Sunday, March 6, 2011

Early Detection of Ovarian Cancer

In 2010, over 21,000 women were diagnosed with Ovarian Cancer, and almost 14,000 women died from it. Three out of four women who are newly diagnosed with ovarian cancer will already be in Stage 3 or Stage 4, and only 25% of these women will be expected to live 5 more years. Furthermore, there are almost no specific symptoms for ovarian cancer. This is why ovarian cancer is so scary to so many women.
Diagnosis of Ovarian Cancer
Currently, the only way to diagnose ovarian cancer is to undergo abdominal surgery. There is no biopsy for ovarian cancer. Imaging studies lead to suspicion for cancer, but they cannot make the diagnosis. Due to the risks of surgery, avoiding unnecessary surgery is very important when attempting to diagnose early ovarian cancer. Knowing who to operate on and who to watch closely is a challenge for the ob/gyn physician.
Is there a way to screen for ovarian cancer?
Women know that a pap smear is an excellent way to screen for cervical cancer. Why is that? Because abnormal cells on a pap smear can be identified, leading to simple yet effective treatment that will prevent cervical cancer from developing. This is the ideal screening test.
A mammogram is a very good screening test, but not as good as a pap smear. Why? Because a mammogram will still diagnose cancer rather than finding a treatable precancerous condition. But, breast cancer can be diagnosed in a very early state, Stage 1, leading to less invasive treatments and very good long-term survival. Also, many women check themselves for breast lumps, leading to another method for diagnosing early stage breast cancer.
Unfortunately, there is still no pap smear or mammogram equivalent for the early diagnosis of ovarian cancer. The key for women is early suspicion. This is how we can diagnose ovarian cancer at an earlier stage.
Could these vague symptoms actually be due to Ovarian Cancer?
Is ovarian cancer a silent disease, one that shows up without any warning? Perhaps not. In one study of woman diagnosed with ovarian cancer, 70% of women had symptoms for up to 3 months prior to being diagnosed. Further studies have identified symptoms that might be due to early ovarian cancer. These are: increased abdominal size, bloating, feeling full easily, increased urge to urinate and pelvic discomfort or pain. If these symptoms occur 12 or more times in one month, the chances are still very low that these symptoms are due to cancer, but seeing the doctor is advisable.
What about using routine vaginal ultrasound?
Many studies have been done to using routine vaginal ultrasound as a way to diagnose early ovarian cancer. The results have been disappointing. In some studies, hundreds of women were identified as possible ovarian cancer and underwent surgery. Only 1% actually had cancer. In one study of 10,000 women, 300 underwent surgery. One woman had ovarian cancer, and one died from complications of surgery.
What about the CA 125 test?
CA-125 has been around for over 15 years. Gildna Radner (1946-1989), a famous comic and wife of Gene Wilder was diagnosed with ovarian cancer in 1985. It took almost a year before doctors made the diagnosis. Despite aggressive treatments, she died in 1989. Her name is often linked to the CA 125 test. If only they had done this test, they might have diagnosed her cancer sooner!
The reality is much more frustrating. We know a lot about CA 125. It is called a tumor marker, a chemical in the blood associated with the presence of cancer in the body. CA 125 is elevated in 80% of women with ovarian cancer (which means it is negative in 1 out of 5 women who have ovarian cancer). Unfortunately, CA 125 is elevated in many other conditions including endometriosis, fibroids and colon diseases like inflammatory bowel disease. Further, it is often elevated in women prior to menopause for no reason at all. Therefore, CA 125 is NOT considered a useful screening test for ovarian cancer.
A new test – the OVA1
Researchers have been looking for years for a better blood test that the CA 125. Recently, the FDA-cleared OVA1 test has become available. This test measures five different chemicals in the blood, one of which is the CA 125. It has not been approved as a universal screening test, however. The OVA1 can only be done if the patient has an ultrasound showing an enlarged ovary or an ovarian cyst. The test can help the doctor determine whether the chances are low or high that the cyst is actually a cancer.
Conclusion
There is still no FDA approved screening test for ovarian cancer. Routine ultrasound and routine CA 125 testing for low-risk women has not resulted in improved diagnosis. Women need to be aware of the combination of common symptoms that can sometimes be caused by early ovarian cancer. Your gynecologist has an array of blood and imaging tests available that often will be able to reassure you that your situation is benign and that surgery may not be necessary.
*portions excerpted from the March 2011 Committee Opinion of the American College of Ob/Gyn, Number 477.

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