Pandemic driven preoperative moderate hypofractionated radiotherapy for soft tissue sarcomas

Moderate hypofractionation was adopted to reduce hospital visits during the COVID-19 pandemic aiming to maintain treatment efficacy for soft tissue sarcoma (STS) patients, shifting preoperative schedules from 25 fractions of 2 Gy to 14-15 fractions of 3 Gy. This study evaluates the clinical implications and outcomes of this schedule, focusing on wound complications, radiation toxicity, local tumour control, and distant metastases.

Data was collected from patients treated between 01 and 01-2020 and 31-12-2023. Outcomes included wound complications within 120 days post-surgery, local-recurrence, distant metastases and radiation toxicity. Logistic regression was performed to identify factors associated with wound complications. The cumulative incidence of local recurrence and distant metastases were estimated with a competing risk model.

Sixty-six patients were analysed, with a mean age of 74 years (standard deviation (SD)± 11). Tumours were mainly localized in the lower extremities (64 %), mean size 103 mm (SD±58). Median follow-up was 29 months (range 2-50). A R0 resection margin was achieved in 77 % of the operated patients. The wound complication rate was 33 %, with moderate complications in 13 patients and severe in 6. The cumulative incidences of local recurrence and distant metastases at 2 years were 7.6 % (standard error (SE) 3.7 %) and 29 % (SE 6 %, Fig. 1) respectively. Acute grade 3 dermatitis occurred in one patient (1.5 %)and two patients experienced late grade 3 toxicity (fractures, 3.0 %). Twenty patients developed distant metastases, two diagnosed before start of the treatment. Eighteen patients died, with six deaths from distant metastases and one from the primary tumour.

Preoperative moderate hypofractionation for STS during COVID-19 showed promising results, with no increase in postoperative wound complications and favourable local failure rates.