The Association Between Surgical Margin Status, Recurrence Patterns, and Oncologic Outcomes in Patients With...

To enhance understanding of the relationships between margin width, recurrence patterns, recurrence-free survival, and salvage therapy following initial hepatectomy for colorectal liver metastases (CRLM).

The prognostic implications of the technical aspects of CRLM have not been well-characterized.

A prospective database of 1776 patients who underwent complete resection for CRLM at a single institution (1991-2012) was studied. Pathologic margins were divided into positive, <1 mm, 1.0 to 9.9 mm, and ≥10 mm groups. Recurrence-free survival, patterns of initial and overall recurrence, including recurrence at the resection margin, and chance for salvage therapy, defined as complete eradication of recurrent disease, were compared by margin group.

Margin status was independently associated with an initially isolated liver recurrence [hazard ratio (HR; 95% CI) for positive: <1 mm, 1-9.9 mm vs ≥10 mm margin: 2.21 (1.49-3.26), 1.42 (0.84-2.40), 1.41 (1.08-1.84); P = 0.001]. Margin status was also independently associated with risk of initial recurrence at the resection margin [HR (95% CI) for positive: <1 mm, 1-9.9 mm vs ≥10 mm margin: 2.11 (1.26-3.54), 2.99 (1.74-5.15), 0.92 (0.62-1.37); P < 0.001] and risk of liver recurrence at any time [HR (95% CI) for positive: <1 mm, 1-9.9 mm vs ≥10 mm margin: 2.32 (1.79-3.01), 1.72 (1.23-2.42), 1.33 (1.11-1.58); P < 0.001]. The estimated 3-year cumulative incidence of overall recurrence at any site in the positive: <1 mm, 1 to 9.9 mm, and ≥10 mm margin groups was 70%, 70%, 57%, and 50%, respectively. Salvage therapy after recurrence increased with margin width ( P < 0.001).

Pathologic margin after resection of CRLM is associated with higher rates of overall recurrence that are less amenable to salvage and not just local failure. Margin status may be more of a reflection of underlying tumor characteristics rather than simply a risk factor for local failure.