According to a report published Wednesday by the journal Science Translational Medicine, new research has found a way to detect if a person suffers from cancer way before the first symptoms show up. Through blood tests, scientists could tell if a patient is in early stages of cancer, making it easier for them to find a way to control the disease and better chances of survival.
137 possible cancer patients performed the test called “liquid biopsy.” More than a half of showed positives results, representing an excellent likelihood to start using it to screen cancer.
Such tests are not entirely new. Many people are usually tested when they have late-stage cancer because it can help find the best treatment for them, or to identify if the cancer has returned. Nevertheless, it’s the first time doctors perform this test to find it on early stages.
Liquid biopsies tests can detect breast, colon, lung and ovarian cancer
The tests detect the different forms of DNA shed by the tumor into the blood. In these recent tests to find early-stage cancer, not only one kind appeared in the results. Among the 137 patients, many of them presented four of the biggest killer cancers: breast, colon, lung and ovarian cancer.
The hard part was trying to separate the desired DNA altered by the disease, and any other kind of genetic malformations. For example, those that occur when blood cells divide, or genetic alterations diagnosed at birth.
Also, many viri should be avoided, like the Epstein-Barr virus, which usually manifests itself with tumors. These factors could confuse doctors after getting the results because of the huge amount of infected DNA shed into the blood, instead of real cancer cells. About 20,000 men were tested, and 1,112, or 5.5 percent, had viral DNA. Out of those, 309 also had the DNA on confirmatory tests a month later. After endoscopy and MRI exams, 34 turned out to have cancer.
Doctors often perform the test to monitor how the cancer is behaving. Now, researchers are developing different versions of the test for screening cancer, besides of the well-known mammograms, colonoscopies, and other tests.
According to lead researcher, Dr. Victor Velculescu, professor of oncology at Johns Hopkins Kimmel Cancer Center, this is one of the first studies that has focused on early-stage cancers.
“There is a lot of excitement about liquid biopsies, but most of that has been in late-stage cancer or in individuals where you already know what to look for,” said Velculescu.
86 out of 137 patients had stage I and stage II cancers
Within the patients tested, the total of positive results were 86 out of 137. Some of them produced stage I results, but others had stage II cancer. The tests also proved which type of cancer each patient had, like colorectal and ovarian cancer. The doctors looked for 58 genes typically linked with these diseases so that they could be entirely sure.
Within the 137 patients with cancer, the doctors also followed other 100 with possible tumors. They found that in 82 patients, their blood presented the same altered DNA it was in the tumor tissue
Scientists also found through the tests one aggressive kind of cancer in patients: the nasopharyngeal cancer, which takes place at the top of the throat behind the nose. The early detection of cancer like this one could be extremely beneficial for a population like the U.S.’, where the disease is common.
“This work is very exciting on the larger scale” because it could be a first step at finding many ways in making tests for other tumor types, such as lung or breast, said Dr. Dennis Lo of Chinese University of Hong Kong. “We are brick by brick putting that technology into place”.
Dr. Lo is known for discovering that the fetal DNA is also found in the mom’s blood, taking a tremendous impact for creating new noninvasive testing for pregnant women.
It’s effortless to find cancer when testing the blood
Due to the vast amount of infected DNA cells presented in the blood, it’s trivial for scientists to identify if a patient has cancer. The hard part is to select the right cells within the very same huge amount.
In the study, 62 percent of people were found to have stage I cancer, and exactly four out of eight had colon cancer. However, within those who had colon cancer, 90 percent patients were found at the stage II, III or IV of the disease.
Source: Science Translational Medicine