Optimising therapy and avoiding overtreatment in breast cancer

Mené sur 731 patientes ayant subi une chirurgie conservatrice pour un cancer du sein de stade précoce et âgées d'au moins 70 ans (durée médiane de suivi : 23,9 mois), cet essai randomisé multicentrique de phase III évalue la non-infériorité, du point de vue de la qualité de vie à 24 mois et du taux de récidive ipsilatérale à 5 ans, d'une radiothérapie par rapport à une thérapie endocrinienne

Résumé en anglais

More than 100 000 women older than 70 years are diagnosed with hormone receptor-positive, early-stage breast cancer each year in the USA. A large proportion are at low risk of disease recurrence, placing them at risk of overtreatment. Previously, standard-of-care adjuvant therapy following breast-conserving therapy was radiotherapy plus endocrine therapy for at least 5 years. Results from randomised trials called this approach into question, examining whether radiotherapy could be safely omitted following lumpectomy. For example, in the PRIME II and CALGB 9343 clinical trials for women older than 65 years or 70 years, respectively, with node-negative, hormone receptor-positive breast cancer, treatment with adjuvant endocrine therapy without radiotherapy led to a modest increase in local disease recurrence but had no effect on overall survival. Therefore, omission of radiotherapy is now considered an acceptable approach for the treatment of women older than 70 years with breast cancer at low risk of recurrence.