Surgery of the primary tumor in metastatic breast cancer

Survival in patients with metastatic breast cancer is improving due to more sensitiveimaging modalities, resulting in an increased rate of diagnosis in asymptomaticpatients with a lower disease burden. Moreover, the improvements in systemic therapyhave prolonged the survival of patients with metastatic disease, including the subsetwith intact primary tumors.The role of surgery of the intact primary tumor on survival in patients with metastaticdisease is uncertain. It is now quite clear that local control does impact survival instage I to III breast cancer, and this is particularly evident in patients with positivenodes, a group traditionally considered to have systemic disease, and those at higherrisk of local relapse. If preventing local recurrence decreases the incidence of distantrelapse in earlier-stage disease, a natural extension of this argument is to considerwhether optimizing local control, by removal of the intact primary tumor, may benefitselected patients with metastatic disease.In the past, multiple retrospective studies suggested a survival benefit of the surgery ofthe primary tumor in stage IV patients, but several selection biases in all these studiesprohibit a definitive conclusion. Only randomized clinical trials could verify the truerole of the local surgery in metastatic disease. In the meantime, surgery seems to be aneffective means of maintaining local control on the chest wall during the patient’slifetime, especially in patients with limited metastatic disease who have a goodresponse to initial systemic therapy. Either mastectomy or lumpectomy areappropriate approaches when surgery is chosen. The data on axillary surgery areextremely limited, but if surgery is undertaken, removal of all gross disease seemsprudent. The benefit of radiation therapy following surgery is also uncertain, anddecisions regarding its use should be made on a case-by-case basis. It is mandatorythat all patients be fully informed about the uncertainties of this approach and not berushed into having a local surgical or radiotherapeutic treatment.