Li Jim Zhang Hao, Kong Timothy, Dunne Emma M, Liu Mitchell, Chang Jee Suk, Zhang Tina Wanting, Chan Matthew, McDermott Ronan
Division of Radiation Oncology and Developmental Radiotherapeutics, BC Cancer - Vancouver, Vancouver, CAN.
Cureus. 2025 Aug 8;17(8):e89630. doi: 10.7759/cureus.89630. eCollection 2025 Aug.
Introduction In select tumor sites, symptom palliation and local control can be improved through delivering higher biological equivalent doses (BED) of radiotherapy. However, not all patients are suitable candidates for stereotactic body radiation therapy (SBRT). The 30 Grays in five fractions (30/5) regimen is a conformal, hypofractionated regimen that offers a higher BED compared to conventional palliative radiotherapy. It adheres to the same organ-at-risk constraints as five-fraction SBRT. The planning and set-up processes are optimized to expedite treatment delivery compared to SBRT. This study aims to assess the oncologic and safety profiles of the 30/5 regimen. Methods Clinical data of patients who received the 30/5 regimen between October 2020 and August 2022 at our institution, the BC Cancer Vancouver Centre, were retrospectively reviewed. Local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), time to change in systemic therapy (CIS), and overall survival (OS) were calculated using the Kaplan-Meier method. Survival distributions between groups were compared using the log-rank test. Univariable and multivariable analyses were performed using Cox regression analysis to identify factors associated with the oncologic outcomes. Results Over 22 months, 77 patients received 92 courses of the 30/5 regimen. The median age was 68 years. The median tumor size treated was 11.4 cm. The most common treatment locations were lung (34%), lymph nodes (21%), non-spine bone (18%), and spine (15%). At a median follow-up of 13.5 months, 29 deaths were observed. The 12-month LC was 66.1% (95% CI: 55.7-76.5%), and the 12-month DMFS, PFS, CIS, and OS were 35.9% (95% CI: 24.5-47.3%), 33.2% (95% CI: 22.0-44.4%), 59.2% (95% CI: 46.8-71.5%), and 72.5% (95% CI: 62.1-82.9%), respectively. The univariable analysis showed that radiosensitive and smaller tumors had better LC outcomes (p=0.005 and <0.001, respectively). These associations remained significant upon multivariable analysis too (p=0.035 and 0.026, respectively). No grade three or higher toxicity was reported. Conclusion The 30/5 regimen demonstrates good local control and favorable safety profile, particularly for small and radiosensitive tumors. Our findings suggest that 30/5 may be a viable alternative palliative regimen for patients who require high-dose radiotherapy, but are not suitable candidates for SBRT or prolonged interruptions in systemic therapy. In resource-limited settings, its hypofractionated approach may help conserve healthcare resources. Future studies are warranted to prospectively evaluate the impact of dosimetric distribution on oncologic outcomes.
引言 在某些肿瘤部位，通过给予更高的生物等效剂量（BED）放疗可改善症状缓解和局部控制情况。然而，并非所有患者都适合立体定向体部放疗（SBRT）。30格雷分五次照射（30/5）方案是一种适形、大分割方案，与传统姑息性放疗相比，其生物等效剂量更高。它与五次分割的SBRT遵循相同的危及器官限制。与SBRT相比，该方案的计划和摆位过程经过优化，以加快治疗实施。本研究旨在评估30/5方案的肿瘤学和安全性。
方法 回顾性分析了2020年10月至2022年8月期间在我们机构——卑诗癌症温哥华中心接受30/5方案治疗的患者的临床数据。采用Kaplan-Meier法计算局部控制（LC）、无远处转移生存期（DMFS）、无进展生存期（PFS）、全身治疗改变时间（CIS）和总生存期（OS）。使用对数秩检验比较组间生存分布。采用Cox回归分析进行单变量和多变量分析，以确定与肿瘤学结局相关的因素。
结果 在22个月期间，77例患者接受了92疗程的30/5方案治疗。中位年龄为68岁。治疗的肿瘤中位大小为11.4厘米。最常见的治疗部位是肺部（34%）、淋巴结（21%）、非脊柱骨（18%）和脊柱（15%）。中位随访13.5个月时，观察到29例死亡。12个月时的局部控制率为66.1%（95%CI：55.7 - 76.5%），12个月时的无远处转移生存期、无进展生存期、全身治疗改变时间和总生存期分别为35.9%（95%CI：24.5 - 47.3%）、33.2%（95%CI：22.0 - 44.4%）、59.2%（95%CI：46.8 - 71.5%）和72.5%（95%CI：62.1 - 82.9%）。单变量分析显示，放射敏感和较小的肿瘤局部控制结局更好（p分别为0.005和<0.001）。多变量分析时这些关联也仍然显著（p分别为0.035和0.026）。未报告三级或更高等级的毒性反应。
结论 30/5方案显示出良好的局部控制和良好的安全性，特别是对于小的和放射敏感的肿瘤。我们的研究结果表明，对于需要高剂量放疗但不适合SBRT或全身治疗长期中断的患者，30/5可能是一种可行的替代姑息方案。在资源有限的环境中，其大分割方法可能有助于节省医疗资源。未来有必要进行前瞻性研究，以评估剂量分布对肿瘤学结局的影响。
