Changes in margin re‐excision rates: Experience incorporating the “no ink on tumor” guideline into practice

Abstract

The implementation of the "no ink on tumor" guideline at our institution has resulted in a significant decrease in positive margin rates and a numerical decrease in margin re-excisions. In addition to margin status, surgeons continue to use individual patient and histologic factors to decide for or against margin re-excision.

Histologic margins and the residual tumour classification scheme: Is it time to use a validated scheme in human oncology to standardise margin assessment in veterinary oncology?

“…Histologic margins are commonly described as being incomplete or complete, with incomplete histologic margins being defined as neoplastic cells extending to the edge of the surgical resection margins or 'tumour on ink'. [1][2][3][4][5][6] However, in some studies, an incomplete histologic excision has been arbitrarily defined as a HTFM ≤1 mm, [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] ≤2 mm 23 or ≤5 mm. 24 The assessment of histologic margins is further complicated by the common use of 'close' or 'narrow' histologic margins in veterinary oncology.…”

“…Histologic margins are commonly described as being incomplete or complete, with incomplete histologic margins being defined as neoplastic cells extending to the edge of the surgical resection margins or ‘tumour on ink’ . However, in some studies, an incomplete histologic excision has been arbitrarily defined as a HTFM ≤1 mm, ≤2 mm or ≤5 mm .…”

Defining Why the Re-excision Rate Dropped

“…The work, encompassing two national studies, as well as five institutional ones, documents what would be the logical outcome-that when one changes the definition of what is a positive margin requiring re-excision to become more narrow, the re-excision rates decline. [2][3][4][5][6][7][8] Problematic, however, is that they could not actually document why re-excisions decreased. Was it really the change in definition?…”

Reoperation rate after breast conserving surgery as quality indicator in breast cancer treatment: A reappraisal

“…In 2014 and 2016 the Society of Surgical Oncology (SSO), the American Society for Radiation Oncology (ASTRO) and the American Society of Clinical Oncology (ASCO) recognized “no ink on tumor” as the standard for an adequate margin for invasive breast cancer and a 2 mm margin as the standard for DCIS [ 22 , 23 ]. Several studies reported a reduction of RBS rates by comparing series before and after the release of these guidelines ( Table 4 ) [ [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] ], which was confirmed by a recently published meta-analysis [from 22% to 14%; Odds Ratio (OR) 0.65; 95% Confidence Interval (CI) 0.54–0.78; p < 0.0001) [ 33 ].…”