Proschek D, Mack M G, Kurth A A, Proschek P, Martin B, Hansmann M L, Vogl T J
Department of Orthopaedic and Trauma Surgery, Friedrichsheim, University of Frankfurt, Frankfurt am Main, Germany.
Anticancer Res. 2008 Mar-Apr;28(2A):879-85.
Animal models are indispensable to investigate bone metastasis and to test different preclinical therapy options. Radiofrequency ablation is an upcoming technique for palliating pain from bone metastases. The aim of this study was to generate osteolytic lesions and to enable a technique to achieve access to the bone to successfully carry out radiofrequency ablation.
Human breast cancer cell line MDA-MB-231 (10(5) tumor cells) was implanted into the femur of 10 nude rats using a drill hole after arthrotomy of the knee joint and opening of the femur through the notch. Weekly CT- and MRI-scans were performed to document number and size of bone metastases. Radiofrequency ablation (22G bipolar and impedance-controlled RF-applicator, 2-4 Watt, 3 min application time) was carried out. One week after RFA, the animals were sacrificed and macroscopic and histological examination followed. For statistical analysis, paired comparison procedures were used.
Inoculation of the tumor cells was well tolerated. The mean time of the surgical procedure was 6 minutes. All animals developped local bone metastases. Mean time to metastasis was 8 weeks (range 7-10 weeks) after tumor cell implantation. No leakage of tumor cells and no soft part metastases occurred. Radiofrequency ablation was performed without complications. Imaging showed a complete ablation of the bone tumor in all rats. Histological findings confirmed a circular necrosis with an extensive destruction of tumor cells leaving a necrosis cavity.
The experimental model presented here describes the first time the ability to carry out radiofrequency ablation in nude rats with intrafemoral induced osteolytic metastases of human breast cancer. RFA in human breast cancer cell line in nude rats is a feasible and useful possibility to evaluate and to test different RF-procedures. Additional treatment options like local chemotherapy or chemoembolization can be performed.
动物模型对于研究骨转移以及测试不同的临床前治疗方案不可或缺。射频消融是一种用于缓解骨转移疼痛的新兴技术。本研究的目的是制造溶骨性病变，并实现一种能够进入骨骼以成功进行射频消融的技术。
在膝关节切开术并通过切口打开股骨后，使用钻孔将人乳腺癌细胞系MDA-MB-231（10⁵个肿瘤细胞）植入10只裸鼠的股骨中。每周进行CT和MRI扫描以记录骨转移的数量和大小。进行射频消融（22G双极和阻抗控制射频施加器，2 - 4瓦，施加时间3分钟）。射频消融术后一周，处死动物并进行大体和组织学检查。采用配对比较程序进行统计分析。
肿瘤细胞接种耐受性良好。手术平均时间为6分钟。所有动物均发生局部骨转移。肿瘤细胞植入后转移的平均时间为8周（范围7 - 10周）。未发生肿瘤细胞渗漏和软组织转移。射频消融无并发症发生。影像学显示所有大鼠的骨肿瘤均完全消融。组织学结果证实为圆形坏死，肿瘤细胞广泛破坏，留下坏死腔。
此处呈现的实验模型首次描述了在裸鼠中对人乳腺癌股骨内诱导的溶骨性转移灶进行射频消融的能力。在裸鼠的人乳腺癌细胞系中进行射频消融是评估和测试不同射频程序的一种可行且有用的方法。还可以进行局部化疗或化疗栓塞等其他治疗选择。
