RCR breast radiotherapy consensus guidelines

Producing the guidelines Draft radiotherapy guidelines Voted at consensus meeting at RCR March 2016 48 centres represented Agreed that a vote of 70% in favour would constitute a consensus Final guidelines currently out for comment

Cardiac sparing should be standard for all left sided breast tumours The heart should be excluded from the field All UK centres should have availability of breath holding techniques In left sided treatments (excluding IMC) the mean heart dose should be <2Gy in 90% of cases

Breast boost A boost should be considered for women under 50 years For women over 50 consider a boost if high risk features, especially grade 3 or extensive intraductal component Tumour bed clips should be standard of care Photon boost using IMRT/IGRT is recommended but electron or mini-tangent boosts are acceptable alternatives

Safe omission of radiotherapy Avoidance of radiotherapy should be considered in low risk tumours (T1 N0 G1-2 ER+ve HER2- ve) if willing to take minimum 5 years adjuvant endocrine therapy and mammographic followup to 10 years Discussion around appropriate age groups. Strongest support for >70 (and over 60 in study)

Internal mammary node irradiation Consider for patients with T4 disease or >4 axillary nodes Offer if 1-3 nodes and medial tumour Deliver using techniques that minimise heart and lung dose

Hypofractionation There is no indication for using more than 15 fractions for standard adjuvant breast, chest wall or axillary radiotherapy

Axillary radiotherapy in sentinel node positive disease Statement taken from recent ABS guidelines Isolated tumour cells/micro mets: no axilla treatment 1-2 macromets: no axilla treatment required if post menopausal T1 G1-2 ER+ve HER2-ve and having breast RT 3 or more nodes: further axilla treatment (AND or RT) Further treatment recommended if +ve node and mastectomy, T3, G3, ER-ve or HER2+ve No consensus reached on T2, premenopausal, LVI or extranodal spread Encourage POSNOC entry

Partial breast radiotherapy Can be considered if >50 years, G1-2, <3cm, N0, ER+ve, HER2-ve Can use external beam or multi-catheter brachytherapy 2mm minimum margins Exclude lobular cancers