The medical industry has made a variety of developments in the testing and detection of many different diseases. From cancers to allergies, there is so much to be learned from all different types of tests that weren't available years ago. While blood has the power to show us a lot of information about our bodies, it may have even more capabilities than we initially thought.
Words: Mia Barnes
image: National Cancer Institute
While blood tests have been used to detect certain conditions that easily manifest in the blood — like infections and nutritional deficiencies — scientists and doctors are realising that there doesn't need to be a clear-cut diagnosis to use blood to detect illnesses. While conditions like cancer and Alzheimer's disease are often notoriously difficult to detect in the early stages and often go undiagnosed until much later, blood testing could be the answer to getting earlier diagnoses.
There are so many things that blood can tell us about human health. With some tests still in their earlier stages, they could eventually bring about more concrete, standardised systems of testing for all kinds of illnesses and conditions. That way, treatment can begin as early as possible.
Breast Cancer
Breast cancer is one of the most common forms of cancer diagnosed in women all around the world. With a such a high diagnosis rate and mortality risk, catching it early and treating it should be a priority for at-risk groups.
Currently, the most common form of breast cancer screening is mammogram technology, which many women go for once a year — or slightly less often, depending on their age and level of risk. While mammograms are often thought to be the best available form of detection, the rates at which they show both false positives and false negatives can be risky for patients.
While blood testing isn't ready to replace mammogram technology just yet, biomarkers in blood such as proteins, autoantibodies, miRNAs, nucleic acid methylation, metabolites and lipids are all clues found in the blood. This means that doctors and scientists can use them to point towards a diagnosis, especially in the earlier stages of the condition when it often goes unnoticed by other testing methods.
While the blood testing method for breast cancer detection is still new, it is already proving itself to be a worthy contender in the conversation surrounding cancer detection.
Alzheimer's Disease
Unlike cancer, Alzheimer's disease is often diagnosed through present symptoms rather than physical or biological traits. It's a progressive condition that impacts the cognitive function of older adults as they age, often impairing memory.
While there is no cure, there are treatments available. Since the symptoms themselves are often used to diagnose the condition, this means that, unfortunately, Alzheimer's disease often gets diagnosed when the patient is already suffering. While it's never too late to treat the condition, progress in treatment is often much easier when you catch the condition early and start as soon as possible.
While factors like genetic predisposition, family history and certain imaging technologies can help people understand their risk, they can't be used as definitive diagnostic tools. However, blood may hold some new answers.
Just like biomarkers in blood testing can help diagnose patients with cancer, Alzheimer's also offers a unique set of biomarkers to help catch the condition early. Specifically, testing for the presence of a protein called p-tau217 can detect the condition better than an MRI test. While still in its early stages, blood testing shows a lot of promise when it comes to catching Alzheimer's early.
Various Forms of Cancer
Image: National Cancer Institute
Although breast cancer is one of the main cancers studied thus far in terms of testing for biomarkers and using them to direct towards a diagnosis, it isn't the only type of cancer that could benefit from blood testing.
In fact, recent studies have found that at least 10 cancer types can potentially be detected through blood testing. Among them are lymphoma, appendix, uterine, thyroid, kidney, ovary and other unidentified cancers. Blood tests seem to be particularly good at detecting localized cancers in addition to ones that are more widespread.
While it isn't exactly clear which cancers can be caught by blood testing, using blood tests early on — especially in conjunction with other forms of testing — can create a well-rounded profile of understanding and research around catching cancer early.
Why Blood Testing?
In short, blood testing is able to offer quicker results with more definitive answers than many of the other tests out there. For conditions like cancer, this can add another form of testing to help patients get an accurate result earlier on. For conditions like Alzheimer's, where early testing isn't as common, it could prove revolutionary in catching the condition earlier.
Blood testing is also a non-invasive form of collecting biomarkers, which makes testing easy, convenient and accessible to more people than ever before. While it isn't a perfect method yet, current research shows that it definitely has promise.
It's All in the Blood
For those looking to detect an illness or condition early on, blood testing and biomarkers could prove to be a revolutionary tool. Blood testing still has a long way to go — but who knows what else scientists will discover?