Introduction: Stereotactic body radiotherapy (SBRT) is increasingly used to treat disease in the oligometastatic (OM) setting due to mounting evidence demonstrating its efficacy and safety. Given the low population representation in prospective studies, we performed a systematic review and meta-analysis of outcomes of HNC patients with extracranial OM disease treated with SBRT. Methods: A systematic review was conducted with Cochrane, Medline, and Embase databases queried from inception to August 2022 for studies with extracranial OM HNC treated with stereotactic radiotherapy. Polymetastatic patients (>five lesions), mixed-primary cohorts failing to report HNC separately, lack of treatment to all lesions, nonquantitative endpoints, and other definitive treatments (surgery, conventional radiotherapy, and radioablation) were excluded. The meta-analysis examined the pooled effects of 12- and 24-month local control (LC) per lesion, progression-free survival (PFS), and overall survival (OS). Weighted random-effects were assessed using the DerSimonian and Laird method, with heterogeneity evaluated using theI2statistic and Cochran Qtest. Forest plots were generated for each endpoint. Results: Fifteen studies met the inclusion criteria (639 patients, 831 lesions), with twelve eligible for quantitative synthesis with common endpoints and sufficient reporting. Fourteen studies were retrospective, with a single prospective trial. Studies were small, with a median of 32 patients (range: 6–81) and 63 lesions (range: 6–126). The OM definition varied, with a maximum of two to five metastases, mixed synchronous and metachronous lesions, and a few studies including oligoprogressive lesions. The most common site of metastasis was the lung. Radiation was delivered in 1–10 fractions (20–70 Gy). The one-year LC (LC1), reported in 12 studies, was 86.9% (95% confidence interval [CI]: 79.3–91.9%). LC2 was 77.9% (95% CI: 66.4–86.3%), with heterogeneity across studies. PFS was reported in five studies, with a PFS1 of 43.0% (95% CI: 35.0–51.4%) and PFS2 of 23.9% (95% CI: 17.8–31.2%), with homogeneity across studies. OS was analyzed in nine studies, demonstrating an OS1 of 80.1% (95% CI: 74.2–85.0%) and OS2 of 60.7% (95% CI: 51.3–69.4%). Treatment was well tolerated with no reported grade 4 or 5 toxicities. Grade 3 toxicity rates were uniformly below 5% when reported. Conclusions: SBRT offers excellent LC and promising OS, with acceptable toxicities in OM HNC. Durable PFS remains rare, highlighting the need for effective local or systemic therapies in this population. Further investigations on concurrent and adjuvant therapies are warranted.
引言：立体定向放射治疗（SBRT）因其疗效与安全性证据日益充分，在寡转移（OM）疾病治疗中的应用日趋广泛。鉴于前瞻性研究中人群代表性不足，本研究对接受SBRT治疗的颅外寡转移头颈癌（HNC）患者疗效进行系统综述与荟萃分析。方法：系统检索Cochrane、Medline及Embase数据库自建库至2022年8月期间关于立体定向放疗治疗颅外寡转移头颈癌的文献。排除标准包括：多发性转移（>5个病灶）、混合瘤种队列未单独报告头颈癌数据、未对所有病灶进行治疗、非量化终点指标、采用其他根治性治疗（手术、常规放疗、射频消融）。通过荟萃分析评估病灶水平的12个月及24个月局部控制率（LC）、无进展生存期（PFS）与总生存期（OS）的合并效应量，采用DerSimonian-Laird法进行加权随机效应评估，通过I²统计量与Cochran Q检验评估异质性，并为各终点指标绘制森林图。结果：共纳入15项研究（639例患者，831个病灶），其中12项符合定量合成标准（具有共同终点指标且数据报告充分）。14项为回顾性研究，仅1项为前瞻性试验。研究规模普遍较小，中位患者数32例（范围6-81），中位病灶数63个（范围6-126）。寡转移定义存在差异（最大转移灶数量2-5个），同时性与异时性转移灶混合存在，少数研究纳入寡进展病灶。肺是最常见转移部位。放疗分1-10次实施（总剂量20-70 Gy）。12项研究报告的1年局部控制率（LC1）为86.9%（95%置信区间[CI]：79.3-91.9%），LC2为77.9%（95% CI：66.4-86.3%），各研究间存在异质性。5项研究报告的PFS1为43.0%（95% CI：35.0-51.4%），PFS2为23.9%（95% CI：17.8-31.2%），研究间具有同质性。9项研究的OS分析显示OS1为80.1%（95% CI：74.2-85.0%），OS2为60.7%（95% CI：51.3-69.4%）。治疗耐受性良好，未报告4级或5级毒性反应，3级毒性发生率均低于5%。结论：SBRT对寡转移头颈癌患者展现出优异的局部控制率与良好的总生存前景，且毒性反应可接受。但持久无进展生存仍较罕见，提示该人群需要有效的局部或全身治疗策略，有必要进一步开展联合治疗与辅助治疗的相关研究。
肿瘤(癌症)患者之家