Early-Stage Breast Cancer Radiotherapy

Abstract

Radiotherapy is part of breast cancer treatment. The addition of radiotherapy to breast-conserving surgery decreases the risk of local recurrence by half in insitu disease. In invasive disease, postmastectomy radiotherapy (PMRT) in patients with 4 or more lymph nodes with metastatic involvement is the standart of care. A recent meta-analysis provided more evidence for PMRT benefit in patients with 1–3 involved nodes. After lumpectomy, whole-breast radiotherapy is still considered the standard of care. A meta-analysis showed a statistically significant increase in in-breast control and a decrease in breast cancer-specific deaths. In addition, boost radiotherapy to the tumor bed after breast-conserving surgery was shown to decrease local failure from 10.2% to 6.2%; the largest benefit was observed in patients ≤40 years of age (local failure decreased from 23.9% to 13%). The results of accelerated partial-breast irradiation (APBI) in patients with low local recurrence risk are controversial. Two large randomized APBI trials showed higher in-breast recurrences in patients treated with APBI than in those treated with whole-breast radiotherapy. Hypofractionation is also an appropriate therapeutic option for most patients with early breast cancer with comparable long-term toxicity profiles. A disease-free survival benefit of regional lymphatic irradiation has been demonstrated in patients with high-risk features with no axillary nodal involvement.