Scientists Make Progress in Understanding Ovarian Cancer Risk

An estimated 230,000 women are diagnosed with ovarian cancer worldwide, and about 130,000 die each year making it the fifth most common cancer among women in developed countries.

Due to benign symptoms, most women are not diagnosed until after the cancer has spread causing nearly 70% of those with advanced ovarian cancer to die within five years.

Findings published in Nature Genetics journal today reveal scientists have found a region of DNA that can increase or decrease the high chance of breast cancer linked to a particular gene variant.  Two other separate studies linked this same region and four others to ovarian cancer.

Researchers analyzed the DNA of more than 10,000 women with ovarian cancer and more than 13,000 women without the disease, finding five genetic variants in regions of the genome associated with ovarian cancer risk (chromosomes 2, 3, 8, 17 and 19).

"In searching the genome, we came up with some surprises on chromosomes 2, 3, and 17," says Ellen Goode, Minnesota-based Mayo Clinic genetic epidemiologist and lead author. "While examining the usual suspects in a region on chromosome 8, we found that SNPs associated with ovarian cancer risk were located quite a distance away from those associated with risk of other cancers, which suggest that they may act through a different mechanism."

Four out of five of these variants were more common in women who had serous ovarian cancer, the most aggressive and most common form of the disease.  

Dr. Andrew Berchuck, head of the steering committee of the international Ovarian Cancer Association Consortium, said in a Duke University Medical Center news release, "These latest findings raise the possibility that in the future, women in the general population who are at the greatest risk of developing ovarian cancer because they carry these newly discovered DNA variants can be identified and given closer surveillance to look for early signs of ovarian cancer when it is most treatable."

In the other two studies, scientists reportly found a region on chromosome 19 that affects ovarian cancer risk, and that variation in this same region on chromosome 19 also increases the risk of breast cancer in women who already carry a faulty copy of the BRCA1 gene on chromosome 17.  Previously research has shown that mutations in the BRCA1 and BRCA2 genes can greatly increase the risk of breast and ovarian cancer.  

"I think that the most important message women can take away from this work is that we are making progress in understanding ovarian cancer," Paul Pharoah, of Cancer Research UK Center for Genetic Epidemiology at Cambridge University, and senior author on two of the studies, said in the news release.

"We are slowly but clearly leading toward a time when we will be able to draw an individualized profile of a woman's risk of ovarian cancer and respond with appropriate prevention and treatment options," Pharoah added.

Early Detection of Ovarian Cancer:

Regular women's health exams: During a pelvic exam the doctor will feel the woman's organs to check their size and shape. But most ovarian tumors are hard to find early because the ovaries are deep within the body and the doctor cannot feel them easily. While the Pap test helps to find cervical cancer early, it is not really useful for finding ovarian cancer at an early stage.

Early cancers of the ovaries tend to cause somewhat vague symptoms which might include:
    * swelling of the stomach (abdomen) or bloating caused by a build-up of fluid or a tumor
    * pelvic pressure or stomach pain
    * trouble eating or feeling full quickly
    * having to urinate often or feeling like you have to go right away

When these symptoms are caused by ovarian cancer, they tend to go on and are a change from normal -- for example, they happen more often or get worse. If you have symptoms that you can't explain nearly every day for more than a few weeks, talk to your doctor right away.

By the time ovarian cancer is thought of as a possible cause of these symptoms, it may already have spread beyond the ovaries. Also, some types of ovarian cancer can quickly spread to the surface of nearby organs.  Dealing with symptoms right away can improve the odds of finding the cancer early and treating it with success.

Other symptoms of ovarian cancer can include those listed below.
    * Tiredness
    * Upset stomach
    * Back pain
    * Pain during sex
    * Constipation
    * Menstrual changes

Women who have a high risk of ovarian cancer, such as a stong family history of the disease may undergo ultrasound, blood tests and physical exams even in the absence of symptoms in an effort of early detection.

Risk Factors for Ovarian Cancer:
    * Obesity
    * Fertility drug usage for over 1 year
    * Not having children
    * Androgens (male hormoens)
    * Estrogen replacement therapy and hormone replacement therapy
    * Family history of ovarian cancer, breast cancer or colorectal cancer
    * Smoking and alcohol use