Obesity Reduces Ovarian Cancer Survival
It may also boost risk for tumor recurrence, study finds
MONDAY, Aug. 28 --, 2006 (HealthDay News) -- Obese women with ovarian cancer typically fare worse than those who are not obese, a new study shows.
"If women develop ovarian cancer and they are obese, they have a lower chance of survival than those who are overweight or normal weight," noted senior researcher Dr. Andrew Li, a gynecologic oncologist at Cedars-Sinai Medical Center, in Los Angeles.
Obese women with advanced disease may also have a shorter time period to cancer recurrence, according to the study, which will be published in the Oct. 1 issue of Cancer.
Obesity is known to be a risk factor for several malignancies, including endometrial cancer and cancers of the kidney, breast and colon. Previous studies have also found that obesity bodes poorly for survival from ovarian cancer, said Li, who is also assistant professor-in-residence at the UCLA David Geffen School of Medicine.
Li said this study is the first to identify weight as an independent factor in the progression of ovarian cancer and survival. The study also provides a clue as to how obesity boosts the risk of death from ovarian cancer.
"I think fat cells secrete some kind of hormonal factor that actually makes cancer cells behave more aggressively and be less resistant to cell death by traditional chemotherapy drugs," he explained.
In the study, Li's team reviewed medical data from 216 women with ovarian cancer to evaluate relationships between obesity, ovarian cancer, the biology of the tumors and health outcomes. The women all had epithelial ovarian cancer, the most common kind, in which tumors originate from the surface cells of the ovary, called epithelial cells. The women had surgery for their cancer at Cedars-Sinai Medical Center between 1996 and 2003.
Eight percent of the patients were underweight, 50 percent were of ideal weight and 26 percent were overweight. Sixteen percent were obese, defined as a body mass index or BMI of 30 or higher.
Li and his team found that women with BMIs more than 25 (the beginning of the "overweight" range) had shorter disease-free survival times than did women with lower BMIs. And, as BMI increased, so did the chances of death from the cancer.
When the researchers evaluated all 216 patents, they did not find that overall survival differed much between the obese and the ideal body weight women. But, when they selected only those with stage III or IV (advanced) disease, a trend emerged. In these women, increased BMI became associated with both shorter time to cancer recurrence and shortened survival, the researchers said.
Li cautioned that, "These findings should certainly be validated in other trials." However, the study suggests that ovarian cancer survival can now be added to the list of reasons to maintain a healthy body weight, he said.
"This is an interesting paper," said Dr. Yoshiki Iwamoto, an assistant professor of surgical research at the City of Hope National Medical Center in Duarte, Calif. The results, he added, are consistent with what has been reported by others. "Not only ovarian cancer but [other cancers] have been shown to be associated with obesity," he said.
With more than 30 percent of U.S. adults obese, Iwamoto said, it's crucial for them to try to lower their weight.
Each year, about 20,000 U.S. women learn they have ovarian cancer, according to statistics from the American Cancer Society, and about 15,000 women die of the disease annually.
To learn more about ovarian cancer, visit the American Cancer Society.