Breast: Post-mastectomy radiotherapy

Why D is correct

This patient has three positive nodes with macrometastases (pT2N1). Post-mastectomy radiotherapy reduces locoregional recurrence in one-to-three node-positive disease (EBCTCG meta-analysis) and NICE NG101 supports offering it. However, the SUPREMO trial randomised exactly this intermediate-risk group (one to three involved nodes) to chest-wall radiotherapy or none, and its role in patients with one to three involved nodes is controversial — chest-wall symptoms are modestly increased and survival results are awaited. Current UK practice is therefore an individualised, shared decision at the multidisciplinary team rather than automatic radiotherapy, which is why it should be considered and discussed with the patient rather than simply offered to all.

And why the others are not

• AIncorrect. Although involved margins are an indication, macrometastatic node-positive disease alone is sufficient to recommend radiotherapy here.
• BIncorrect. Node-positive disease with macrometastases is a clear indication for post-mastectomy radiotherapy; mastectomy alone is insufficient.
• CIncorrect. Deferring radiotherapy forgoes the proven reduction in locoregional recurrence and breast cancer mortality.
• EIncorrect. Chest-wall radiotherapy is the core of post-mastectomy treatment; internal mammary chain alone would not address the chest wall.

Source NICE NG101 - Early and locally advanced breast cancer: diagnosis and management — National Institute for Health and Care Excellence. Early and locally advanced breast cancer: diagnosis and management. NICE guideline NG101. Published 18 July 2018, updated 2023.