A POSSIBLE NEW OVARIAN CANCER TEST AND PROBLEMS DEVELOPING DIAGNOSTIC TEST TO DETECT OVARIAN CANCER AT AN EARLIER MORE CURABLE STAGE
What tests are available to detect ovarian cancer and concerns about a new blood test for ovarian cancer
A problem with ovarian cancer is that it may not be detected until an advanced stage. The NY Times reported on concerns about a new test to detect ovarian cancer originally developed at Yale University called Ovasure. I had also previously written about another new test designed to sample the urine for signs of ovarian cancer. That test was from the University of South Florida. In general, the earlier a cancer is detected the easier it is to treat. Early detection is especially important for ovarian cancer. Although many people have heard of the well established CA 125 as a test for ovarian cancer detection, it has not been enough to detect it early. CA 125 is more often used as a test to follow the progress of treatment. So the search has been on for ways to detect ovarian cancer at an early stage.
According to the Times,the test from Yale, "OvaSure measures the level of six proteins in a sample of blood, some produced by a tumor and some produced by the body in reaction to a tumor. It then calculates a probability that the woman has ovarian cancer. One of the six proteins is CA-125, which is used by itself as a test to monitor disease progression in women who already have ovarian cancer but is not good at picking up early disease".
"In a study published in the journal Clinical Cancer Research in February,2008 the test correctly classified 221 of 224 blood samples taken from women with ovarian cancer or from controls. It identified 95 percent of the cancers, and its false positive rate — detecting a cancer that was not there — was 0.6 percent".
But the story goes on that there are questions about who would be good candidates for the test and the possibility of false positives. This is where the test comes back positive but in reality the person doesn't have the problem being tested for.
What are Scientists at University of South Florida Studying for Ovarian Cancer?
Scientists at the University of South Florida have been evaluating a urine test for a protein called Bcl-2 in urine as a method to detect ovarian cancer at an early stage. Bcl-2 is a chemical, a protein that may appear in greater quantities with many cancers but the USF scientists were looking at Bcl-2 in urine and it's association with ovarian cancer. Geo Pharma, a pharmaceutical company has licensed the rights to use the University of South Florida work as an early stage diagnostic urine test for ovarian cancer.
As Dr. Kruk of the University of South Florida said in an interview in 2006 "BCL-2 is a protein that normally prevents cell death. In your normal cells, there is constantly a homeostasis between cells that have to die or survive depending upon how much damage or trauma they might have experienced. For cancer cells, there are unique characteristics. Obviously cancer cells have a tendency to be able to survive in situations where a normal cell would not. As a result, the protein that we have been looking at, called BCL-2, is normally a protein that prevents cell death. We have found in a lot of other people that this protein, BCL-2, is over expressed in a lot of cancers, not just ovarian cancer, but our study has focused on ovarian cancer. Where we have found BCL-2 is expressed in high levels in the urine with women with ovarian cancer".
How is Ovarian Cancer Detected and Diagnosed?
If a woman or her doctor suspects ovarian cancer, diagnosis begins with a medical history of the patient, review of her symptoms, and complete physical examination, including a pelvic exam, in which the physician feels the vagina, ovaries, fallopian tubes, bladder, and rectum to check for any growths. A Pap test may also be done because, even though it cannot reliably detect ovarian cancer, it may detect cancer cells that have migrated to the uterine cervix from the ovaries.
Blood and urine tests may also be done, as well other procedures, depending on the woman's symptoms and results of her physical exam. Procedures that might be done in the search for ovarian cancer include:
The only sure way to diagnose ovarian cancer, however, is through microscopic examination by a pathologist of abnormal-looking fluid or tissue. While fluid can sometimes be obtained by needle aspiration or other techniques, more commonly a laparatomy or laparoscopy is done. Laparotomy is an exploratory operation in which the surgeon examines the abdomen thoroughly and removes fluid or tissue for examination. In laparascopy, a flexible, lighted tube is passed through a small incision in the abdomen, allowing the surgeon to examine the area and extract tissue for a biopsy.
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