(P 28) THE INFLUENCE OF MARGINS ON OUTCOME IN CUTANEOUS LOCATED SOFT TISSUE SARCOMAS IN THE HEAD AND NECK

Objective: The primary treatment for cutaneous located sarcomas involves wide surgical excision. However, obtaining wide surgical margins in the head and neck can be challenging. Up till now, evidence is lacking on whether surgical margins can be safely reduced for this rare cancer type. In this study we present results from the surgical treatment of cutaneous located head and neck sarcomas to gain more insight into the impact of achieved surgical margins on local recurrence-free survival.

Methods: This retrospective study analyzed all consecutive patients treated for a cutaneous located head and neck sarcoma between 1998 and 2021. Data on patient and tumor characteristics, treatment, margins, and follow-up were collected. Patients were divided into three margin categories based on the outcome of their last excision: 1) clear margins (R0), 2) no tumor in resected material, and 3) no clear margin (R1/2). The effect of the margin category on local recurrence was evaluated. For patients in the R0 group, an optimum cut-off value for resection margins predicting local recurrence was defined, and the effect of having a margin below or above the cut-off on local recurrence was evaluated.

Results: For analysis, we included 95 patients who underwent surgical resection for a cutaneous located head and neck sarcoma, including angiosarcoma, atypical fibroxanthoma, dermal pleiomorphic sarcoma, dermatofibrosarcoma protuberans, leiomyosarcoma, low-grade fibromyxoid sarcoma, and sarcoma NOS. The 5-year recurrence-free survival of all patients was 80.0%, with a hazard ratio of 4.4 [HR 4.4; CI95% 1.7 – 11.3] for patients without clear margins compared with R0 resection. Analysis of patients with an R0 resection showed no difference in local recurrence-free survival between a margin below or above the optimum cutoff value of 0.5 mm (p = 0.84).

Conclusion: These data suggest that obtaining smaller margins can be safe for certain cutaneous soft tissue sarcomas in the head and neck area, although further research is necessary to determine the optimal margin for each specific subtype.