Open Access

Toralf Reimer, Thorsten Kuehn, Volkmar Mueller, Nina Ditsch, Tanja Fehm, Ute-Susann Albert, Rupert Bartsch, Ingo Bauerfeind, Vesna Bjelic-Radisic, Jens-Uwe Blohmer, Wilfried Budach, Peter Dall, Eva Maria Fallenberg, Peter A. Fasching, Michael Friedrich, Bernd Gerber, Oleg Gluz, Nadia Harbeck, Andreas Hartkopf, Joerg Heil, Juliane Hoerner-Rieber, Jens Huober, Wolfgang Janni, Hans-Heinrich Kreipe, David Krug, Sherko Kuemmel, Sibylle Loibl, Diana Lueftner, Michael Patrick Lux, Nicolai Maass, Christoph Mundhenke, Tjoung-Won Park-Simon, Mattea Reinisch, Kerstin Rhiem, Achim Rody, Marcus Schmidt, Andreas Schneeweiss, Florian Schuetz, Hans-Peter Sinn, Christine Solbach, Erich-Franz Solomayer, Elmar Stickeler, Christoph Thomssen, Michael Untch, Marion van Mackelenbergh, Isabell Witzel, Achim Woeckel, Rachel Wuerstlein, Maggie Banys-Paluchowski, Marc Thill

• The German Guideline Commission (AGO: Working Group on Gynecologic Cancers) updated its recommendations on the diagnosis and treatment of breast cancer in March 2025. Chapters on oncological and oncoplastic-reconstructive surgery are coordinated with the Working Group for Plastic, Aesthetic, and Reconstructive Surgery in Gynecology (AWOgyn). The most important changes include the incorporation of INSEMA and SOUND trial results into the guidelines. In patients with low-risk characteristics, defined as age ≥50 years, postmenopausal status, hormone receptor-positive/HER2-negative subtype, tumor grading G1-2 with a maximum preoperative size of 2 cm, and unsuspicious axillary ultrasound and clinical examination, the sentinel lymph node biopsy (SLNB) can be omitted if breast-conserving surgery and whole-breast irradiation are planned. In patients with 1–2 macrometastatic sentinel lymph nodes (SLNs) undergoing a mastectomy and postoperative irradiation, completion axillary lymph nodeThe German Guideline Commission (AGO: Working Group on Gynecologic Cancers) updated its recommendations on the diagnosis and treatment of breast cancer in March 2025. Chapters on oncological and oncoplastic-reconstructive surgery are coordinated with the Working Group for Plastic, Aesthetic, and Reconstructive Surgery in Gynecology (AWOgyn). The most important changes include the incorporation of INSEMA and SOUND trial results into the guidelines. In patients with low-risk characteristics, defined as age ≥50 years, postmenopausal status, hormone receptor-positive/HER2-negative subtype, tumor grading G1-2 with a maximum preoperative size of 2 cm, and unsuspicious axillary ultrasound and clinical examination, the sentinel lymph node biopsy (SLNB) can be omitted if breast-conserving surgery and whole-breast irradiation are planned. In patients with 1–2 macrometastatic sentinel lymph nodes (SLNs) undergoing a mastectomy and postoperative irradiation, completion axillary lymph node dissection (ALND) is no longer recommended. After neoadjuvant systemic therapy (NST), ALND is recommended if the targeted axillary dissection (TAD) shows macrometastases in the sentinel and/or in the target lymph node (the node that was marked and had a macrometastasis in the biopsy before NST). Patients with isolated tumor cells in the sentinel and/or target lymph node should not receive ALND after NST. In case of ypN1mi status, the decision to perform a completion ALND should be made on a case-by-case basis. Oncoplastic surgery is safe and may replace a mastectomy in select cases.…