Radiotherapy after breast-conservation surgery: how much is enough?

The National Surgical Adjuvant Breast Project (NSABP) clinical trials have demonstrated that breast conservation surgery (lumpectomy), axillary dissection, and breast irradiation for women with Stage I and II invasive breast carcinoma provide disease-free survival and overall survival rates equivalent to modified radical mastectomy. Breast irradiation following lumpectomy decreases the incidence of in-breast tumor recurrence compared to lumpectomy alone. The addition of adjuvant systemic therapy appears to further decrease the incidence of in-breast tumor recurrence. Irradiation of the internal mammary and supraclavicular nodal regions is not indicated for patients with Stage I and II carcinoma. Similarly, irradiation of the axilla after axillary dissection is not indicated.