By Emily Willingham
TUESDAY, Aug. 11, 2015 (HealthDay News) -- Ovarian cancer has a reputation as a swift killer that's often detected at a late stage, but a new study suggests that up to one-third of the women who are handed the grim diagnosis survive at least 10 years.
"We think that this is good information to communicate to women newly diagnosed with ovarian cancer," said study first author Rosemary Cress, an epidemiologist and associate adjunct professor in the department of public health sciences at the University of California, Davis. "Although ovarian cancer is a dangerous cancer, there is considerable variability and it is not always fatal."
For their study, published online recently in the Journal of Obstetrics and Gynecology, Cress and her co-authors looked at records for more than 11,000 women in California who had been diagnosed with a type of ovarian cancer between 1994 and 2001. They tracked survival information and other factors for this group up to 2011, comparing women who lived for 10 years or more with those who survived for shorter periods.
Factors associated with longer survival included younger age and having an early stage and low-grade tumor, the findings showed.
"Some of these factors are known to be inter-related," said Michael Bookman, medical gynecologic oncologist at Arizona Oncology and director of the gynecologic oncology research program at US Oncology Research. "For example, younger patients tend to have low-grade tumors."
Also affecting survival, he added, is how much cancer remains after the initial surgery. The new study, he said, "basically reinforces these points, emphasizing the importance of stage, age, tumor grade and tumor type."
But Cress and her colleagues were also surprised to discover that some women who lived longer had high-risk cancers. Of the nearly 3,600 long-term survivors, 954 would have been classified as being at high risk of an earlier death because of their older age or the advanced stage of their cancer.
"Older patients are more likely to have other chronic health conditions," Cress explained, and these conditions can affect how aggressively a patient can be treated.
The authors noted in their paper that longer survival following a cancer diagnosis carries its own set of issues for patients, including anxiety, fatigue and social problems.
Susan Chinn, of Honolulu, is an eight-year survivor diagnosed in November 2007 at age 35 with what she described as early stage ovarian cancer. She agreed that survival brings its own baggage.
Chinn knew at diagnosis that her five-year survival prospects were pretty good because her cancer was diagnosed at an early stage.
"After all was said and done, I was in a good place physically, [but] mentally, I was a wreck," she said. "Looking back, I wish there was monitoring to check the mental and emotional impact of a cancer diagnosis," which would have saved her months of battling a crushing depression, she said. She ultimately found relief with her local gynecological cancer support group Hui Malama O Ola, which she said "has been instrumental in my recovery."
The reasons for the unexpected 10-year survival rate are unclear. Cress pointed to the possibility of better surgical treatment and more targeted chemotherapy.
Study lead author Dr. Gary Leiserowitz, interim chair of the department of obstetrics and gynecology at UC Davis, said in a statement that one hypothesis is that carrying certain mutations might make a tumor more responsive to chemotherapy than a tumor that doesn't have these mutations.
Figuring out these factors is important. According to the U.S. Centers for Disease Control and Prevention, about 20,000 women receive an ovarian cancer diagnosis each year in the United States, and 90 percent of these women are over age 60. More than 14,000 women in the United States die of the disease annually.
The cancer is notorious for flying under the radar until its later stages, in part because its symptoms can be vague. They include abnormal vaginal bleeding, pressure or pain in the pelvic region, a change in bathroom habits, and feeling full quickly when you eat.
Bookman explained that more than 80 percent of women have advanced-stage disease when they are diagnosed. That statistic, he said, "reflects the tendency for ovarian cancer to spread at a very early stage without causing symptoms."