New blood test can detect over 50 types of cancer
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LUGANO, Switzerland — A new “all-in-one” blood test can detect more than 50 different types of cancer. In a new report, researchers with the European Society for Medical Oncology say the new screening test, which takes 10 days to process, often detects cancer before symptoms appear. It can even pinpoint where in the body a cancerous tumor is located.
Estimates from the National Cancer Institute show over 1.8 million new cancer cases were diagnosed in the United States in 2020. More 600,000 people died from the disease. In many cases, catching the cancer early can mean the difference between life and death.
However, for some of the most deadly cancers, such as liver, pancreatic, and esophageal, screening tests are not always available. Now, scientists have come up with a way which can detect all sorts, including those cancers which evade normal screenings. The company behind the research, GRAIL, Inc., has already made the test available in the U.S. by prescription only or to complement other screening methods.
“Finding cancer early, when treatment is more likely to be successful, is one of the most significant opportunities we have to reduce the burden of cancer,” says lead author Dr. Eric Klein, chairman of the Glickman Urological and Kidney Institute, in a media release. “These data suggest that, if used alongside existing screening tests, the multi-cancer detection test could have a profound impact on how cancer is detected and, ultimately, on public health.”
How does the new test work?
During the test, doctors take a blood sample from the patient and scan it for DNA, known as cell-free DNA (cfDNA), which tumors shed into the blood. Scientists then use genetic sequencing to detect whether any chemical changes to the DNA are taking place, a process called methylation.
The results then pass through a computer algorithm which checks for any abnormal patterns in methylation, a sign cancer may be present. The test also can determine where in the body the cancer is located with results available within 10 business days of the sample reaching the lab.
Catching most cancers in their early stages
To determine its effectiveness, the researchers conducted a trial involving 2,823 cancer patients and 1,254 healthy individuals. The test detected signals for more than 50 different types of cancer across all four stages of the disease. Stage I is when the cancer is still small and only in one area, whereas stages II and III mean it has spread to nearby tissue, and stage IV to other parts of the body.
Results show the test’s sensibility – or ability to identify when cancer was present – is accurate in 67.6 percent of cases across stages I through III for 12 types of cancer. These account for two-thirds of all cancer deaths in the U.S.
For all cancers, detection improved with each cancer stage, from 16.8 percent at stage I to 90.1 percent at stage IV. The test’s sensitivity is also twice as high when detecting solid tumors for which there are no other screening options – 65.6 percent compared to 33.7 percent. Also, it identified the body tissue in which the cancer was growing correctly in 88.7 percent of cases.
“We believe that cancers that shed more cfDNA into the bloodstream are detected more easily,” Dr. Klein adds. “These cancers are also more likely to be lethal, and prior research shows that this multi-cancer early detection test more strongly detects these cancer types. Cancers such as prostate shed less DNA than other tumors, which is why existing screening tests are still important for these cancers.”
Making cancer detection easier for low-income communities
The researchers are continuing to collect data from large prospective studies still taking place in America. GRAIL is also establishing a partnership with the United Kingdom’s National Health Service to conduct a trial involving 165,000 patients later this year.
“These data add to a growing body of literature that supports the use of next-generation sequencing for the detection of cell-free DNA in blood samples as a tool for earlier detection of common cancers that account for a significant number of deaths and other health problems worldwide,” Dr. Klein concludes. “In addition, a screening test that requires only a simple blood draw could provide an option for communities that have poor access to medical facilities. I’m excited about the potential impact this approach will have on public health.”
Can a Blood Test Help Diagnose and Treat Bipolar Disorder?
- Doctors currently diagnose bipolar disorder with a clinical examination.
- Recent studies have explored the levels of brain-derived neurotrophic factor in blood samples in cases of bipolar disorder and major depressive disorder.
- A new blood test could support a clinical diagnosis of bipolar disorder. However, the diagnostic criteria remain unchanged.
Recent studies have given new hope of a potential test to diagnose bipolar disorder based on levels of a molecule in the blood. This research shows promise for future developments, although clinical evaluation will likely remain the cornerstone of diagnosis and treatment in the near future.
Researchers don’t know the root cause of bipolar disorder. It appears to be influenced by a combination of a few factors:
- Genetics. Certain genes may predispose people to bipolar disorder. Someone is more likely to develop it if they have a close relative with bipolar disorderTrusted Source or depression.
- Brain structure and function. Brain chemicals like norepinephrine, serotonin, and dopamine play a role in many neurological differences, including psychiatric and mood differences. Researchers have also found that the size and structure of some parts of the brain might be slightly different in those with bipolar disorder, according to the National Alliance on Mental Illness.
- Stress. Significant stress can trigger mania in someone with genetic predisposition. A divorce, financial problems, major illness, and the death of a loved one are all examples of stressors that may lead to the onset of bipolar disorder.
As doctors learn more about what causes bipolar disorder, there may be new advances in diagnosis and treatment.
Doctors diagnose bipolar disorder on the basis of a clinical evaluation. It may consist of an interview and discussion about experiences, symptoms, and progression of those over time. There must be at least one episode of mania or hypomania for a diagnosis of bipolar disorder. Doctors then assess the severity of those episodes to determine the type.
A doctor may also perform a physical exam and run blood work. They do this to rule out other potential causes for symptoms aside from bipolar disorder.
One major challenge for doctors is distinguishing between unipolar and bipolar depression. Unipolar depression is also called major depressive disorder (MDD) and has the same criteria as bipolar depression. History of mania or hypomania along with depression is part of the diagnostic criteria for bipolar disorder, of which there are several types.
Your doctor can’t diagnose bipolar disorder from a brain scan or blood test. However, new research has uncovered a possible link between the expression of a key brain molecule and the diagnosis of mood disorders.
Blood testing as a basis for the diagnosis of bipolar disorder or depression is still in its early stages. But there has been promising research in the past few years.
Recent studies have explored the role of brain-derived neurotrophic factor (BDNF). This molecule has a big impact on learning and memory. Its expression, however, is complex. Scientists have found links between mood disorders and the levels of proBDNF and mBDNF in the blood.
A 2017 studyTrusted Source of 105 participants found levels of mBDNF in the blood of people with bipolar disorder was lower than in those with MDD. Further, the ratio between mBDNF and proBDNF in the bipolar disorder group was also lower than in those with MDD.
The researchers noted this was a promising development, as people with bipolar disorder are often misdiagnosed with MDD. A blood test therefore could help identify those with bipolar disorder experiencing depressive episodes.
A 2021 study of a new assay test showed it’s possible to diagnose low blood mBDNF levels in people with MDD or bipolar disorder within an accuracy rate of 80 to 83 percent.
It may seem like an exciting development that a simple blood test can potentially diagnose bipolar disorder. But when asked if a blood test can provide conclusive evidence of bipolar disorder, Dr. Jeffrey Ditzell, a psychiatrist in private practice in New York City, answers in the negative.
“Not yet. The test assay is currently being used to differentiate proBDNF that is potentially neuroinflammatory, from (mature) mBDNF that is considered neuroprotective,” Ditzell told Healthline.
The test uses a cutoff for serum mBDNF levels of fewer than 12.4 nanograms per milliliter. This represents progress from previous tests, offering support for a clinical diagnosis of MDD or bipolar disorder.
However, Ditzell goes on to say that the blood test is unlikely to shift the diagnostic criteria for bipolar disorder in the near future.
“The BDNF levels can be helpful, but the diagnosis of the condition of bipolar disorder remains a clinical one, and the tests, though supportive, should not be considered as confirmatory, at this time.”
Treatment for bipolar disorder often involves a combination of medication, psychotherapy, lifestyle changes, social and family support. It can take some time to find the right medication.
From this perspective, the idea of a blood test for bipolar disorder can offer some hope. The 2021 study found mBDNF levels were higher in those taking antidepressants. This suggests that perhaps a blood test can assess the effectiveness of some medications.
When asked if people with bipolar disorder undergoing treatment should ask for this kind of blood testing, Ditzell explains that the tests need further development.
“I don’t think we are there yet, but may hopefully be there in the future,” said Ditzell. “I would not rush out to ask for such a test, as it currently is of limited diagnostic value and may well be cost-prohibitive.”
New blood test for improved frontotemporal dementia diagnostics
A new study by researchers at the University of Eastern Finland shows for the first time that blood-based measurement of glial fibrillary acidic protein (GFAP) enables distinguishing patients with frontotemporal dementia from those with primary psychiatric disorders or healthy individuals.
Frontotemporal dementia is the second most common cause of dementia in the working age population. Its diagnostics are complicated by the similar symptoms presented by patients with psychiatric disorders or other neurodegenerative diseases as well as the lack of reliable diagnostic tools for differentiating these patients from each other.
A new study by researchers at the University of Eastern Finland shows for the first time that blood-based measurement of glial fibrillary acidic protein (GFAP) enables distinguishing patients with frontotemporal dementia from those with primary psychiatric disorders or healthy individuals. The levels of GFAP were significantly higher in the blood of the frontotemporal dementia patients as compared to psychiatric patients or healthy individuals. Moreover, elevated blood levels of GFAP predicted enhanced brain atrophy and faster disease progression in frontotemporal dementia patients in the follow-up.
GFAP originates from the glial cells in the central nervous system, and its increased levels reflect brain atrophy and neuroinflammation. Brain-derived biomarkers are currently mainly measured from the cerebrospinal fluid (CSF) of the patients. However, the new study now indicates that ultrasensitive single molecule array (SIMOA) is a method, which allows reliable detection of GFAP also from blood samples. This is much more practical and convenient for the patients and the health care system because it reduces the need of CSF sampling and allows wider use of biomarker measurements in clinical work. Presently, identification of suitable blood-based biomarkers for the diagnostics of neurodegenerative disorders is under intensive research.
The new study also indicated that while GFAP shows good diagnostic performance on its own, its diagnostic accuracy is further increased when combined with blood-based measurements of the neurofilament light protein from the same patients.
The now published results are expected to provide new tools for improved frontotemporal dementia diagnostics. In the future, it may be possible to distinguish patients with a neurodegenerative disease from patients with other brain diseases even at the onset of the first symptoms. On the other hand, improved diagnostics will also allow better prediction of the disease progression or even assessment of the therapeutic efficacy of future treatments. This enables intervention and support for the patients and their families at the earliest time possible.