Fredriksson M, Persson E, Dahlquist G, et al. - A small but significantly elevated risk of cancer exists in women with childhood-onset type 1 diabetes. Men do not have any such tendency. There is a lack of clarity on the reason behind this.

• This study included 18,724 persons (53% men) with childhood-onset type 1 diabetes, and four referents for each of them.

• Overall 135 different cancers, all diagnosed post-diabetes, occurred in 125 persons (61 % women) with diabetes.

• When the Swedish general population was used as referents for women with diabetes, the overall standardized incidence ratio (95%) was 1.28 (1.02, 1.58).

• Comparison of women with diabetes with matched referents yielded a hazard ratio of 1.42 (1.10, 1.85).

• No increased risk was observed for men.

• Most common malignancy type in women was breast cancer and in men it was testicular cancer.