Background: Poor intra-tumoural vascularity contributes to a lack of response to chemotherapy in pancreatic cancers. Preliminary data suggest that the addition of endoscopic ultrasound (EUS)-guided intra-tumoural injection of phosphorus-32 (32P) microparticles to standard chemotherapy is potentially beneficial in locally advanced pancreatic cancer (LAPC). We aimed to assess changes in pancreatic tumour vascularity following32P implantation, using contrast-enhanced EUS (CE-EUS). Methods: This was a prospective single-centre trial from January 2022 to 2024 of patients with unresectable, non-metastatic LAPC undergoing standard FOLFIRINOX chemotherapy and32P implantation. We performed CE-EUS pre-implantation after two chemotherapy cycles and 4 and 12 weeks after implantation. Time–intensity curves were analysed for 90 s after IV contrast bolus to ascertain peak intensity and intensity gain. Results: A total of 20 patients underwent32P implantation, with 15 completing 12-week follow-up. The technical success of32P implantation was 100%. The median primary tumour size reduced from 32 mm (IQR 27.5–38.75) pre-implantation to 24 mm (IQR 16–26) 12 weeks post-implantation (p< 0.001). Five patients (25%) had tumour downstaging, and four underwent resections. The baseline (pre-implantation, post-chemotherapy) median intensity gain of contrast enhancement within the tumour was 32.15 (IQR 18.08–54.35). This increased to 46.85 (IQR 35.05–76.6;p= 0.007) and 66.3 (IQR 54.7–76.3;p= 0.001) at 4 weeks and 12 weeks post-implantation, respectively. Over a median follow-up of 11.2 months (IQR 7.8–12.8), 15/20 (75%) of patients remained alive, with 3/20 (15%) demonstrating local disease progression. Overall survival was not significantly different between patients with or without an increased intensity of 10 a.u. or more at 12 weeks post-implantation. Conclusion: This is the first clinical study to demonstrate treatment-induced increased vascularity within pancreatic primary tumours, which followed32P implantation and FOLFIRINOX chemotherapy. Larger comparative trials are warranted.
背景：胰腺癌肿瘤内血管分布不良是导致化疗反应不佳的原因之一。初步数据显示，在标准化疗基础上联合内镜超声引导下瘤内注射磷-32（32P）微粒对局部晚期胰腺癌可能具有潜在获益。本研究旨在通过对比增强内镜超声评估32P植入后胰腺肿瘤血管分布的变化。 方法：本项前瞻性单中心试验于2022年1月至2024年期间开展，纳入不可切除、无转移的局部晚期胰腺癌患者，所有患者均接受标准FOLFIRINOX化疗及32P植入治疗。我们在完成两个化疗周期后（植入前）以及植入后4周和12周分别进行对比增强内镜超声检查。通过分析静脉注射造影剂后90秒内的时间-强度曲线，确定峰值强度和强度增益值。 结果：共20例患者接受32P植入治疗，其中15例完成12周随访。32P植入技术成功率为100%。中位原发肿瘤尺寸从植入前的32毫米（四分位距27.5-38.75）缩小至植入后12周的24毫米（四分位距16-26）（p<0.001）。5例患者（25%）实现肿瘤降期，其中4例接受手术切除。肿瘤内对比增强的基线（植入前/化疗后）中位强度增益为32.15（四分位距18.08-54.35），在植入后4周和12周分别增至46.85（四分位距35.05-76.6；p=0.007）和66.3（四分位距54.7-76.3；p=0.001）。中位随访11.2个月（四分位距7.8-12.8）期间，20例患者中15例（75%）存活，3例（15%）出现局部疾病进展。植入后12周强度增益是否达到10个单位的患者之间，总生存期无显著差异。 结论：本研究首次通过临床证据表明，32P植入联合FOLFIRINOX化疗可诱导胰腺原发肿瘤血管分布增加。后续需要开展更大规模的对照试验加以验证。
肿瘤(癌症)患者之家