Local relapse rates are falling after breast conserving surgery and systemic therapy for early breast cancer: can radiotherapy ever be safely withheld?

Rates of local tumour relapse after breast conservation treatment in women with early breast cancer are falling. Explanations for this decline are considered in this review including advances in breast cancer management and aging of the breast cancer population. Breast surgery has become more standardised following publication of practice guidelines and is mostly carried out by specialist surgeons. Systemic therapies (hormonal therapy and chemotherapy) are now more effective and are recommended to a higher proportion of patients than ever before. Radiotherapy techniques have also improved. The contributions of each factor are difficult to quantify precisely, but all are likely to be relevant. In order to identify a subgroup of women that might safely be spared radiotherapy, several factors are analysed, including the prognostic significance for local relapse of tumour characteristics (pathologic data, gene-expression profiles), patient characteristics and life expectancy (age and comorbidities).