The need for clear margins is paramount, in successful breast conserving therapy. What is a margin, and, what constitutes a clear margin has been the topic of conversation/debate for years.
So, what is the significance of a positive margin? Positive margins (tumor cells seen directly on the edge of the surgical specimen) are associated with a two-fold increase in the risk of local recurrence (IBTR – Ipsilateral Breast Tumor Recurrence) compared with negative margins. There is now a universal consensus (Society of Surgical Oncology and the American Society for Radiation Oncology) that ‘no tumor on ink’ – no tumor to the edge of the surgical specimen, is associated with low rates of IBTR and has the potential to decrease re-excision rates, improve cosmetic outcomes, and, decrease health care costs.