Postmastectomy Breast Reconstruction in Patients with Non-Metastatic Breast Cancer

Guideline Objective

The objective of this work is to provide guidance on identifying which patients with breast cancer who are undergoing mastectomy are candidates for reconstruction, use of nipple-sparing mastectomy (NSM), the best timing of reconstruction (immediate or delayed), whether radiotherapy (RT) should influence timing, the choice between prepectoral versus subpectoral implants, and use of acellular dermal matrix (ADM) and autologous fat grafting as part of the reconstruction process. For this document, “reconstruction” refers to immediate or delayed reconstruction of the breast mound, not including aesthetic flat closure.

Patient Population

Patients diagnosed with non-metastatic breast cancer who will undergo therapeutic mastectomy and are considering or decided on reconstructive surgery. For purposes of this document, reconstruction includes both immediate and delayed reconstruction with implants and/or autologous tissue but does not include aesthetic flat closure.

Intended Guideline Users

1. Surgeons (general surgeons, surgical oncologists, plastic surgeons), radiation oncologists, and other clinicians involved in conducting mastectomies or in post-mastectomy reconstruction and adjuvant treatment.
2. Members of the Breast Cancer Advisory Committee, Ontario Health (Cancer Care Ontario), and others involved in the review and update of the Breast Cancer Pathway Map.

Research Question(s)

1. What is the effect of patient factors (smoking status, body mass index, breast size, age), comorbidities (diabetes, hypertension), or oncologic factors (previous breast surgery, previous radiotherapy (RT) to the breast/chest, inflammatory breast cancer, skin involvement) on post-mastectomy breast reconstruction outcomes?
2. a) In patients with breast cancer undergoing therapeutic mastectomy, is there a difference in outcomes in immediate versus delayed reconstruction for patients who do not receive RT?
   b) In patients with breast cancer undergoing therapeutic mastectomy, is there a difference in outcomes in immediate versus delayed reconstruction for patients who receive RT?
3. a) In patients with breast cancer who are candidates for SSM/NSM and reconstruction, is there a difference in outcomes between NSM and SSM?
   b) In patients with breast cancer, do oncologic outcomes for NSM vary according to the criteria used in selecting patients for NSM (e.g., tumour to nipple distance) or how nipple/areolar involvement is assessed (e.g., clinical examination, mammography, MRI, other imaging, biopsy of areola/nipple/nipple core, frozen/intraoperative or permanent section)?
   c) In patients with breast cancer and NSM, what surgical factors have been reported that influence
4. Does the use of prepectoral implants for postmastectomy breast construction result in differences in outcomes than subpectoral implants?
5. After therapeutic mastectomy, do outcomes differ for breast reconstruction using human-derived ADM, synthetic absorbable matrix, or no scaffolding/matrix? Are there differences in outcomes between different human ADMs or different synthetic absorbable matrices?
6. What are the benefits and risks of autologous fat grafting (lipofilling) as an adjunct to breast reconstruction?