Purpose of this Study
NCI's Role and Goal
The National Cancer Institute is supporting and conducting research on the detection and prevention of ovarian cancer. Research studies called clinical trials are used by scientists to study better ways to detect and prevent ovarian cancer. NCI's overall goal is to reduce the incidence of ovarian cancer, and to diminish the pain and suffering experienced by those women who do develop this illness.
Ovarian Cancer Incidence, Mortality, Detection, and Risk
In 2004, it is estimated that more than 25,500 women in the United States will develop ovarian cancer, and more than 16,000 will die of this disease. The sooner ovarian cancer is found and treated, the better are a woman's chances for recovery and long-term survival. But ovarian cancer is hard to detect early. Many times, women with ovarian cancer have no symptoms or just mild symptoms until the disease is in an advanced stage. Women who are at increased genetic risk of ovarian cancer are of particular concern, because their lifetime risk of developing this cancer is so much higher than the risk experienced by women in the general population.
Seeking the Answers to Important Questions
Although surgical removal of the [glossary term:] ovaries and the [glossary term:] fallopian tubes appears to greatly reduce the chance that high-risk women will develop an ovarian cancer-like illness, there are still many important questions, which need to be answered. These include:
- By how much does surgery reduce ovarian cancer risk?
- By how much does surgery reduce breast cancer risk?
- How does risk-reducing surgery affect quality of life for those women who choose this approach?
- What factors influence a woman's decision about which of these two management approaches to choose?
- How does premature (earlier-than-usual) menopause affect the risk of developing the general medical problems that are more common in postmenopausal women, such as osteoporosis and cardiovascular disease?
- Are there detectable abnormalities in the ovaries of high-risk women which might allow diagnosis at the earliest stages of the [glossary term:] malignant process?
- How does the cancerous process actually occur at the cellular and molecular levels in high-risk women?
A Different Approach to Ovarian Cancer Prevention Research
Most of the current information related to these questions is based on studies that look back in time to evaluate high-risk women, studied in highly-specialized cancer genetics clinics at major medical centers. This type of information may be less accurate and less applicable to the entire population of high-risk women than we would prefer.
The Ovarian Cancer Prevention and Early Detection Study is a [glossary term:] cohort study that will collect data going forward in time (i.e., prospectively) from women seen at both large and smaller medical centers across the U.S. It is hoped that this research approach will produce information that is more precise, and more representative of all high-risk women. Its emphasis on evaluating quality of life and on collecting biological samples for future laboratory-based research related to ovarian cancer are also special strengths of the current study's design.
The Challenge: Detecting Ovarian Cancer Before Symptoms Develop
Currently, there is no effective approach to [glossary term:] screening for ovarian cancer, either for women in the general population or for high-risk women. Because the risk of ovarian cancer is so much higher than normal in genetically at-risk women, they have been selected as a population that is in particularly great need of an effective ovarian cancer screening strategy.
Using CA-125 Levels
The Ovarian Cancer Prevention and Early Detection Study is evaluating a new approach to using the level of [glossary term:] CA-125, a substance called a [glossary term:] tumor marker, which is often found in higher-than-normal amounts in the blood of women with ovarian cancer, as a means of screening for ovarian cancer. The new approach is based on looking at changes in the levels of CA-125 over time as the basis for deciding whether or not additional tests are needed to look for ovarian cancer. This method uses a mathematical, computer-based tool known as "ROCA," the Risk of Ovarian Cancer Algorithm. This will be the first time that the ROCA screening tool has been used in a clinical trial.
The important questions related to the screening portion of this study include:
- Does ROCA hold promise as an improved ovarian cancer screening strategy?
- How is ROCA affected by other characteristics of the women being screened, such as age, prior pregnancy, and various medications?
- Are there new tumor markers (either proteomic or biochemical) detectable in the blood samples that are being collected as part of this study which might, either alone or in combination, be more effective in detecting the presence of early ovarian cancer than CA-125?
The Ovarian Cancer Prevention and Early Detection Study is expected to produce very valuable information regarding these and other questions of great importance to women who are at increased risk of ovarian cancer. We cannot promise that taking part in this study will benefit each of the women who join, but their participation is likely to teach us a great deal about how familial ovarian cancer develops, and help improve the management options that are available to future high-risk women.