Factors contributing to improved local control after mastectomy in patients with breast cancer aged 40 years or younger.

Long-term local control rates were studied in a series of 659 patients with invasive breast cancer aged 40 years or younger, who underwent mastectomy in general hospitals in the southern part of the Netherlands between 1988 and 2005. During a median follow-up time of 6.0 years, 34 patients developed a local recurrence in the chest wall without previous or simultaneous evidence of distant disease. The 5- and 10-year actuarial local recurrence rates for the total group were 5.6% (95% confidence interval [95% CI], 3.5-7.7%) and 7.3% (95% CI, 4.7-9.9%), respectively. A multivariate analysis showed that patients receiving radiotherapy (hazards ratio [HR], 0.29; 95% CI, 0.10-0.96) or adjuvant systemic treatment (HR 0.23; 95% CI, 0.08-0.65) had a significantly lower risk of local recurrence. It is concluded that excellent local control rates can be obtained with mastectomy in young women with breast cancer, especially in those who receive adjuvant systemic treatment and/or radiotherapy.