Researches reported that obese women are less likely than thin females to be screened for breast and cervical cancers.
In a review of 32 previously published studies, researchers found that obesity was consistently linked to lower rates of breast and cervical cancer screening among white women. Fourteen studies focused on cervical cancer, 10 on breast cancer and 8 looked at colorectal cancer.
Sarah S. Cohen and colleagues at the University of North Carolina, Chapel Hill, report the findings in the online edition of the journal Cancer.
The National Cancer Institute recommends that women have a mammogram to detect breast cancer every one to two years, starting at age 40, and a Pap test to screen for cervical cancer at least once every three years, beginning about three years after they start having sex.
It's not certain why obese women are less likely to get these screening tests, as few studies have been designed to look at the underlying reasons, according to Cohen and her colleagues.
However, they point out, some research shows that obese women often worry about embarrassment in the exam room, negative reactions from healthcare providers and "lectures" about their weight. Obese women also often find gowns, exam tables and equipment at doctors' offices very inconvenient for them.
Another possibility, according to Cohen's team, is that doctors less often recommend cancer screening to obese women than to thinner women. But there was a lack of evidence supporting this in the studies reviewed. One study found that obese women were more likely to say their doctor had advised them to get a Pap test.
In contrast to the case with breast and ovarian cancer screening, Cohen's team found no consistent evidence that obesity lowered the odds of colon cancer screening.
About half of the studies on colon cancer screening found lower screening rates among obese women, while the rest did not.
The findings suggest that more should be done to encourage obese women, particularly obese white women, to get regular mammograms and Pap tests, according to Cohen and her colleagues.
With colon cancer screening, however, the number of women who follow recommended testing is too low across the board.
This, they write, means that "outreach to all women should remain the objective for colorectal cancer screening programs."
Colorectal cancer, also called colon cancer or large bowel cancer, includes cancerous growths in the colon, rectum and appendix. It is the third most common form of cancer and the second leading cause of cancer-related death in the Western world. Colorectal cancer causes 655,000 deaths worldwide per year. Many colorectal cancers are thought to arise from adenomatous polyps in the colon. These mushroom-like growths are usually benign, but some may develop into cancer over time. The majority of the time, the diagnosis of localized colon cancer is through colonoscopy. Therapy is usually through surgery, which in many cases is followed by chemotherapy.