Impact of resection margin on outcomes in high-grade soft tissue sarcomas of the extremity-A USSC analysis

Impact of resection margin on outcome in soft-tissue sarcomas of the extremities treated with limb-sparing surgery and postoperative radiotherapy

BACKGROUND

The standard curative treatments for extremity soft tissue sarcoma (ESTS) include surgical resection with negative margins and perioperative radiotherapy. However, the optimal resection margin remains controversial. This study aimed to evaluate the outcomes in ESTS between microscopically positive margin (R1) and microscopically negative margin (R0) according to the Union for International Cancer Control (UICC) (R + 1 mm) classification.

METHODS

Medical records of patients with localized ESTS who underwent primary limb-sparing surgery and postoperative radiotherapy between 2004 and 2015 were retrospectively reviewed. Patients were followed for at least 5 years or till local or distant recurrence was diagnosed during follow-up. Outcomes were local and distal recurrences and survival.

RESULTS

A total of 52 patients were included in this study, in which 17 underwent R0 resection and 35 underwent R1 resection. No significant differences were observed in rates of local recurrence (11.4% vs. 35.3%, p = 0.062) or distant recurrence (40.0% vs. 41.18%, p = 0.935) between R0 and R1 groups. Multivariate analysis showed that distant recurrences was associated with a Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) grade (Grade III vs. I, adjusted hazard ratio (aHR): 12.53, 95% confidence interval (CI): 2.67-58.88, p = 0.001) and tumor location (lower vs. upper extremity, aHR: 0.23, 95% CI: 0.07-0.7, p = 0.01). Kaplan-Meier plots showed no significant differences in local (p = 0.444) or distant recurrent-free survival (p = 0.161) between R0 and R1 groups.

CONCLUSIONS

R1 margins, when complemented by radiotherapy, did not significantly alter outcomes of ESTS as R0 margins. Further studies with more histopathological types and larger cohorts are necessary to highlight the path forward.

Preoperative ultra-hypofractionation radiotherapy in extremity/trunk wall soft tissue sarcoma - A meta-analysis of prospective studies

PURPOSE

The neoadjuvant radiotherapy is now standard treatment in soft tissue sarcoma. Using ultra-hypofractionation radiotherapy shorten the treatment time. In the era of COVID pandemic, using less fraction to treat patient is an urgent need. Thus, we aim to use meta-analysis to investigate the clinical efficacy of preoperative stereotactic body radiotherapy.

MATERIAL AND METHODS

PRISMA guideline was used in this study. PubMed, Cochrane and Embase were used. We include only prospective study. The main endpoint was set as wound complication rate. Other endpoints include R0 resection rate, overall survival, local control, and distant metastasis free survival.

RESULTS

Seven studies were included. The pooled wound complication rate is 0.30 (95% CI=0.26-0.35). The pooled R0 resection rate is 0.87(95%CI: 0.74-0.94). The pooled 2-year overall survival is 0.86 (95%CI: 0.72-0.94). The pooled 2-year local control rate is 0.96(95%CI: 0.89-0.99). The pooled 2-year distant metastasis free survival is 0.60 (95%CI=0.50-0.70).

CONCLUSION

Neoadjuvant ultra-hypofractionation radiotherapy in soft tissue sarcoma is a feasible and well tolerable treatment.