We propose to conduct a multicenter prospective RCT in Switzerland to evaluate the impact of TachoSil® on axillary drainage after ALND for breast cancer. We hypothesize that the use of TachoSil® significantly and relevantly reduces the volume and duration of axillary drainage after ALND. This has the potential to increase patients' quality of life, as well as to shorten the length of hospital stay and reduce hospital costs, and provides the rationale and the clinical relevance for the proposed RCT. If the proposed RCT shows a minimum of 33% relative drainage reduction, a follow-up trial is justified. The follow-up trial will be conducted with all patients receiving TachoSil® and randomization with versus without axillary drainage. Therefore, the final goal is the omission of axillary drainage after ALND in the future.