Background: Pediatric patients with metastatic and/or recurrent solid tumors have poor survival outcomes despite standard-of-care systemic therapy. Stereotactic ablative radiation therapy (SABR) may improve tumor control. We report the outcomes with the use of SABR in our pediatric solid tumor population. Methods: This was a single-institutional study in patients < 30 years treated with SABR. The primary endpoint was local control (LC), while the secondary endpoints were progression-free survival (PFS), overall survival (OS), and toxicity. The survival analysis was performed using Kaplan–Meier estimates in R v4.2.3. Results: In total, 48 patients receiving 135 SABR courses were included. The median age was 15.6 years (interquartile range, IQR 14–23 y) and the median follow-up was 18.1 months (IQR: 7.7–29.1). The median SABR dose was 30 Gy (IQR 25–35 Gy). The most common primary histologies were Ewing sarcoma (25%), rhabdomyosarcoma (17%), osteosarcoma (13%), and central nervous system (CNS) gliomas (13%). Furthermore, 57% of patients had oligometastatic disease (≤5 lesions) at the time of SABR. The one-year LC, PFS, and OS rates were 94%, 22%, and 70%, respectively. No grade 4 or higher toxicities were observed, while the rates of any grade 1, 2, and 3 toxicities were 11.8%, 3.7%, and 4.4%, respectively. Patients with oligometastatic disease, lung, or brain metastases and those who underwent surgery for a metastatic site had a significantly longer PFS. LC at 1-year was significantly higher for patients with a sarcoma histology (95.7% vs. 86.5%,p= 0.01) and for those who received a biological equivalent dose (BED10) > 48 Gy (100% vs. 91.2%,p= 0.001). Conclusions: SABR is well tolerated in pediatric patients with 1-year local failure and OS rates of <10% and 70%, respectively. Future studies evaluating SABR in combination with systemic therapy are needed to address progression outside of the irradiated field.
背景：尽管接受了标准系统性治疗，转移性和/或复发性实体瘤儿科患者的生存结局仍不理想。立体定向消融放射治疗（SABR）可能改善肿瘤控制。本研究旨在报告SABR在儿科实体瘤患者群体中的应用效果。 方法：本研究为单中心研究，纳入年龄<30岁接受SABR治疗的患者。主要终点为局部控制率（LC），次要终点包括无进展生存期（PFS）、总生存期（OS）及毒性反应。采用R v4.2.3软件中的Kaplan-Meier法进行生存分析。 结果：共纳入48例患者，累计接受135次SABR治疗。中位年龄15.6岁（四分位距IQR 14-23岁），中位随访时间18.1个月（IQR 7.7-29.1）。SABR中位剂量为30 Gy（IQR 25-35 Gy）。最常见的原发肿瘤组织学类型包括尤文肉瘤（25%）、横纹肌肉瘤（17%）、骨肉瘤（13%）和中枢神经系统胶质瘤（13%）。57%的患者在SABR治疗时为寡转移状态（≤5个病灶）。1年LC率、PFS率和OS率分别为94%、22%和70%。未观察到4级及以上毒性反应，1级、2级和3级毒性反应发生率分别为11.8%、3.7%和4.4%。寡转移患者、肺或脑转移患者以及接受转移灶手术的患者PFS显著延长。肉瘤组织学类型患者（95.7% vs 86.5%，p=0.01）和接受生物等效剂量（BED10）>48 Gy患者（100% vs 91.2%，p=0.001）的1年LC率显著更高。 结论：SABR在儿科患者中耐受性良好，1年局部失败率<10%，总生存率达70%。未来需要开展SABR联合系统性治疗的研究，以解决照射野外的疾病进展问题。
肿瘤(癌症)患者之家