Selective use of post-mastectomy flap irradiation in high-risk breast cancer patients.

The incidence of local recurrence after mastectomy can be reduced by chest wall radiotherapy. However, only a minority of patients are at substantial risk. No UK national guidelines exist for the use of mastectomy flap radiotherapy. This study evaluated a protocol, whereby only high-risk patients were treated with post-mastectomy flap radiotherapy; identified histologically by grade, vascular invasion and nodal status. All women treated by simple mastectomy for invasive breast cancer at the Nottingham Breast Unit from January 1993 to December 1995 were studied (n=292). Postoperative flap radiotherapy was given to 147 high-risk women (50.3%). Median follow-up was 76 months. Overall, 12 women (4.1%) developed a chest wall recurrence; six were single spot recurrences and the remaining six were either multiple spot (n=3) or field change (field change dermal invasion, n=3). The chest wall recurrence rate was 2.7% in those treated with radiotherapy. A low rate of local recurrence has been achieved with selective use of mastectomy flap radiotherapy.