LOCAL-CONTROL FOLLOWING BREAST-CONSERVING SURGERY FOR INVASIVE CANCER- RESULTS OF CLINICAL-TRIALS

Prospective, randomized clinical trials have demonstrated that the alt ernatives of mastectomy or conservative surgery plus radiation therapy provide equivalent survival for patients with invasive breast cancer, The identification of a subset of women who could undergo conservativ e surgery without radiotherapy would avoid the costs, inconvenience, a nd complications of radiotherapy and is an important research goal, Fo ur randomized trials comparing conservative surgery alone with conserv ative surgery plus radiotherapy have demonstrated an average reduction in the risk of disease recurrence in the breast of 84% with the use o f radiotherapy, No significant differences in survival have been obser ved, although the available studies lack sufficient numbers of patient s to demonstrate a potential small, but clinically important, survival advantage for patients treated with radiotherapy, Subset analysis in the randomized trials and prospective studies of highly selected patie nts have failed to consistently identify a group of patients who do no t benefit from radiation therapy, Any recurrence of breast cancer is p sychologically devastating, and fewer than one half of the patients wh o have had disease recurrence after conservative surgery alone have un dergone further breast-conserving treatment, At present, a group of pa tients who do not require radiotherapy has not been reproducibly ident ified, and radiotherapy should remain a part of breast-conserving ther apy for invasive carcinoma.