Omission of postoperative radiation after breast conserving surgery: A progressive paradigm shift towards precision medicine

Highlights • Post-operative radiotherapy is standard after breast conservation in early breast cancer. • To de-escalate the treatment burden, indentifying a subset at very low risk of relapse is crucial. • Clinical and pathological factors are important, but can be integrated with genomic signatures. • Ongoing trials will provide evidence on patients at low risk for radiotherapy omission.
Radiation therapy is a standard therapeutic option in the post-operative setting for early breast cancer patients after breast conserving surgery, providing a substantial benefit in reducing the risk of local relapse with a consequent survival gain. Nevertheless, the reduction in the burden related to treatment is becoming crucial in modern oncology for both local and systemic therapies and investigational efforts are being put forward by radiations oncologists to identify a subset of women at very low risk to be potentially omitted from post-operative irradiation after breast conservation. Clinical factors, classical pathological parameters and new predictive scores derived from gene expression and next generation sequencing techniques are being integrated in the quest toward a reliable low-risk profile for breast cancer patients. We herein provide a comprehensive overview on the topic.