Medical and surgical postoperative complications after breast conservation versus mastectomy in older women with breast cancer: Swedish population-based register study of 34 139 women.

In breast cancer, either a bit of the breast or the whole breast is removed. Older women more often have their whole breast removed. Such larger surgery may have a higher risk of complications. Complications after surgery can lower the chances of survival. The aim of this project was to find out whether older age comes with more complications after breast surgery. The authors also wanted to know whether this has an effect on survival. This work used information on women aged 50 years and older operated on for breast cancer in Sweden from 2008 to 2017. Major surgical and medical complications after breast surgery were compared in three different age groups. In addition, death of any cause was analysed. Of 34 139 women, 8372 were 70­79 years old and 3928 were aged 80 years or older. These older women were compared to 21 839 women who were 50­69 years old. Major surgical complications did not increase with age. However, medical complications were more common in older women. Removing the whole breast gave more complications than removing only part of the breast. In women aged 80 years or older who had their whole breast removed, complications after surgery increased the risk of death. This was true even when considering how severe the cancer was, how it was treated, and also what kind of socio-economic background and afflictions other than breast cancer the women had. Therefore, removal of the whole breast should be done with caution in older women.