Meta-analysis of long-term efficacy and safety of hypofractionated radiotherapy in the treatment of early breast cancer

Abstract

Purpose: To evaluate the efficacy and safety of hypofractionated radiotherapy in women with early stage breast cancer after breast conservative surgery.

Methods: We performed a search for randomized controlled trials (RCTs) that compare conventional fractioning and hypofractioned radiotherapy. The studied outcomes were local and loco-regional recurrence, disease-free survival, mortality, cardiac ischemia, rib fracture and pulmonary fibrosis up to 5 years and 5 years after treatment. Shrinkage of the breast, breast tightening, telangiectasia, breast edema, shoulder stiffness and arm edema were evaluated within 10 years. Cosmesis and acute skin radiation toxicity were evaluated.

Results: Ten publications of six RCTs were included. No statistical difference in local and loco-regional recurrence, disease-free survival, mortality, cardiac ischemia, ribs fracture and pulmonary fibrosis, shrinkage of the breast, breast tightening, shoulder stiffness, arm edema and cosmesis was found. However, there was a significant difference in favor of hypofractionated for breast edema (RR 0.68, 95% CI 0.53 to 0.88, p = 0.003, 4675 patients), telangiectasia (RR 0.41, 95% CI 0.19 a 0.87, p = 0.02, 5167 patients), and acute skin radiation toxicity (RR 0.34, 95% CI 0.19 to 0.61, p = 0.0003, 347 patients).

Conclusion: There is no difference between conventional fractionation and hypofractionated in terms of efficacy when we evaluate local recurrence, loco-regional recurrence, distance recurrence, disease-free survival and mortality. There is also no difference concerning safety when we assess the occurrence of fibrosis, ischemia and ribs fractures. Hypofractionated showed better results in relation to breast edema, telangiectasia, and acute skin radiation toxicity.

Keywords: Breast cancer; Breast-conserving surgery; Conventional fractionation; Hypofractionated radiotherapy.