This study aims at providing first evidence that axillary clearance by using an operation technique including the precise LigaSure instrument and closure of dead space of the axilla will result in an operation were a drain is not necessary and the need for seroma evacuation after surgery is very limited.

Axillary clearance in breast cancer is usually performed by using a drain to prevent seroma formation and to support obliteration of the dead space in the axillary carry out. The hypothesis made in this protocol is that axillary clearance by using an operation technique including the use of the precise LigaSure instrument and closure of dead space can be done without using a postoperative drain.

The AND PRECISE PROTOCOL aims at providing first evidence that axillary clearance by using an operation technique including the precise LigaSure instrument and closure of dead space of the axilla will result in an operation were a drain is not necessary and the need for seroma evacuation after surgery is very limited Patients undergoing axillary clearance necessary for achieving reasonable control in invasive breast cancer and participating in the AND PRECISE protocol will undergo the operation by using a technique including the use of the precise LigaSure instrument and closure of dead space. Postoperatively, the numbers of seroma punctions and the amount of seroma will be recorded prospectively. Patients will be asked to record on a daily basis their experience of pain by a visual analog scale of pain.

The main study parameter is the percent of cases which successfully did not need seroma punctions after the intervention.

Potential disadvantages for the patient are risk for more seroma formation and discomfort. Patients will be asked to record on a daily basis their experience of pain by a visual analog scale of pain.

Inclusion Criteria:

• Indications for axillary clearance can be a tumor positive sentinel node or tumor positive lymph nodes proven by ultrasound or fine needle aspiration cytology.
• For this pilot, only patients undergoing breast conserving surgery are eligible.
• Axillary clearance can be performed after previous sentinel node procedure, at the same operation, and after neo-adjuvant chemo therapy, and as secondary procedure in case of axillary relapse after previous treatment for breast cancer.

Exclusion Criteria:

• Patients undergoing a modified radical mastectomy including an axillary clearance.
• Preoperative preexisting seroma.