Ovarian cancer is hard to diagnose. Symptoms – which include bloating, back pain and constipation – are vague and often don’t appear until the cancer has already started to spread. At this point, treatment is more aggressive and often not as successful, and as result the survival rate for this type of cancer is low.
As a result, researchers are exploring the idea of diagnosing ovarian cancer using a liquid biopsy. This kind of test is designed to look for signs of cancer via a blood test. It may be able to detect cancer before symptoms appear and give doctors the opportunity to treat the disease earlier.
A team of scientists recently published research in which they made significant progress in developing liquid biopsies for use in ovarian cancer. They taught a computer program to look for a specific set of genetic changes that can identify when ovarian cancer is present, which could help to improve diagnosis and even survival.
Set of genetic defects are specific to cancer
Researchers have previously found that a protein called CA125 is found in the blood of women with ovarian cancer and acts as a signal that cancer is present. But using this protein for diagnosis has some limitations. It is generally only found when cancer is at an advanced stage, and it can also be detected in women with conditions other than ovarian cancer.
The researchers in the current study looked at defects in genetic material that cancer cells release into the blood. They were able to identify a set of 14 defects that were highly specific to ovarian cancer cells. They were eventually able to narrow down this larger set into a panel of 7 defects that acts like a signature.
The researchers taught a computer program to look for this signature in blood samples from women with and without ovarian cancer. They wanted to find out whether this signature could identify the women who had ovarian cancer.
Genetic signature identifies women with ovarian cancer
The researchers found that this signature was a reliable way to identify which women had ovarian cancer. In their study, every blood sample with the signature came from a woman with cancer, and every sample without the signature came from a woman without cancer. The test could even distinguish ovarian cancer from other non-cancerous ovarian conditions.
The researchers also discovered that the same genetic signature could be found in individual cancer cells, demonstrating that it is present even in ovarian cancer’s earliest stages. If technology is developed that is sensitive enough to detect the signature at extremely low levels, the test could potentially be used to detect cancer before it has started to spread.
This research identifies a potential way to diagnose ovarian cancer through a blood sample. Eventually, the test could be used to regularly monitor women at high risk of ovarian cancer in order to find cancer early, treat it at its earliest stages and save more lives.
A lot more study is necessary before this test can be routinely used, but these promising results demonstrate the technique is worth pursuing as a possible screening option.
Eileen Hoftyzer, BSc, and Carolyn Goard, PhD