Obesity Raises Cervical Cancer Risk

July 14, 2003 -- Overweight women are at high risk of cervical cancer -- double the risk of other women, a new study suggests.

Excessive fat has been shown to increase levels of estrogen, leading to development of endometrial and cervical cancer -- specifically, a subtype of cancer called adenocarcinoma, writes lead researcher James V. Lacey Jr., PhD, an epidemiologist with the National Cancer Institute.

Height, weight, and obesity are risk factors for endometrial cancer. Since height and weight are also risk factors for cervical cancer, Lacey wanted to find out whether obesity could be a risk factor for cervical cancer, too.

His study appears in the August issue of the journal Cancer.

Adenocarcinoma cells are the most common type of cervical cancer cells, writes Lacey. Another type of cancer cell, squamous cell, can also develop on the cervix -- but it is not linked to estrogen levels.

In their study, Lacey and colleagues looked at a variety of risk factors in 560 women: 124 diagnosed with adenocarcinoma, 139 with squamous cell cancer, and 307 women who did not have cancer. The findings:

• Women who were heavier, had a higher body mass index (BMI) or had fat concentrated in their midsection were far more likely to have adenocarcinoma.
• Women with a BMI greater than 30 -- considered obese -- were twice as likely to be diagnosed with adenocarcinoma.
• Women with high waist-to-hip ratios (apple-shaped body) were also twice as likely to develop adenocarcinoma.
• Women with a higher BMI had adenocarcinoma that was more advanced at diagnosis, even if they were getting regular Pap smears.

In overweight and obese women, Pap smears may be less reliable in detecting early signs of adenocarcinoma and cervical cancer, he writes. Larger studies are needed to explore this possibility.