Prepectoral Implants and Radiation Therapy

Breast cancer is the most common cancer in women worldwide. It is usually diagnosed at the non-metastatic stage, but up to 30% of women with early breast cancer diagnosis eventually develop metastatic disease in the future [1]. Breast cancer treatment is multidisciplinary, involving surgery, systemic therapy, and radiation therapy (RT), where the most appropriate treatment-sequencing is planned individually [2]. Following the Milan, NSABP, Danish breast Cancer Group, and EORTC trials, patients with early breast cancer were mostly treated with breast-conserving surgery (BCS) and whole breast irradiation (i.e., breast-conserving therapy, BCT). These trials demonstrated an equivalent or a non-inferiority result for BCT compared to mastectomy [3-7]. In 1990, the panel of the National Institutes of Health (NIH) Consensus Development Conference on Treatment of Early-Stage Breast Cancer released a statement that BCT is preferable to total mastectomy because it provides survival equivalence while preserving the breast [8]. A later study even demonstrated that BCT is not just inferior to mastectomy in early-stage breast cancer but may even lead to improved 10-years overall and relative survival compared with mastectomy. These results were suggested to be related to postoperative radiation in the case of BCT, thereby treating subclinical disease by radiation [9]. Nevertheless, a decade after the NIH statement, publications show a trend in the treatment of early-stage breast cancer patients, indicating that more than a third of the patients with early breast cancer who are eligible for breast conservation opt for mastectomy as their primary surgical procedure [10-13].