A new study provides evidence that obesity leads to more aggressive types of ovarian cancer. Writing in the October 1, 2006 issue of CANCER (http://www.interscience.wiley.com/cancer-newsroom), a peer-reviewed journal of the American Cancer Society, researchers say they found significant differences in histological types of epithelial ovarian cancer depending on body mass index (BMI). In addition, for women with advanced disease, a higher BMI was associated with decreasing survival rates.
Increasing evidence points to the importance of being obese (BMI greater than 30) and overweight (BMI between 25 and 30) in the development and prognosis of several cancers, including breast, uterine and colorectal. Their relationship to ovarian cancer is less well understood.
Almost one in 60 women will develop ovarian cancer during their lifetimes. Most will be diagnosed with advanced disease and 70 percent will die in five years, making it one of the most lethal cancers. There are several types of ovarian cancer, but tumors that begin from surface cells of the ovary (epithelial cells) are the most common type. A few recent studies have shown that obese patients have a worse outcome. Scientists hypothesize that higher mortality associated with obesity may be caused by more aggressive tumors rather than delays in diagnosis.
Andrew J. Li, M.D. of the Cedars-Sinai Medical Center and Women's Cancer Research Institute at the Samuel Oschin Comprehensive Cancer Institute and colleagues reviewed data from 216 women with ovarian cancer to identify relationships between obesity, ovarian cancer, tumor biology, and outcome.
Comparison of obese (35 of 216) and ideal weight (108 of 216) women showed 29 percent of obese women and 10 percent of ideal weight women had localized disease. However, obesity was significantly associated with both different cellular characteristics of the tumor and outcome in women with advanced disease.
Obese women were more likely to have mucinous types of tumors and tended to have non-serous types as well.
Though increasing BMI was not associated with differences in treatment for women with advanced disease, a BMI greater than 25 was associated with shorter disease-free survival. In addition, increasing BMI was associated almost linearly increasing risk of mortality.
"This study supports the hypothesis that obesity impacts ovarian cancer mortality by influencing tumor biology," conclude the authors. Additionally, the researchers observed "significant differences in the risk of cancer progression and cancer-related mortality associated with increasing BMI in a fairly 'dose-dependent' fashion."
Article: "Effect of Obesity on Survival in Epithelial Ovarian Cancer," James C. Pavelka, Rebecca S. Brown, Beth Y. Karlan, Ilana Cass, Ronald S. Leuchter, Leo D. Lagasse, Andrew J. Li, CANCER; Published Online: August 28, 2006 (DOI: 10.1002/cncr.22194); Print Issue Date: October 1, 2006.
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