Table_2_Clinical Effects of Stereotactic Body Radiation Therapy Targeting the Primary Tumor of Liver-Only Oligometastatic Pancreatic Cancer.docx

AimTo investigate the efficacy and safety of stereotactic body radiotherapy (SBRT) targeting the primary tumor for liver-only oligometastatic pancreatic cancer.
MethodsWe compared the efficacy and safety of SBRT plus chemotherapy with chemotherapy alone in patients with liver-only oligometastatic pancreatic cancer. The populations were balanced by propensity score-weighted and propensity score-matched analyses based on baseline variables. The primary outcome was overall survival (OS). The secondary outcomes included progression free survival (PFS), local progression, metastatic progression and symptomatic local control.
ResultsThis is a retrospective study of 89 pancreatic cancer patients with liver-only oligometastasis. Overall, 34 (38.2%) and 55 (61.8%) patients received SBRT plus chemotherapy and chemotherapy alone, respectively. After propensity score matching, 1-year OS rate was 34.0% (95%CI, 17.8-65.1%) in the SBRT plus chemotherapy group and 16.5% (95%CI, 5.9-46.1%) in chemotherapy alone group (P=0.115). The 6-month PFS rate was 29.4% (95%CI, 15.4-56.1) in SBRT plus chemotherapy and 20.6% (95%CI, 8.8-48.6) in chemotherapy alone group (P=0.468), respectively. Further subgroup analysis indicated that the addition of SBRT improved OS in patients with primary tumor located in the head of pancreas (stratified HR, 0.28; 95% CI, 0.09 to 0.90) or good performance status (stratified HR, 0.24; 95% CI, 0.07 to 0.86). In terms of disease control, SBRT delayed local progression of pancreas (P=0.008), but not distant metastatic progression (P=0.56). Besides, SBRT offered significant abdominal/back pain relief (P=0.016) with acceptable toxicities.
ConclusionsThe addition of SBRT to chemotherapy in patients with liver-only oligometastatic pancreatic cancer improves the OS of those with primary tumor located in the head of pancreas or good performance status. In addition, it is a safe and effective method for local progression control and local symptomatic palliation in patients with metastatic pancreatic cancer.

研究目的 本研究旨在探讨针对仅伴肝脏寡转移的胰腺癌患者原发灶的立体定向体部放疗（stereotactic body radiotherapy, SBRT）的有效性与安全性。
方法 本研究对比了仅伴肝脏寡转移的胰腺癌患者接受SBRT联合化疗与单纯化疗的有效性与安全性。研究人群基于基线变量，通过倾向得分加权及倾向得分匹配分析实现组间均衡。主要研究终点为总生存期（overall survival, OS），次要研究终点包括无进展生存期（progression free survival, PFS）、局部进展、远处转移进展及症状性局部控制。
结果 本研究为一项纳入89例仅伴肝脏寡转移的胰腺癌患者的回顾性研究。最终共有34例（38.2%）患者接受SBRT联合化疗，55例（61.8%）患者接受单纯化疗。经倾向得分匹配后，SBRT联合化疗组的1年总生存率为34.0%（95%CI：17.8%~65.1%），单纯化疗组为16.5%（95%CI：5.9%~46.1%）（P=0.115）。SBRT联合化疗组的6个月无进展生存率为29.4%（95%CI：15.4%~56.1%），单纯化疗组为20.6%（95%CI：8.8%~48.6%）（P=0.468）。进一步亚组分析显示，对于原发灶位于胰头或体能状态良好的患者，加用SBRT可改善其总生存期（分层风险比，0.28；95%CI：0.09~0.90；分层风险比，0.24；95%CI：0.07~0.86）。在疾病控制方面，SBRT可延缓胰腺癌局部进展（P=0.008），但未显著影响远处转移进展（P=0.56）。此外，SBRT可显著缓解患者腹部及背部疼痛（P=0.016），且毒性反应可耐受。
结论 对于仅伴肝脏寡转移的胰腺癌患者，在化疗基础上加用SBRT可改善原发灶位于胰头或体能状态良好患者的总生存期。此外，对于转移性胰腺癌患者，SBRT是一种安全有效的局部进展控制及局部症状缓解手段。