Title: Is no additional excision after unplanned excision with positive margins justified in patients with small (≤5 cm) high-grade soft-tissue sarcoma?: Analysis from the Bone and Soft Tissue Tumor registry in Japan
Abstract: This study aimed to elucidate the clinical outcomes of patients with small (≤5 cm) high-grade soft tissue sarcoma, who underwent unplanned excision with positive surgical margin, using data from the Bone and Soft Tissue Tumor registry in Japan.We examined 174 patients (101 males and 73 females; mean age, 59 years) with primary non-metastatic soft tissue sarcoma. The tumor size was ≤5 cm, and tumor histological grade was high in all patients. The mean follow-up duration was 50 months.Unplanned excision with R1 and R2 margins was reported in 115 (66%) and 59 patients (34%), respectively. After unplanned excision, immediate additional excision was performed in 154 patients, whereas no additional excision was performed in the remaining 20. Of the 154 patients who underwent additional excision, wide surgical margin resection was achieved in 140 patients, while marginal and intralesional resections were achieved in 10 and 3 patients, respectively. Additionally, 93 patients (60%) underwent reconstruction after additional excision. During the last follow-up, 8 patients died of the disease, 22 developed distant metastasis, and 14 reported local recurrence. The 5-year disease-specific survival rate and 5-year metastasis-free survival rate was 93.5% and 85%, respectively. Tumor depth and additional excision after unplanned excision showed statistical significance in the multivariate analysis. The 5-year metastasis-free survival rate was 89.1% in patients with additional excision and 39.2% in those without. Univariate analysis showed an association between additional excision and local control. The 5-year local recurrence-free survival was significantly worse in patients without additional excision after unplanned excision (52.6%) than in those with additional excision (92.8%).If unplanned excision is performed in patients with small high-grade soft tissue sarcoma, additional excision is recommended for preventing metastasis, along with necessary preparations for reconstruction.