Want to tackle the fifth-leading cause of cancer death in women? Start with a pencil and paper. A simple three-question survey, developed by a research team from the Fred Hutchinson Cancer Research Center, may help identify women who could benefit the most from screening tests for ovarian cancer.
Ovarian cancer is an abnormal cell growth that begins in one or both ovaries, the female reproductive organs that produce eggs. It is a relatively rare cancer, causing about 3 percent of all cancers in women.
In 2012, 22,280 women were diagnosed with ovarian cancer, and 15,500 women died from the condition – a mortality rate of 70 percent. In comparison, 76,250 cases of melanoma, the most deadly form of skin cancer, were diagnosed in 2012, while 9,180 melanoma-related deaths were recorded – a mortality rate of 12 percent; 229,060 cases of breast cancer were diagnosed, and 39,920 people died – a mortality rate of 17 percent.
Ovarian cancer is deadly because it is usually diagnosed late, when it’s hard to treat it successfully. About 70 to 90 percent of ovarian cancers can be cured if the cancer is detected when it is still confined to the ovary. However, early detection of ovarian cancer is not the norm. More than 70 percent of women with ovarian cancer are diagnosed with advanced-stage disease, at which point the survival rate is only 20 percent to 30 percent.
To Screen or Not to Screen
Technology has transformed cancer screening, making it possible to detect many cancers early, when they can be treated or cured. For many cancers, a simple blood test, often combined with an imaging test such as an ultrasound, computed tomography (CT), or magnetic resonance imaging (MRI) scan, can lead to early diagnosis – and cure.
However, ovarian cancer is a recalcitrant foe. No existing screening method has been shown to reduce the death rate from ovarian cancer, which is frighteningly high.
Excellent screening tests for ovarian cancer do exist and can help women and their physicians to detect the disease. Ovarian cancer screening tools include ultrasound scans and blood tests for biomarkers called CA-125 and HE4. HE4 is used sometimes with the CA-125 marker to help diagnose women with pelvic masses.
However, not all women are screened for ovarian cancer – nor should they be, according to experts. Ovarian cancer screening should only occur when there’s good reason for it, according to the United States’ leading think-tank on preventive services, the U.S. Preventive Services Taskforce (USPSTF). In 2011, the USPTF reviewed existing literature on ovarian cancer screening. The taskforce concluded that widespread screening for ovarian cancer, although accurate, does not appear to be effective at saving lives, and may in fact do more harm than good for most women.
The USPTF guidelines that recommend against screening women for ovarian cancer are based on some “very good research,” says Andersen. One reason not to screen for ovarian cancer is the rarity of ovarian cancer. “Ovarian cancer is very rare,” says Andersen. “Even though those tests are good, they not good enough to perform on all women without causing harm to a group of women without the disease – who are never going to get the disease – who have positive test results.”
In addition, it’s difficult to tell the difference between a benign mass in the pelvis and ovarian cancer using only imaging tests. That means surgery is the only definitive way to diagnose the disease. So many women with a false positive test may lose an ovary unnecessarily.
Testing may be appropriate, the USPTF concluded, in women who have a family history of ovarian cancer or who have a genetic predisposition for the disease. Many women in this group may still experience negative consequences of screening. Nevertheless, they are more likely to be helped, since their risk of the disease is so much higher. Women who have symptoms also stand to benefit from the tests. Because they have symptoms, they are much more likely to have the disease – and the potential harms of testing are less of a consideration.
A Low-Tech Solution
So if biomarker and ultrasound screening for all women is not recommended, and family history only accounts for a small fraction of women who develop ovarian cancer, how do you identify women with the disease before it is too late? That’s where the pencil and paper, a few minutes of reflection, and three questions come in, says Andersen.
Andersen’s team set out to identify women who might benefit from screening even if they didn’t have a family history of ovarian cancer. Instead of turning to laboratories and genomics, they turned to a primary care clinic and the women in the waiting room.
Investigators developed a survey based on a symptom-screening index developed in 2006 by Andersen and co-author Barbara Goff, M.D., professor and director of Gynecologic Oncology at the University of Washington School of Medicine.
The research team developed and tested several symptom screening surveys, finally settling on the three-question format as the most effective. The survey asked whether a woman was currently experiencing one or more of the following symptoms, all of which have been identified previously as potentially indicative of ovarian cancer:
The researchers recruited 1,200 women, age 40 to 87, for the study. All of the women were being seen in a Seattle women’s health clinic for either a health concern or a routine appointment. None were there specifically because of concerns about ovarian cancer.
Of those surveyed, 5 percent scored positively on the symptom check, indicating they needed further testing. Subsequently, one woman in this group of about 60 women was diagnosed with ovarian cancer. The vast majority -- 95 percent -- of women scored negatively on the symptom survey. No women in this group developed ovarian cancer during a year-long follow-up period. These results attest to the accuracy of the screening tool.
What are the Symptoms of Ovarian Cancer?
Symptoms can be a key tip-off that something is amiss. Indeed, 90 percent or more of women with ovarian cancer are symptomatic at the time they have surgery. Women who recognize symptoms of possible ovarian cancer and take quick action may indeed benefit from ultrasound and biomarker screening. However, for that to happen, women need to recognize – and acknowledge – their symptoms.
Symptoms of ovarian cancer may mimic many other symptoms, and women may be embarrassed to talk about them, even with their doctors. Many women may ignore them until it’s too late. “There can be a lot of discomfort,” Andersen says. “But many women are familiar with bloating; they may have had it a couple days a month since they were 18 years old. The fact that suddenly they’re feeling bloated all the time may not trigger the thought that, ‘Hey, this is completely different.’”
The key, says Andersen, is for women to notice when there’s discomfort that is completely different from what they have experienced before. Women over age 60, especially, may simply expect that their health will worsen as they age.
Women should focus on whether a symptom is new and different, explains Andersen. A new onset of daily bloating, pelvic discomfort, and difficulty eating should be checked out.
“If any of these symptoms are new and are occurring every day or every other day, for two to three weeks, a woman should talk to doctor about getting the tests,” says Andersen. A woman who recognizes her symptoms and acts upon them is more likely to be diagnosed when the cancer can still be surgically removed, that is to say when it is considered fully resectable. Although not all women with early-stage disease have symptoms, most do.
“But it’s not just that one list of symptoms, although that covers a lot of it,” she says. “I had a personal friend who just felt lopsided. It was something that stayed there, and it was new and different. She consulted with her doctor and was diagnosed with ovarian cancer. That was years ago she’s okay now. ”
In women with symptoms, says Andersen, the CA 125 blood test is an appropriate test. Ideally, the biomarker test should be used longitudinally, or over time. “The doctor should do a first blood test right away, followed by an ultrasound,” she explains. “Even if you don’t find anything, do it again. If the blood level of CA-125 is rising, that’s the real sign of a small cancer. That’s how you can find something very early.”
So is a three-question survey the last word in ovarian cancer screening? By no means. However, it does suggest that a simple, low-tech questionnaire, which is easy for both women and their doctors to navigate, can be a useful way to identify women who are good candidates for further screening.
In the meantime, research into biomarkers and other low-harm screening methods continues. “There are more biomarkers being looked at,” says Andersen. “It’s really exciting to be chasing them down. A lot of people are looking for additional markers, but the search is difficult. In the meantime, the answer may be symptoms followed by additional testing. Hopefully we’ll come up with something better in the next five years, but there don’t appear to be any in the immediate pipeline.”