Whole breast radiotherapy

Since the 1970s, there have been six randomized trials comparing breast-conserving therapy (lumpectomy followed by whole breast radiotherapy) to mastectomy for early-stage invasive breast cancer. Each study demonstrated no significant differences in disease-free survival or overall survival between the two treatments. Although no randomized trial of breast-conserving therapy vs. mastectomy has been performed specifically in patients with ductal carcinoma in situ (DCIS), a small percentage of the patients enrolled in the National Surgical Adjuvant Breast and Bowel Project B-06 trial were later found to have had DCIS, and in this subgroup, the overall survival rates were equivalent between the patients treated with breast-conserving therapy and those treated with total mastectomy. Several additional studies have demonstrated excellent survival rates with breast-conserving therapy in patients with DCIS, similar to rates previously reported in patients with DCIS treated with total mastectomy. Therefore, breast-conserving surgery followed by radiotherapy has become the treatment of choice for patients with stage 0, I, or II breast cancer (Tis, T1, T2). This chapter provides an overview of whole breast radiotherapy after lumpectomy for invasive breast cancer and DCIS.