After surgical procedures, interventions to reduce postoperative bleeding are of great importance. In this study, the effect will be investigated of smearing tranexamic acid, which is designed for injection, directly onto the raw wound surface (topical application) created during surgery. Topical application allows a small amount of drug to reach a large wound area, higher drug concentration in the exposed wound surface but very low concentration in the body, and no risk of injury from needles. The researchers have recently shown that topically applicated tranexamic acid reduces bleeding in women who had two-sided breast reduction surgery. Now it will be studied whether topically applicated tranexamic acid reduces bleeding after breast surgery for breast cancer.

After surgery for breast cancer patients may also experience problems with long lasting seroma. Therefore it will at the same time be investigated whether topical tranexamic acid reduces the development of seroma in these patients.

Inclusion Criteria:

• breast cancer
• undergoing unilateral mastectomy with or without axillary node dissection
• received adequate oral and written information about the study and signed an informed-consent form

Exclusion Criteria:

• pregnant or breastfeeding
• known thromboembolic disease or with high risk of thromboembolism, warranting extra anticoagulation in connection with the procedure
• known allergy to tranexamic acid/Cyklokapron®