[Practice evolution of hypofractionation in breast radiation therapy and medical impact]

Whole breast irradiation after conservative surgery is the standard treatment for invasive breast cancer. Randomized studies indicate that hypofractionation can be equivalent for selected patients. This study focuses on fractionation practice evolution in a single centre, and analyses the economic impact of practice modification.

All prescriptions for invasive breast cancer between January 2010 and June 2014 were analyzed. Female patients 60 years or older, pN0 were considered for the economic study. Patients included in clinical trials or patient with high-grade tumours were excluded from the hypofractionation practice study, because physician could not choose fractionation. We used data from the Medical public health system to calculate cost per fraction and transportation cost.

Two thousand thirty one patients were treated; 399 were eligible for the economic study (20%) and 282 for the practice study (14%). Treatment with 25 fractions decreased from 90% to 16% in the first half of 2014. Meanwhile, treatment with 15 or 16 fractions increased from 6% in 2010 to 68% in the first half of 2014. Hypofractionated treatment proportion was 100% with 42.5Gy in 16 fractions in 2010 and 100% 40Gy in 15 fractions in 2014, according to long-term follow-up publication of START trials. Treatment with five fractions remained stable around 7% (4 to 16%), reserved for patients over 80 years (P<0.0001). Based on data from 3451 fractions in 2013, transport cost was calculated at 62 € per fraction, in addition to a 170.77 € reimbursement per fraction, giving a cost per fraction of 232.77 €.

Practice change led to an increase of hypofractionation in recent years. Hypofractionation may be currently prescribed and may concern 20% of patients. This practice evolution is beneficial for patients and the public health system.