Risk Factors and Causes

Scientists continue to study the genes responsible for familial ovarian cancer. This research is beginning to yield clues about how these genes normally work and how disrupting their action can lead to cancer. This information is expected to eventually lead to new drugs for preventing and treating familial ovarian cancer.

Research in this area has already led to better ways to detect high-risk genes and assess a woman's ovarian cancer risk. A better understanding of how genetic and hormonal factors (such as oral contraceptive use) interact may also lead to better ways to prevent ovarian cancer.

Prevention

New information about the extent to which BRCA1 and BRCA2 gene mutations increase ovarian cancer risk is helping women make practical decisions about prevention. For example, mathematical models have been developed that help estimate how many years of life an average woman with a BRCA mutation might gain by having both ovaries removed in order to prevent a cancer from developing. However, it is important to remember that although doctors can predict the average outcome of a group of many women, it is still impossible to accurately predict the outcome for any individual woman.

Other studies are testing new drugs for ovarian cancer risk reduction.

Researchers are constantly looking for clues such as lifestyle, diet and medicines, that may alter the risk of ovarian cancer.

Early Detection

Accurate methods for the early detection of ovarian cancer could have a great impact on the cure rate. Researchers are testing new approaches to screening, and a national repository for blood and tissue samples from ovarian cancer patients is being established to aid in these studies.

One such new approach to testing blood, called proteomics, has recently shown promise in helping to identify early cases of ovarian cancer. In this technique, unique patterns of proteins in the blood may give a clue whether or not a person has an early stage ovarian cancer.

Other researchers have suggested that a substance found in the blood, called osteopontin, may also be useful as a marker that can be tested for ovarian cancer.

Treatment

Treatment research includes testing the value of currently available methods as well as developing new approaches to treatment.

Studies continue to assess the value of laparoscopy in surgical staging with the intention of avoiding laparotomy (surgery through an abdominal incision) in some cases and minimizing the recovery period after surgery. New combinations that include recently developed drugs such as topotecan and gemcitabine are being tested. Monoclonal antibody drugs that are designed to block oncogene products (such as the HER2 protein) and slow cancer cell growth are being studied in clinical trials.

Another area of investigation involves giving very high doses of standard anticancer drugs, and then "rescuing" the woman from the side effects with infusions of her own stem cells (immature blood cells that may be taken from the bone marrow or removed from the bloodstream by using a special filtering process).

The bone marrow or peripheral (circulating) blood stem cells are removed before high doses of chemotherapy are administered and are returned to the woman after the high-dose treatment is complete. In that way, the side effect of suppressed blood cell production is overcome.

This is an extremely high-risk, experimental procedure because, for the time, the woman is without her normal supply of blood cells and is very vulnerable to infection. It is also a costly procedure that is not available in many community hospitals and may not be covered by all health care plans. Because bone marrow/stem cell transplantation is considered experimental, a woman seeking this treatment should do so in a clinical trial.

Gene therapy is also being studied. Defective tumor suppressor genes are known to promote abnormal growth and spread of ovarian cancer cells. Researchers are testing ways to package normal genes into viruses. The viruses are then modified to infect cancer cells, replace the normal genes, and restore normal growth control.

Another gene therapy strategy is to target new viral genes in cancer cells. Cancer cells containing the viral gene would then become susceptible to being killed by antiviral drugs that do not harm the normal cells.

A variety of immunotherapy strategies intended to boost the immune system's ability to destroy ovarian cancer cells are being tested. One approach is the use of cytokines (protein-like substances that activate immune system cells). Several of these substances such as interferon, interleukins, and tumor necrosis factor are being tested.

Another approach is to develop tumor vaccines that program the immune system to better recognize cancer cells. Also, antibodies that specifically recognize and attack ovarian cancer cells are being developed. Perhaps some or all of these approaches along with chemotherapy will lead to cures for this disease.

For cancers to grow, blood vessels must develop to nourish the cancer cells. This process is called angiogenesis. New drugs are being developed that may be useful in stopping ovarian cancer growth by preventing new blood vessels from forming. Several of these drugs are being tested in clinical trials, and trials of new, more potent, antiangiogenesis drugs are expected to begin soon.

Revised: 09/08/2004