Adjuvant high-dose-rate and low-dose-rate brachytherapy with external beam radiation in soft tissue sarcoma: A comparison of outcomes

Purpose To compare outcomes of patients treated with low-dose-rate (LDR) adjuvant brachytherapy (BT) + external beam radiation therapy (EBRT) vs. high-dose-rate (HDR) adjuvant BT + EBRT. Methods and materials Thirty-seven patients with soft tissue sarcoma (STS) were treated with pre- or postoperative external beam irradiation and postoperative LDR or HDR BT. Results There was no significant difference in the 2-year local control rates (90% with LDR boost vs. 94% for HDR). The rate of National Cancer Institute (NCI) grades 2–4 wound-healing complications was 40% in the LDR group vs. 18% in the HDR group (p = 0.14). On univariate analysis, only suboptimal geometry of the implant predicted for increasing complication rate in the LDR group. In the HDR group, BT dose per fraction, total BT dose, and total biologically equivalent dose (BED3) radiation dose were significant. Conclusions HDR and LDR boost BT results in acceptable local control for STS. There is a suggestion that HDR may have lower incidence of severe (grade ≥3) acute toxicity than LDR.