Patterns of local recurrence and risk of skin recurrence in soft tissue sarcomas after surgical resection. Practical radiation oncology Ewongwo, A., Oladipo, E. D., Hui, C., Avedian, R. S., Steffner, R. J., Mohler, D. G., Kalbasi, A., Chin, A. L., Million, L., Hiniker, S. M., Moding, E. J. 2023

Abstract

Although there is a theoretical risk of skin seeding during surgical resection of soft tissues sarcomas (STSs), current consensus guidelines recommend against routine use of bolus during RT. However, the risk of skin recurrence has not been systematically assessed. We aimed to assess the patterns of local recurrence (LR) in patients with STS treated with surgery with or without RT.We performed a retrospective analysis of adults with STSs evaluated at our institution between 2007-2021. For patients who developed LR, the depth was evaluated. Progression free survival (PFS) and overall survival (OS) were analyzed from time of first LR using Kaplan-Meier method. Cumulative incidence of distant metastasis (CIDM) was calculated with competing risk analysis from date of LR.Of the 206 patients evaluated, 20 had LR (9.7%). Among patients with LR, five patients (25.0%) were treated with surgery alone and 15 patients (75.0%) with surgery and RT. In patients treated with RT, 46.7% had pre-operative RT, 53.3% had post operative RT, and bolus was used in 46.7%. Surgical margins were close (<1mm) in 4 patients (20.0%) and positive in 10 patients (50.0%). LR occurred in the deep subfascial tissue in 9 patients (45%), subcutaneous tissue in 10 patients (50.0%), and skin in 1 patient (5.0%). The patient with a skin recurrence was treated with surgery alone and the tumor involved the skin at presentation. In patients treated with RT, LR occurred within RT field in 13 patients (86.7%). At 1 year after LR, PFS was 70.3%, OS was 81.7%, and CIDM was 5.9%.Skin recurrences were rare after surgical resection of STSs, and only occurred in a tumor that involved the skin at initial presentation. These findings support current recommendations against routine use of bolus in STSs not involving the skin at presentation.

View details for DOI 10.1016/j.prro.2023.09.006

View details for PubMedID 37804883