HER2-positive and Triple-negative are subtypes of breast cancer more sensitive to systemic therapies, where the complete pathological response rate may be higher than 50%. This gave rise to doubts about the usefulness of traditional local treatments for such responders. Omission of surgery after vacuum assisted breast biopsy (VABB) as well omission of radiotherapy after conservative surgery would now seem to be reasonable alternatives to standard care for highly selected patients, in whom systemic treatments have provided the maximum response.
Women ≥ 18y.
Initial diagnosis of unifocal HER2-positive (regardless of HR status) or Triple-negative (HR positivity lower than 10% is allowed) T1-2, N0-1, M0 breast cancer.
Treated with neoadjuvant systemic treatment according to the center recommendations.
Maximum responders and/or complete pathological response proved by surgery.
One of the inclusion criteria missed.
Residual ductal carcinoma in situ (DCIS) at VABB and/or surgery.
Bilateral synchronous breast cancer.
Previous malignancy within 5 years.