The Personal Health Navigator is available to all Canadian patients. Questions about your doctor, hospital or how to navigate the health care system can be sent to AskPaul@Sunnybrook.ca
Question: A friend died of ovarian cancer. By the time it was discovered, it was too late to cure her. I recently read that American doctors are developing a new test to look for ovarian cancer. When will this test be available for the public?
Answer: What happened to your friend is, unfortunately, fairly common with ovarian cancer. About 75 per cent of cases are diagnosed when the cancer is well advanced and difficult to treat. Most patients don’t have any obvious signs of the disease in the early stages. Later on, they may experience rather vague abdominal symptoms such as bloating, indigestion, pelvic discomfort, constipation or diarrhea that can persist for months.
These symptoms are often mistaken for stomach troubles and not immediately linked to a cancer that starts in the cells of the ovaries – the pair of almond-sized organs that lie on opposite sides of the uterus or womb. (The ovaries – part of the female reproductive system – produce eggs, plus the hormones estrogen and progesterone.)
Scientists have been trying to develop a simple blood test that can help catch the cancer when it is just starting to grow. In fact, about three decades ago, researchers identified a protein, called CA-125, which is produced by ovarian tumors and ends up in the bloodstream. But the protein can also become elevated by other ailments such as uterine fibroids. That means the test can lead to a “false positive” – essentially a false alarm. In earlier studies using this test, women have had surgery to remove a mass that turned out to be a relatively harmless cyst.
Now, however, some researchers think they can reduce false positives by using a unique algorithm, or mathematical calculation, to analysis changes in CA-125 levels over a period of time.
To test this theory, researchers led by Karen Lu at the University of Texas MD Anderson Cancer Center in Houston, did an 11-year study involving more than 4,000 post-menopausal women who received yearly CA-125 tests. In total, 10 women had surgery because their test results looked worrisome when analyzed with the algorithm. Of those, four were discovered to have early stage ovarian cancer, five had tumors considered benign, and one had endometrial (lining of the uterus) cancer.
Writing in the journal Cancer, the researchers said a lot more work must done before this screening approach is ready for the general public.
I asked Dr. Allan Covens, head of gynecologic oncology at Sunnybrook Health Sciences Centre, what he thought of the U.S. study. He believes it’s promising because only a small number of women were referred to surgery. In other words, there were not many false alarms.
But a better measure of this screening approach will come from a much bigger study, involving 200,000 women, now taking place in Britain, added Dr. Covens, who is also a professor of obstetrics and gynecology at the University of Toronto. The findings will likely be released in 2015.
Even if the British results are encouraging, the CA-125 test has some well-known limitations. Not all ovarian tumors produce detectable levels of CA-125, said Dr. Covens. The test could miss up to 20 per cent of ovarian cancers, according to some estimates.
It should also be kept in mind that ovarian cancer is relatively uncommon. About 2,600 women in Canada are diagnosed with ovarian cancer each year and 1,700 die from the disease, according to the Canadian Cancer Society. By contrast, an estimated 23,800 women in Canada will be diagnosed with breast cancer this year, and 5,000 will die from the disease.
So there would need to be some thought put into how a screening test should be used. Is it practical to screen the entire female population? Or, is it possible to just screen high-risk individuals like those with a family history of the disease?
Meanwhile, as the search for a reliable test continues, Dr. Covens noted that progress has been made in extending the lives of those diagnosed with advanced disease.
“People are living a lot longer than they used to,” said Dr. Covens. “For those people who we can [surgically] remove all their visible tumor, the median survival is eight or nine years now, which is dramatically different from 10 or 15 years ago when the median survival for most patients was in the three to five year range.”
Paul Taylor is Sunnybrook’s Patient Navigation Advisor. His column Personal Health Navigator provides advice and answers questions from patients and their families, relying heavily on medical and health experts. His blog is reprinted on healthydebate.ca with the kind permission of Sunnybrook Health Sciences Centre. Email your questions to AskPaul@sunnybrook.ca
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Hello ! I have a question to ask . My mom was just diagnosed with cervical cancer stage 2. I understand and being told by medical staff at Sunnybrook hospital that to see if cancer spreading els where for example ovaries we have to wait till actual surgery to see. And now we are waiting for surgery day to be booked over 4 weeks and need to wait more because our doctor is on vacation! So my question is why No other doctors are taking patients from the doctors who is on vacations? And why ppl are have to just wait to die?!
Hi Maria:
I have a bit more information for you. I emailed your question to Dr. Allan Covens, head of gynecologic oncology at Sunnybrook Health Sciences Centre.
He replied, “we don’t do MRI routinely, unless we are suspecting a benign process, like endometriosis.”
That indicates, he added, “there is nothing … to suggest an advanced ovarian cancer.”
If the MRI result, “suggests this is endometriosis, then we will be referring [you] back for management closer to home.”
You may want to have another discussion with the members of your medical team and ask them what they think the mass might be and why they have ordered an MRI. They should be able to give you better clarity on your condition.
I hope this helps.
Paul Taylor
Hi Maria:
I can certainly understand your concerns. I think I would feel the same way you do. Your own medical team has the best knowledge of your case. You should ask your doctors about the timing of possible treatments and if it might affect your outcome. Worry is a natural response in a situation like this. Let your medical team know how you feel and what can be done to help reduce your anxiety.
Hi
I had my first visit to your clinic three weeks ago for a large ovarian mass. I know I am in the very best hands but it will still be another week before my MRI and then an addition two weeks to get my results. I am so worried that if I have this disease it will spread by the time I have surgery. I am just so concerned that from the time this mass was found, referrals, MRI and then surgery it will be three month for a disease that is aggressive and outcomes poor.