A new study has found that breast cancer can turn out to be more aggressive among obese women.
The study, led by Dr Massimo Cristofanilli, associate professor of medicine in the Department of Breast Medical Oncology at The University of Texas M.D. Anderson Cancer Centre, involved 606 women with locally advanced breast cancer. The researchers discovered that overweight women with breast cancer have aggressive disease with lower survival rates.
“The more obese a patient is, the more aggressive the disease. We are learning that the fat tissue may increase inflammation that leads to more aggressive disease,” said Cristofanilli.
The patients were sorted according to the body mass index in three groups. The first group included women who were normal/underweight with 24.9 or below BMI while the second had overweight with at least 25 but less than 30 BMI.
And the third group included women who were obese with BMI more than 30.
The five-year follow up revealed that the overall survival was 56.8 per cent among obese women, 56.3 per cent among overweight women and 67.4 per cent among normal weight women while the 10-year survival rate was 42.7 per cent among obese women, 41.8 per cent among overweight women and 56.5 per cent among normal weight women.
They also found that the rate of inflammatory breast cancer among obese women was 45 per cent compared with 30 per cent in overweight women and only 15 per cent in women considered normal weight.
The risk of breast cancer recurrence was also higher in obese or overweight women with 50.8 per cent of obese women reporting after 5 years and by 58 per cent reporting after 10 years.
Cristofanilli suggested that physicians have to pay close attention to breast cancer patients because commonly used drugs, such as tamoxifen, tend to increase weight gain during treatment.
The findings are published in the March 15 issue of Clinical Cancer Research , a journal of the American Association for Cancer Research.