Radiation therapy for young women with early breast cancer: Current state of the art

A diagnosis of breast cancer at a young age, defined per guidelines as 40 years, represents a challenging situation requiring additional attention by the treating physicians including radiation oncologists and surgeons involved in the local treatment of these tumors. The present review aims at providing updated evidence on the state of the art about the available techniques and indications for radiation therapy in patients with early breast cancer, specifically focusing on young women. In addition, future perspectives including the ongoing trials and the potential impact of combined approaches with systemic therapies (such as immunotherapy) are reviewed. Major conclusions from this overview are that young women affected by invasive breast cancer seem to receive the greatest benefit from the boost on the tumor bed. Most young patients affected by ductal carcinoma in situ should receive postoperative whole breast irradiation (WBI). When regional node irradiation is considered, young age should be considered as a high-risk factor. Partial breast irradiation is not suitable for young patients and should be recommended within the context of a clinical trial. Importantly, robust data have already supported the efficacy and safety of hypofractionated-WBI schedules that should now replace standard fractionated-WBI as gold standard for all patients irrespective of their age. Finally, organs-at-risk sparing systems as strategy for prevention of radiation-related long-term toxicities should be strongly considered for these patients. Considering the lack of inclusion of young patients in several published trials as well as in some of the ongoing ones, robust evidence to counsel young breast cancer patients on the optimal radiation therapy approach is still lacking. Further studies and ad hoc subgroup analyses in this specific patient population are strongly warranted.