P37. Reconstructing Soft Tissue Sarcoma Patients: Tumor Bed Excision Defects Are Deceiving and Result in Higher Reoperation Rates

PURPOSE: Soft Tissue Sarcomas (STS) may be misdiagnosed and/or inadequately resected, leaving behind microscopic disease that necessitates a secondary Tumor Bed Excision (TBE). Little is known about these patients' course and outcomes given the rarity of centers treating them. METHODS: We retrospectively analyzed reconstructed cases from 2016 to 2021, comparing TBE to mass excisions (ME). Demographics, oncological variables, reconstructive techniques, and outcomes were included. Parametric and non-parametric comparisons were employed as appropriate. RESULTS: In contrast to STS ME, TBE patients were mostly females, had shorter hospital stays, longer follow-up periods, and more plastic surgery involvement (p<0.05). The two groups differed significantly in sarcoma locations, pathologies, and defect dimensions, with TBE being smaller than ME (p<0.05). TBE had significantly greater rates of reoperation (16% vs. 8.5%; p=0.03) and graft loss (38.9% vs. 15.6%; p<0.001), but overall complications were similar between the groups (39.6% vs. 31.3%; p=0.13). CONCLUSION: Although TBE defects are significantly smaller, they have a greater reoperation rate. While both TBE and ME defects stem from STS excisions, they seem to differ clinically from a wound-healing perspective. Plastic Surgeons should consider advanced reconstructive options, especially for TBE defects.