Breast-Conserving Surgery and Radiation Treatment

Radiation is well known to have potent anti-tumoral effects. Experimental and clinical studies have repeatedly shown that radiotherapy can reduce both tumor burden and the risk of tumor recurrence in various circumstances, and has played an integral part in the conservative management of early breast cancer. In recent decades, extended surgery involving removal of the breast and often the surrounding muscle, has been progressively replaced with breast-conserving surgery (BCS) combined with radiation. Numerous studies have confirmed that BCS with radiation conferred equivalent survival while preserving the breast.
Unfortunately, radiation has unwanted effects. These can be mild and transient, such as skin redness, or late appearing and more severe, such as edema, fibrosis, carcinogenesis, or cardiac, vascular, or lung damage. Notwithstanding other reasons, such as prolonged treatment duration, additional costs, or access to facilities, it is natural that many researchers have investigated the issue of whether or not radiation could be omitted after BCS, and the Open Meta-Analysis - Breast-Conserving Surgery Project (OMB) has recently reviewed this [8]. Analyzing the results of 15 randomized clinical trials, the OMB found that patients who did not receive radiation experienced a three-fold increase in relative risk (RR) of recurrence in the operated breast, and an increase of 8.6% in the RR of all-cause mortality.
The present review explains the method used by the OMB, discusses the validity of the results, and examines the implications for current clinical practice.