Background/Objectives: Patients diagnosed with pancreatic ductal adenocarcinoma (PDAC) have a poor prognosis. Local therapy may enhance tumor control and increase resectability. Intratumoral injection of radioactive holmium-166 microspheres presents a promising and minimally invasive treatment with multimodality imaging capabilities (SPECT, CT, MRI). However, holmium-166 microspheres are not commonly used for intratumoral injections, and PDAC is notorious for its high intratumoral pressure. This study developed an intratumoral injection method with nonradioactive holmium-165 microspheres in ex vivo human PDAC specimens using a novel injection system for suspension homogenization. Methods: An injection system was developed and validated in a laboratory setting. Thereafter, intratumoral injections in surgically removed ex vivo PDACs were performed, and parameters were established to optimize feasibility, defined by the ability to inject and control the microsphere distribution. Also, injection limitations and cutoff values were determined. The distribution was assessed by visual confirmation, CT, MRI, ultrasound, and histopathology. Results: With a validated injection system, intratumoral injections were performed in ten ex vivo PDAC samples. Feasible injection guidelines include but are not limited to ultrasound or CT needle guidance, a maximum injection volume of <20.0% from the tumor volume, ≤3 needle positions, and an injection volume of 0.3–1.0 mL per needle position. Conclusions: Intratumoral injection of holmium-165 microspheres in ex vivo pancreatic ductal adenocarcinoma was feasible with adherence to injection parameters necessary for effective intratumoral deposition and minimal leakage. The injection system and parameters developed here provide a foundation for future studies on holmium-166 microsphere injections in pancreatic cancer patients, with the aim to improve local tumor control as a part of a multimodal therapy.
背景/目的：胰腺导管腺癌（PDAC）患者预后较差。局部治疗可能增强肿瘤控制并提高可切除性。瘤内注射放射性钬-166微球是一种具有多模态成像能力（SPECT、CT、MRI）且前景广阔的微创治疗方法。然而，钬-166微球在瘤内注射中并不常用，且PDAC以其瘤内高压而著称。本研究采用新型悬浮均质化注射系统，在离体人PDAC标本中开发了非放射性钬-165微球的瘤内注射方法。方法：在实验室环境中开发并验证了一种注射系统。随后，在手术切除的离体PDAC标本中进行瘤内注射，并建立参数以优化可行性（定义为能够注射并控制微球分布）。同时确定了注射限制和临界值。通过目视确认、CT、MRI、超声和组织病理学评估分布情况。结果：使用经验证的注射系统，在十个离体PDAC样本中进行了瘤内注射。可行的注射指南包括但不限于：超声或CT引导下进针、最大注射体积小于肿瘤体积的20.0%、≤3个注射针位、每个针位注射体积为0.3–1.0 mL。结论：在离体胰腺导管腺癌中进行钬-165微球的瘤内注射是可行的，但需遵循确保有效瘤内沉积和最小泄漏的必要注射参数。本研究开发的注射系统和参数为未来在胰腺癌患者中进行钬-166微球注射的研究奠定了基础，旨在作为多模式治疗的一部分改善局部肿瘤控制。
肿瘤(癌症)患者之家