Ovarian Cancer Often Announces Its Presence Through Symptoms
Ovarian Cancer Symptoms
Ovarian cancer is often thought of as a silent killer, coming to the attention of physicians only at its late stages when prognosis is poor. But according to a new study by UC Davis researchers, four in 10 women with ovarian cancer have symptoms that they tell their doctors about at least four months, and as long as one year, before they are diagnosed. The study will be published in the Oct. 1 issue of Cancer, a peer-reviewed journal of the American Cancer Society.
"Our findings suggest that ovarian cancer could be diagnosed earlier in some patients," said Lloyd Smith, professor and chair of obstetrics and gynecology at UC Davis School of Medicine and Medical Center and lead author of the study.
"The diagnosis is delayed in some patients because physicians order abdominal imaging or perform gastrointestinal procedures before they order a test more likely to diagnose ovarian cancer, such as pelvic imaging and/or CA-125 (a blood test that can detect ovarian cancer)."
Smith and his colleagues compared diagnosis codes and claims for diagnostic procedures for 1,985 elderly women with ovarian cancer, 6,024 elderly women with localized breast cancer, and 10,941 age-matched Medicare-enrolled women without cancer.
They found that patients with ovarian cancer were more likely than women in the other two groups to have seen their physicians for four symptoms: abdominal pain, abdominal swelling, gastrointestinal symptoms and pelvic pain. Overall, about 40 percent of women with ovarian cancer had physician claims indicating one or more visits for these symptoms four months or more before the cancer was diagnosed.
The UC Davis researchers also found that only 25 percent of the ovarian cancer patients who reported symptoms four or more months before diagnosis had diagnostic pelvic imaging or CA-125 blood tests. Most of the ovarian cancer patients who reported early symptoms received abdominal imaging or diagnostic gastrointestinal studies, which are less likely to detect ovarian cancer.
Within three months of their diagnosis, however, 54 percent of the ovarian cancer patients received pelvic imaging or CA-125 testing.
CA-125, short for cancer antigen-125, is a protein found at elevated levels in most ovarian cancer cells and released into the bloodstream. However, the CA-125 test returns a true positive result for only about half of early, Stage I ovarian cancers and therefore is not an adequate early detection tool when used alone.
For patients with later, Stage II, III or IV disease, the test has an 80-percent chance of returning true positive results. The remaining 20 percent of later-stage ovarian cancer patients do not show any increase in CA-125 concentrations.