In breast cancer patients treated by mastectomy and adjuvant post-mastectomy radiation therapy (PMRT) reconstruction is often delayed until 6 - 12 month after completion of chemotherapy and PMRT, due to high risk of complication. In this trial the safety of the delayed-immediate reconstruction method is tested, where a skin sparing mastectomy and reconstruction with silicone implant is performed at primary surgery to save the native skin for the final delayed reconstruction.

An increasing proportion of breast cancer patients treated by mastectomy wish for a breast reconstruction. If post-mastectomy radiation therapy is recommended, the reconstruction is often delayed until 6 - 12 months after completion of chemotherapy and radiation therapy due to risk of complication that might delay adjuvant treatment. At this time the native skin over the removed breast cannot be used in the reconstruction, resulting in a suboptimal aesthetic outcome. In the delayed-immediate reconstruction method, a skin sparing mastectomy and reconstruction with implant is performed at primary surgery, to save the native skin under radiation therapy, thereby improving the chance for a good aesthetic outcome at the final delayed reconstruction. In this trial breast cancer patients treated by mastectomy and loco-regional radiation therapy is randomized to either delayed reconstruction or delayed-immediate reconstruction. The complication rate as well as morbidity, aesthetic outcome and psychological well-being after delayed-immediate reconstruction will be compared with delayed reconstruction

Inclusion Criteria:

• Woman >18 years who are offered a mastectomy for invasive breast can-cer pT1-3, pN0-N3, M0 and wish reconstruction. The patient can be inclu-ded no matter the status of estrogen receptor, progesterone receptor, malignancy grade, and HER2 status.
• The patient is a candidate for loco-regional radiation therapy according to national or institutional guidelines.
• Highly selected patients with inflammatory breast cancer, namely those with complete or near complete response to neoadjuvant systemic thera-py judged by imaging and clinical examination before surgery. Any skin edema and clinical signs of skin involvement must have disappeared during systemic therapy. It is highly recommended that the decision to offer an inflammatory breast cancer patient inclusion in the DBCG RT Recon trial is made during a multidisciplinary team conference.
• Adjuvant systemic therapy with chemotherapy, endocrine therapy, anti-HER2 treatment and other targeted therapies used in the adjuvant setting either as new standard or as part of a trial during the course of the trial is accepted.
• Neoadjuvant chemotherapy and primary systemic therapy of an operable breast cancer is accepted.
• Patient with previous non-breast malignancy is accepted if the patient has been without disease minimum 5 years, and the treating oncologist esti-mates a low risk of recurrence. Patients with the following diseases can be accepted despite less than 5 years disease free interval: carcinoma in situ cervicis, carcinoma in situ coli, melanoma in situ, basal cell carcino-ma of the skin, squamous cell carcinoma of the skin.
• Life expectancy minimum 10 years.

Exclusion Criteria:

• Pregnant or lactating.
• Previous breast cancer or Ductal carcinoma in Situ (DCIS).
• Bilateral breast cancer.
• Previous radiation therapy to the chest region.
• Previous non-breast malignancy (not including carcinoma in situ of the cervix or colon, melanoma in situ, basal cell carcinoma of the skin, and squamous cell carcinoma of the skin) within 5 years.
• Conditions indicating that the patient cannot go through breast reconstruction, the radiation therapy or follow up.
• Not being able to participate due to language or other personal issues.
• Life expectancy less than 10 years.