Accelerated partial breast irradiation: more questions than answers ?
Ce dossier présente deux essais internationaux incluant respectivement 4 216 et 2 135 patientes (durées médianes de suivi : 10,2 et 8,2 ans) et évaluant, du point de vue de la récidive ipsilatérale et par rapport à une radiothérapie de l'ensemble du sein, l'efficacité ou la non infériorité d'une irradiation partielle accélérée du sein après une chirurgie conservatrice
Radiation therapy is applicable to around two-thirds of the more than 2 million people who are diagnosed with breast cancer annually worldwide.Traditionally, breast irradiation consisted of 25–33 separate treatment visits (or fractions) over 5–7 weeks, with treatment practice increasingly turning to hypofractionation consisting of 15–20 fractions over 3–4 weeks. Whole-breast irradiation has been the standard of care after breast conservation surgery, but accelerated partial breast irradiation (APBI) is becoming an attractive alternative. The observation that most local (within the breast) relapses occur in the region around the resected tumour bed led to the hypothesis that APBI to this region, with a safety margin of surrounding tissue, might reduce side-effects while maintaining the high rate of local control seen in patients treated with whole-breast irradiation. A second hypothesis was that overall treatment time could be safely reduced by using fewer fractions, thus minimising treatment burden for patients and health-care systems. Results of the RAPID 4 and NSABP B-39/RTOG 0413 5 randomised trials have been eagerly awaited, as they report outcomes in more than 6000 patients followed up for 8–10 years. So do these studies provide sufficient answers to the hypotheses on APBI ?
The Lancet , commentaire, 2018