Abstract

The recommended post-operative radiotherapy dose of approximately 60 Gy may be reduced during treatment planning, and the optimal irradiation method and dose remain unclear. We aimed to clarify the usefulness and safety of post-operative radiotherapy for soft tissue sarcomas. Forty-five patients with soft-tissue sarcomas who underwent adjuvant radiotherapy at two institutions from June 2014 to August 2020 were included. Patients with a high risk of recurrence underwent post-operative irradiation, with doses of 60–70 Gy and 50 Gy used in patients with positive and negative resection margins, respectively. The median patient age was 72 (21–88) years. The most common histological types of sarcomas were myxofibrosarcoma (n = 12) and dedifferentiated liposarcoma (n = 11), followed by other sarcomas. Thirty patients were newly diagnosed, and 15 underwent surgery for localized recurrent disease. Thirty-two and 13 patients underwent wide and marginal resection, respectively. Surgical margins were negative in 12 patients and positive in 33 patients. Chemotherapy was administered before or after radiotherapy in 16 patients. The 2-year local control, progression-free survival, and overall survival rates after post-operative radiotherapy were 88%, 78%, and 93%, respectively. In patients with positive resection margins, doses of ≥ 60 Gy contributed to local control (p = 0.0002, log-rank test) and progression-free survival (p = 0.0033). Late grade 3 adverse events were observed in 7% of the patients. Post-operative radiotherapy for soft tissue sarcomas is safe and effective, with high doses (≥ 60 Gy) contributing to reduced recurrence among patients with positive resection margins.

中文翻译：

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软组织肉瘤辅助放疗的疗效和安全性：两机构回顾性观察研究

摘要

在治疗计划期间可能会减少建议的术后放疗剂量约60 Gy，但最佳照射方法和剂量仍不清楚。我们的目的是阐明软组织肉瘤术后放疗的有用性和安全性。纳入2014年6月至2020年8月期间在两个机构接受辅助放疗的45例软组织肉瘤患者。复发风险高的患者接受术后放疗，对于切缘阳性和阴性的患者分别使用60-70 Gy和50 Gy的剂量。患者中位年龄为 72 (21–88) 岁。最常见的肉瘤组织学类型是粘液纤维肉瘤（n  = 12）和去分化脂肪肉瘤（n  = 11），其次是其他肉瘤。 30 例新诊断患者，15 例因局部复发性疾病接受手术。 32 名患者和 13 名患者分别接受了广泛切除术和边缘切除术。 12 名患者的手术切缘呈阴性，33 名患者的手术切缘呈阳性。 16 名患者在放疗之前或之后进行了化疗。术后放疗后2年局部控制率、无进展生存率和总生存率分别为88%、78%和93%。对于切除边缘阳性的患者，≥ 60 Gy 的剂量有助于局部控制（p  = 0.0002，对数秩检验）和无进展生存期（p  = 0.0033）。 7% 的患者观察到晚期 3 级不良事件。软组织肉瘤的术后放疗安全有效，高剂量（≥ 60 Gy）有助于减少切缘阳性患者的复发。