Morbidly obese women are at incredible risk for multiple cancers, primarily breast and endometrial cancer but also colorectal and other gynecologic cancers, told Dr. Susan C. Modesitt from University of Virginia Health System, Charlottesville. I hope that physicians begin to be proactive in evaluating these women for cancer promptly when indicated.

Dr. Modesitt and team investigated the number and types of cancers in 1482 morbidly obese women who underwent bariatric surgery at the University of Virginia. These patients were compared with a control population of morbidly obese women who did not undergo surgery.

The study found that of all, 53 bariatric surgery patients (3.6%) developed invasive cancer, including 15 with breast cancer and 9 with endometrial cancer.

Overall, 34 women (64.1%) were diagnosed and treated before bariatric surgery, while 17 women (32%) were diagnosed after bariatric surgery.

Compared to control group, bariatric surgery patients with cancer were older at the time of surgery. However, there were no significant differences between the women with or without cancer.

Control women with morbid obesity who did not undergo bariatric surgery had a significantly higher cancer diagnosis rate (5.8% vs 3.6%) compared to the patients who had undergone bariatric surgery.

The researchers reported that obese women with cancer, regardless of bariatric surgery, were younger than the Virginia Cancer registry average age at diagnosis for virtually all cancers.

Although not conclusive, the authors explain, the fact that most of our women with bariatric surgery were diagnosed before their operation and the fact that fewer bariatric patients were diagnosed with cancer compared with their obese counterparts may lend support to the hypothesis that bariatric surgery could be protective for obesity-related cancers.

The hard part is knowing whether weight loss in these women will translate into a decrease in their risk for cancer, and we are trying to start to answer those questions by evaluating multiple factors (both hormonal and adipose related) both pre- and post-bariatric surgery, Dr. Modesitt said.

Unfortunately, diet and exercise have not proven very effective strategies for weight loss in this population, which has prompted the explosion in bariatric surgery.

We are currently evaluating prospectively the incidence of menstrual irregularities in bariatric surgery patients and hope to start soon evaluating endometrial tissue, blood and adipose tissue to correlate differences in women with and without cancer and with weight loss, Dr. Modesitt added.