Resection margins constitute a recognized risk factor for local recurrence, but their impact on survival is less clear.

Infiltrative proliferation and satellite nodules are prognostic factors for local and systemic aggressiveness.

Retrospective cohort study.

In 105 patients under curative treatment, resection quality was assessed on UICC criteria (R0/R1) and on a modified version (R0M/R1M) taking account of proliferation contours and satellite nodules for narrow margins (<1mm). Uni- and multi-variate analysis was performed, and Kaplan-Meier survival curves were compared on log-rank.

Mean 5-year local recurrence-free survival (LRFS) was 0.64 [0.52–0.76] after R1 surgery, 0.9 [0.85–0.95] after R0, 0.64 [0.519–0.751] after R1M and 0.92 [0.87–0.96] after R0M. Resection type according to R classification correlated with disease-free survival (DFS) (P=0.028), but not with metastasis-free survival (MFS) (P=0.156). Resection type according to RM classification correlated with DFS and MFS. Multivariate analysis disclosed correlations between LRFS rate and RM resection type (HR 6.77 [1.78–25.7], P=0.005), DFS rate and RM resection type (HR 2.83 [1.47–5.43], P=0.001) and grade (HR=3.17 [1.38–7.27], P=0.003), and MFS and grade (HR=3.96 [1.50–10.5], P=0.006).

The microscopic aspect of the proliferation contours and presence of satellite nodules were confirmed as prognostic factors for local and systemic aggressiveness. They impact both disease-free survival and metastasis-free survival in case of margins less than 1mm. Their systematic consideration may help identify patients with elevated systemic risk.

IV.