S3 guidelines on breast cancer: locoregional treatment

In the updated S3 guidelines on “Diagnosis, therapy and follow-up of breast cancer”, locoregional therapy has been significantly revised due to new clinical study data. The focus of the updated version is on de-escalation of surgery on the breast and axilla in early stage breast cancer. The new definition of adequate resection margins requires “no ink on tumor” which will minimize the rate of re-excisions. Also, prophylactic mastectomy of the contralateral breast in patients without BRCA status or familial high-risk situation is still not indicated. Axillary lymph node dissection can be safely avoided in patients with 1–2 metastatic sentinel lymph nodes who undergo breast-conserving surgery with whole-breast radiotherapy. Major revisions have been made on the recommendations regarding a sentinel lymph node biopsy (SNLB) in patients with primary systemic therapy (PST). The SNLB after PST is now defined as the standard treatment in patients with initially clinically negative lymph nodes; however, a complete axillary dissection must be performed in initially lymph node positive patients regardless of the response to PST. Overall, the new recommendations of the S3 guidelines enable in many cases a de-escalation of surgical treatment and thus a reduction of morbidity. © 2018, Springer Verlag. All rights reserved.