Obesity might lead to more aggressive ovarian cancer

Obesity might cause an increase in deaths related to ovarian cancer, according to a study published in the Aug. 28 edition of the journal Cancer, the New York Times reports.

Andrew Li, assistant ob-gyn professor of obstetrics and gynecology at the University of California-Los Angeles, and colleagues reviewed the medical records -- which included information about the women's age, height, weight and chronic conditions -- of 216 women who underwent surgery for epithelial ovarian cancer at Cedars-Sinai Medical Center in Los Angeles to determine whether excess fat had a direct effect on tumor growth (Bakalar, New York Times, 8/29). Thirty-five of the women were considered obese, which was defined as having a body mass index of 30 and greater, and half of the women had an ideal BMI (BBC News, 8/28). Women with BMIs of between 18.5 and 25.0 were defined as having an ideal BMI, according to the study (Pavelka et al., Cancer, 8/28).

Study Findings

The study finds that women who are considered obese and living with ovarian cancer have a lower survival rate; that the recurrence of the cancer is sooner than expected; and that they risk an earlier death, compared with women who have an ideal BMI (Boseley, Guardian, 8/29). According to the researchers, the findings are not definitive because the sample population was small and because the researchers used a study method that entailed using data from previous studies. In addition, the findings might not be definite because obese women might receive a lower dose of chemotherapy than nonobese women in relation to their body surface, which could allow the tumor to grow in those women; fluid in the body cavity might have artificially increased the BMI of some women; and other conditions, such as hypertension and diabetes, which are more common among obese women, could have affected the obese participants' survival rates. However, the researchers said that it is unlikely the variables caused the lower survival rate of the women and that the additional fat tissue in overweight and obese women is more likely the cause of the additional risk of death (New York Times, 8/29). "While further molecular studies are warranted, our study suggests that fat tissue excretes a hormone or protein that causes ovarian cancer cells to grow more aggressively," Li said, adding, "The next steps will be to examine this relationship more closely and to determine the exact biological mechanisms that influence tumor growth in ovarian cancer" (Guardian, 8/29).