists used machine learning to predict the cancer type in the patients who had positive CancerSEEK tests. They were able to narrow the cancer to two organs in 83% of the patients and to a single organ in 63%.
CancerSeek represents the next step in changing the focus of cancer research from late-stage disease to early disease. This blood test will save many lives.
Blood Test: CancerSeek Early Detection, Next Steps
The scientists estimate that the test will cost less than $500. The eight cancer types studied account for more than half of cancer deaths nationwide. Earlier detection could potentially reduce deaths from these diseases. However, there were several limitations to this study. Further testing is necessary to measure the accuracy and predictive value of CancerSEEK in a clinical setting.