Breast Cancer Update for Surgeons, Issue 1, 2017 (Video Program)Consensus guidelines on margins for BCS with whole breast irradiation in patients with DCIS
2:39 minutes.
TRANSCRIPTION:
DR KING: Dr Morrow and colleagues, they did a very intensive systematic review of the literature, of all the papers that were published that looked at in-breast recurrence following conservative treatment for DCIS, looking at what margin widths were reported. The meta-analysis was, again, performed, looking to see if there is an optimal margin width that reduces the risk of in-breast recurrence. And then a consensus conference was held where experts from the different groups, the SSO, ASTRO and ASCO, came together to discuss the results of the meta-analysis and to put together the consensus statement on what is an adequate margin width. And the final result, as you said, was that in pure DCIS, it appears that a margin width of 2 millimeters is associated with low rates of local recurrence. And there’s no benefit to a wider margin than 2 millimeters for reducing local recurrence in women who are going to receive radiation therapy. Now, there is a series from Memorial Sloan Kettering — Dr Kim Van Zee is the senior author — a large group of women treated conservatively for DCIS, the majority of whom did receive radiation therapy. But when you look at the large number of women in that series who did not receive radiation therapy, in those women it does appear like margin width may actually correlate with risk of recurrence. So in women not receiving radiation, it may be that the wider margin is better. But in women receiving radiation therapy, the 2 millimeters is what was determined to be the appropriate width based on the meta-analysis. DR LOVE: I’m kind of curious. What was your approach to margin width or margins in general with DCIS before this paper, and did it change? DR KING: So in general with margins, at Memorial we always had a range that we liked, 1- to 2-mm margin on DCIS. We certainly did not use the same tumor on ink as we use in invasive cancer, but we didn’t have a real strict cutoff. And certainly there are patient factors and tumor factors that come into play. Which margin is it that might be close? What’s the age of the patient? Again, is she going to receive radiation and what not? So we didn’t have a hard and fast rule, but most of us did go for a 1- to 2-mm margin in DCIS. |