Radiotherapy De-Escalation in Younger Patients with Breast Cancer: Are We There Yet?

Area of Science:

• Oncology
• Radiation Oncology
• Breast Cancer Research

Background:

• Radiotherapy de-escalation is established for early breast cancer, but trials predominantly feature older patients.
• Younger women with breast cancer have less favorable characteristics and worse outcomes, yet are underrepresented in de-escalation studies.

Purpose of the Study:

• To systematically review the safety and implementation of radiotherapy de-escalation strategies in younger patients diagnosed with early breast cancer.

Main Methods:

• A PRISMA 2020-compliant literature search identified relevant studies on radiotherapy de-escalation in younger breast cancer patients.
• Epidemiological data, randomized trials, and clinical guidelines were reviewed, supplemented by information from ClinicalTrials.gov.

Main Results:

• Younger age correlates with aggressive tumor biology, higher nodal involvement, unfavorable subtypes, and poorer survival.
• Moderate hypofractionation (15-16 fractions) is supported by evidence and guidelines for all ages.
• Evidence for ultra-hypofractionation, partial breast irradiation, and radiotherapy omission is less robust in younger populations.

Conclusions:

• Radiotherapy de-escalation in younger breast cancer patients warrants a cautious approach.
• Moderate hypofractionation is a safe option, but aggressive de-escalation strategies lack sufficient evidence in women under 50.
• Prospective studies with adequate representation of younger patients are needed to define optimal de-escalation strategies.