Contemporary treatment of ductal carcinoma in situ of the breast

Abstract

The main controversies surrounding the management of DCIS evolve around the need for adjuvant radiotherapy (RT) after adequate local excision (LE) of localized lesions and the role of adjuvant endocrine therapy. All randomized controlled trials (RCTs) examining the role of adjuvant RT and tamoxifen after LE were reviewed. The review also included important retrospective studies examining the treatment options for DCIS. All three RCTs demonstrated that adjuvant RT significantly reduced the incidence of ipsilateral breast tumour recurrence (IBTR) after 'adequate' LE of localised DCIS. Retrospective studies showed that the most significant effect for RT in DCIS was in women with high grade disease, with necrosis, large lesions and/or close margins. Total mastectomy is associated with the lowest rates of IBTR, but there is no evidence that it is superior to LE in terms of overall survival. Tamoxifen may be used in very selected patients with hormone sensitive (ER+) disease when the benefits outweigh the potential risks. Total mastectomy remains the treatment of choice for multicenteric and/or extensive disease. RT significantly reduces the risk of recurrence after adequate LE of localized DCIS. Radiation may be safely omitted after breast-conserving surgery (BCS) in postmenopausal women with low risk DCIS (USC/VNPI score =4-5). Tamoxifen can be considered in high-risk young women (USC/VNPI score =9-12) treated by BCS for ER+ DCIS as long as the potential benefits and adverse effects are explained to the patient.