The purpose of this study is to determine if autologous fat transplantation as a pre-treatment gives better results in breast reconstruction with implants after mastectomy and radiotherapy. One group is randomized to conventional reconstruction with implant and one to pre-treatment prior reconstruction with implant.

Our aims are:

1. To study whether lipofilling can decrease the number of reoperations and complications such as postoperative infections or not.
2. Evaluate the aesthetic results and the patients' experiences. For both these aims the hypothesis is that pre-treatment is in favour for the outcomes.

All patients will undergo breast reconstruction with expander implant. Half of the patients will be randomized to pre-treatment with lipofilling before the reconstruction. The randomization will be carried out with block randomization. A certain person that has not met the patients has been assigned to do this.

Fat transplantation: The fat will be harvested manually with dry technique using a Coleman cannula on a 10 ml syringe. There after the syringes and fat are centrifuged at 3000 rpm for 3 minutes. Liquid fat from lysed cells and blood will be separated from the purified fat cells and discarded. The fat graft will then be injected fan-shaped in multiple layers into the subcutaneous tissues of the breast using another blunt cannula with a diameter of 1.29 mm. If necessary to obtain a volume of 100 ml fat injected the procedure will be repeated. All sessions will be performed under general anesthesia in day surgery. Three month later the patients will undergo breast reconstruction with expander prosthesis.

Those patients that are randomized to not undergo pre-treatment will undergo breast reconstruction with expander prosthesis immediately.

After the reconstruction all patients will have as many appointments as necessary for expansion with a breast nurse at our clinic. If necessary the patient will also meet the surgeon. After the month the patients have a routine doctors appointment. After 6, 12 and 24 month the patients will be followed up with objective measurements of breast symmetry and they will fill in quality of life formularies. In this study we are using the validated formulary called Breast Q and a study specific formulary. At 24 month standardized photos of the breasts will be taken.

Inclusion Criteria:

• Previously undergone mastectomy and adjuvant radiotherapy.
• Will undergo breast reconstruction with expander prosthesis.
• Mammogram and ultrasound performed maximum three month prior surgery.
• At least one year since last operation or radiotherapy.

Exclusion Criteria:

• Known breast cancer relapse
• Distant metastases except axillary
• Any contraindication for anaesthesia
• Systemic disease such as diabetes mellitus type I.
• BMI >30 (if the patients lose weight they are eligible)