The Impact of Margin Status on the Oncologic Outcomes of Surgically Treated Dedifferentiated Liposarcoma of the Extremities

Abstract

Background. Dedifferentiated liposarcoma (DDLPS) is an aggressive subtype of liposarcoma that can arise within an atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLs). The primary goal of treatment for DDLPS is wide-margin resection, but it remains unclear if ALT/WDLs surrounding DDLPS also necessitates wide-margin resection for optimal local control. Methods. Patients treated surgically for a biopsy showing DDLPS at a single institution were identified. Margin status for both DDLPS and ALT/WDLs were categorized into one of the following categories: wide, marginal or intralesional. All patients were categorized as either “wide throughout” or “wide on DDLPS, marginal on ALT/WDLs”. Chi-square tests were used to compare margin status and oncologic outcome. Results. Eighteen patients met the inclusion criteria for the study. Twelve patients had surgical margins wide on DDLPS/marginal on ALT/WDLs, and 6 patients had surgical margins wide throughout. Two patients with surgical margins wide on DDLPS/marginal on ALT/WDLs developed local recurrence compared with no patients with margins wide throughout (P = .289). Six patients with surgical margins wide on DDLPS/marginal on ALT/WDLs developed metastases compared to 1 patient with margins wide throughout (P = .289). Conclusions. Compared with patients with wide margins throughout, patients with margins wide on DDLPS/marginal on ALT/WDLs had more local recurrences, new metastases, and death from disease. While no statistically significant difference was found between subgroups for these comparisons, cohort size limits our ability to conclude that no clinical difference exists. This study forms the basis for a future, larger, multi-institutional study to improve external validity and power to identify clinically relevant differences.