Margin width and radiotherapy decision grid in DCIS
| Margin status | Radiotherapy use | Clinical interpretation |
|---|---|---|
| ≥ 2 mm | Yes | Optimal balance between local control and cosmetic outcome |
| > 2 mm | Yes | No evidence that wider margins further reduce recurrence risk |
| < 2 mm | Yes | Re-excision may be considered based on extent of disease, imaging findings, and surgical feasibility |
| Any margin | No | Higher risk of ipsilateral breast events; careful patient selection required |