13th Asia-Pacific Oncologists Annual Meeting
Pontifical Catholic University of Chile, Chile
Title: Surgical margins in breast conserving treatment for invasive and DCIS tumors
Biography: Mauricio Camus A
Introduction: Although breast conserving treatment (BCT) has been standard practice for more than 20 years, there was no
consensus on what constitutes an optimal negative margin width, until the last 2 years.
Objective: To review the Consensus Guidelines on Margins for BCT with whole-breast irradiation in DCIS and in Stages I and II invasive breast cancer.
Material & Methods: A multidisciplinary consensus panel used a meta-analysis of margin width and ipsilateral breast tumor recurrence (IBTR) from a systematic review of 33 studies including 28,162 patients for invasive breast cancer and a review of 20 studies including 7,883 patients for DCIS.
Results: Positive margins (ink on invasive carcinoma or ductal carcinoma in situ) are associated with a 2-fold increase in the risk of IBTR compared with negative margins. For invasive breast cancer, negative margins (no ink on tumor) optimize IBTR.
Wider margins widths do not significantly lower this risk. Th e routine practice to obtain wider negative margin widths than ink on tumoris not indicated. For DCIS, a 2-mm margin minimizes the risk of IBTR compared with smaller negative margins. More widely clear margins do not significantly decrease IBTR compared with 2-mm margins.
Conclusions: Th e use of no ink on tumor is the standard for an adequate margin in invasive cancer. A 2-mm margin is the standard for an adequate margin in DCIS. Clinical judgment should be used in determining the need for further surgery in DCIS patients with negative margins narrower than 2-mm. Both consensus guidelines have the potential to decrease reexcision
rates, improve cosmetic outcomes, and decrease health care costs.