Initial results of a new pilot study show that four symptoms, combined with the CA125 blood test, can greatly improve the early detection of ovarian cancer by 20%.
The study was conducted by researchers at Fred Hutchinson Cancer Research Center (Seattle, Washington) and published this week online in Cancer.
Research has found that when used alone, the CA125 ovarian-cancer blood test and a simple four-question, symptom-screening questionnaire asking if abdominal or pelvic pain, difficulty eating or feeling full quickly and abdominal bloating are present, each detect about 60% of women with early-stage ovarian cancer and 80% of those with late-stage disease.
The study found that when used together, the questionnaire and blood test may boost early detection rates to more than 80% and late-stage detection rates to more than 95%.
"The results are highly encouraging," Robyn Andersen, PhD, an associate member of the Public Health Sciences Division at the Hutchinson Center and lead author of the study, told Diagnostics & Imaging Week. "Cure rates for those diagnosed when the disease is confined to the ovary are approximately 70% to 90%. However, more than 70% of women with ovarian cancer are diagnosed with advanced-stage disease, when the survival rate is only 20% to 30%."
Andersen and other researchers administered the symptom questionnaire to 75 women about to undergo surgery for pelvic masses who were later diagnosed with ovarian cancer (the case group), and 254 healthy women at high risk for ovarian cancer due to a family history of the disease (the control, or comparison, group).
The cases were recruited through Pacific Gynecology Specialists at Swedish Medical Center (Seattle) and the controls were recruited through the Ovarian Cancer Early Detection Study, a joint project of the Hutchinson Center and the Marsha Rivkin Center for Ovarian Cancer Research (also Seattle).
Initially the questionnaire had 22 symptoms, which included fatigue. But the focus was significantly narrowed to four symptoms after many women with ovarian cancer reported exhibiting these four main symptoms the most.
"This research suggests that if a woman has one or more symptoms that are new for her, having begun within the past year, and if the symptoms happen nearly daily or at least 12 times a month, that may well be a signal to go in and discuss those symptoms with her doctor," Andersen said. "It's probably not going to be ovarian cancer, just as most breast lumps are not breast cancer, but it's still a sign that it might be worth checking with her doctor to see if a CA125 blood test and transvaginal ultrasound may be appropriate."
She stressed that just the CA125 blood test isn't very reliable for pre-cancer detection and to fill out the complete pre-cancer detection picture the questionnaire was needed.
CA-125, cancer antigen-125, is a protein that is found at levels in most ovarian cancer cells that are elevated compared to normal cells. CA-125 is produced on the surface of cells and is released in the blood stream.
The symptom-screening index was developed in 2006 by paper co-author Barbara Goff, MD, professor and director of gynecologic oncology at the University of Washington School of Medicine (Seattle).
Researchers are now looking toward a clinical study with 4,000 patients.
"If the results of this pilot study replicate in the clinical study, then we would look at a randomized trial," Andersen told D&IW. "If the findings were positive then ultimately this questionnaire coupled with the CA-125 test could become the standard testing procedure for identifying ovarian cancer in women."
She added, "In the immediate future the blood test and questionnaire could be used for patients with a high risk of ovarian cancer."
Assessing the symptoms included in the symptom-screening index may already be done by some doctors based on a consensus statement issued last year by the National Institutes of Health. The researchers hope their symptom index will help doctors know which among their patients who complain of symptoms such as abdominal swelling and pelvic pain might have cancer.
Ovarian cancer is the fifth-leading cause of cancer deaths in women, the leading cause of death from gynecological malignancy and the second-most-commonly-diagnosed gynecologic malignancy.
Because ovarian cancer is so hard to detect initially, it often isn't caught until months after it has moved into advanced stages, significantly reducing patient survival.
"And those months are months wasted for ovarian cancer treatments," Andersen said.