Zunhao Zhang,1,* Bo Tian,1,* Hui Xu,1 He Huang,1 Xianwei Liang,1 Changwen Bo,1 Yunfei Bian,1 Ming Wei,2 Zhitao Zhao3 

1Department of Oncology, The First Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China; 2Department of General Surgery, Hebei Key Laboratory of Colorectal Cancer Precision Diagnosis and Treatment, The First Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, People’s Republic of China; 3Intensive Care Unit, The First Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Ming Wei, Department of General Surgery, Hebei Key Laboratory of Colorectal Cancer Precision Diagnosis and Treatment, The First Hospital of Hebei Medical University, Shijiazhuang City, Hebei Province, People’s Republic of China, Tel +86-18633888663, Email 314926509@qq.com Zhitao Zhao, Intensive Care Unit, The First Hospital of Hebei Medical University, Shijiazhuang, People’s Republic of China, Tel +86-18032808723, Email tsld60@163.com

Objective: This study aimed to investigate the effectiveness and safety of CyberKnife in the treatment of primary pancreatic cancer with metastases to the gastrointestinal tract (ie, primary pancreatic adenocarcinoma metastasizing to gastrointestinal organs).
Methods: A total of 106 patients with primary pancreatic cancer and metastases to the gastrointestinal tract admitted to our hospital received CyberKnife treatment. Recent treatment efficacy (assessed at 3 months post-treatment), median survival period, pain levels, and adverse reactions were analyzed.
Results: Among the 106 patients, 17 cases (16.04%) achieved complete response (CR), 61 cases (57.55%) achieved partial response (PR), 20 cases (18.87%) had stable disease (SD), and 8 cases (7.55%) had progressive disease (PD), resulting in an objective response rate (ORR) of 73.59% and an overall disease control rate (DCR) of 92.45% (98 cases). The one-year and two-year overall survival (OS) rates were 74.53% and 55.66%, respectively, while the local control (LC) rates were 92.45% and 87.74%, respectively. The median OS was 8.17 months (range: 1– 25 months). Mean pain scores (Visual Analog Scale) decreased significantly from 5.38± 1.37 at baseline to 2.01± 0.35 post-treatment (p< 0.001). Abdominal and lumbar pain significantly improved after 2 weeks of radiotherapy. Among the 68 patients with baseline pain who experienced relief, analgesic medication was discontinued in 25 (36.8%) patients, reduced by ≥ 50% in 18 patients (26.5%), and by approximately 25% in 5 patients (7.3%). Quality of life improved in 27 patients, remained stable in 52, and declined in 27, yielding an overall improvement or stabilization rate of 74.53% (79 cases).
Conclusion: CyberKnife SBRT appears to be a promising treatment modality for managing primary pancreatic cancer with metastases to the gastrointestinal tract, with minimal adverse reactions.

Keywords: CyberKnife, pancreatic cancer, gastrointestinal metastases, stereotactic body radiotherapy, survival outcomes