In addition to reducing the risk of breast cancer recurrence, post-lumpectomy radiation therapy improves survival among women with early breast cancer. These results—from a combined analysis of 17 previous studies—were published in The Lancet.
Surgery for early-stage breast cancer may consist of mastectomy or lumpectomy. A mastectomy involves removal of the entire breast, whereas a lumpectomy involves removal of the cancer and some surrounding tissue. A lumpectomy is usually followed by radiation therapy in order to reduce the risk of cancer recurrence in or near the breast. The combination of lumpectomy and radiation therapy is referred to as breast-conserving therapy.
Several previous studies have reported giving radiation therapy after lumpectomy results in a lower risk of breast cancer recurrence than lumpectomy alone. To further evaluate the benefits of post-lumpectomy radiation therapy, researchers conducted a combined analysis of 17 previous studies. These studies included more than 10,000 women with early-stage breast cancer.
- Post-lumpectomy radiation therapy reduced the 10-year risk of breast cancer recurrence from 35% to 19%.
- The 15-year risk of death from breast cancer was 25% among women who did not receive post-lumpectomy radiation therapy and 21% among women who did receive radiation therapy.
- For every four breast cancer recurrences that were prevented by radiation therapy by year 10, one breast cancer death was prevented by year 15.
- Benefits of radiation therapy were seen in women with node-negative breast cancer as well as women with node-positive breast cancer.
These results provide additional evidence that giving radiation therapy after a lumpectomy substantially reduces the risk of cancer recurrence and also reduces the risk of death from breast cancer.
Reference: Early Breast Cancer Trialists’ Collaborative Group. Effect of radiotherapy after breast-conserving surgery on 10-year recurrence and 15-year breast cancer death: meta-analysis of individual patient data for 10,801 women in 17 randomised trials. Lancet. Early online publication October 20, 2011.