While recent research suggests that having diabetes increases the risk of developing breast cancer, another new study shows that the use of insulin to control blood glucose levels may not be a factor.
A study released last month by Dr. Kirstin De Bruijn, a PhD student in the Surgery Department at the Erasmus University Medical Center in Rotterdam, Netherlands, and colleagues analyzed data from numerous global studies and found that those with diabetes had a 23 percent higher chance of developing breast cancer and a 38 percent increased risk of dying from the disease.
The research was released at the 2013 European Cancer Congress in September.
The use of various types of insulin, though, may not play a role, according to another recent study, released this summer in the journal Diabetes Care.
French researchers found that women with diabetes who use certain insulins to control their blood glucose levels do not have a higher risk of developing breast cancer.
In a study of 775 cases of breast cancer in women with diabetes compared to a 3,050-person matched control group, there was shown to be no association between the cancer and the use of a range of insulins including glargine, esparto, lispro, and human insulin.
Led by Dr. Lamiea Grimaldi-Bensouda of LA-SER of the National Conservatory of Arts and Crafts in Paris and colleagues, the study examined short- to mid-term duration of use of the insulins – an average of 3.2 years – and found that the odds ratio of developing breast cancer was 1.04 for those using glargine, 1.23 for lispro, 0.95 for aspart, and 0.81 for human insulin, compared to 1.0 for those with breast cancer who did not use insulin. Insulin dosage, duration of use, and tumor stage did not impact the results, researchers said.
“This international study found no difference in the risk of developing breast cancer in patients with diabetes among the different types of insulin with short- to mid-term duration of use,” Grimaldi-Bensouda said.
The Rotterdam study was based on the results of 20 trials that took place between 2007 and 2012 and included more than 1.9 million patients.