Surgical treatment of breast cancer: one size does not fit all. Current standards and new developments

Breast cancer surgery has undergone significant improvements in recent years and is still in a process of continuous change. The article defines the current treatment standards for primary tumors and lymph node surgery and highlights new developments in this field. In addition to the therapeutic role, surgery of breast cancer is increasingly performed with a diagnostic intent. The aim of surgery of the primary breast tumor in upfront surgery as well as after primary systemic treatment is tumor removal with tumor-free resection margins (R0, no ink on tumor). Due to improved early detection and increasingly more effective systemic options the rate of impalpable lesions at surgery is steadily increasing. Therefore, new marking and localization procedures challenge the existing standard of traditional imaging-guided needle localization. The use of intraoperative ultrasound as well as new magnetic and electromagnetic radiofrequency-based markers and probe-guided removal of nonpalpable lesions play an important role. In the field of lymph node surgery there is a continuous de-escalation of the radicality of surgery. This also affects the upfront surgery where the omission of sentinel lymph node biopsy (SLNB) appears to be safe in some subsets of patients. After neoadjuvant chemotherapy axillary lymph node dissection is increasingly being replaced by new procedures, such as SLNB or targeted axillary dissection (TAD). The development of new localization techniques for lymph node surgery is also becoming of increasing importance. In view of the multimodal locoregional treatment concept, for modifications of surgical standards it is important to clearly define the accompanying target volumes for irradiation.