Swift Benjamin, Strickland Andrew, West Kevin, Clegg Peter, Cronin Nigel, Lloyd David
Department of Histopathology, Sandringham Building, Leicester Royal Infirmary, Infirmary Square, Leicester, LE1 5WW, UK.
Int J Exp Pathol. 2003 Feb;84(1):17-30. doi: 10.1046/j.1365-2613.2003.00236.x.
Microwave ablation of tumours within the liver may become an adjunct or alternative to resection in patients with primary or secondary cancers. This technique combines the benefits of a large, localized coagulative effect with a single insertion of the applicator, in a significantly shorter time than comparable treatments. A new range of microwave applicators were developed and tested in animal models and both ex-vivo and in-vivo specimens of human liver at resection. At laparotomy, the applicator tip was inserted into normal liver parenchyma and tumours, with each specimen subjected to irradiation for 180 s or more and at varying power outputs. On sectioning an area of spherical blanching was observed around the applicator cavity. Microscopically a zone of coagulative necrosis was seen adjacent to the site of probe insertion. Damage to blood vessels and bile ducts occurred distal to the probe cavity suggesting the passage of heated fluid, a finding that was diminished by temporary occlusion of the hepatic vasculature (a Pringle manoeuvre). Ultra-structural damage was confirmed within the burn zone and selected liver enzymes were shown to be functioning beyond this region. We suggest this indicates the surrounding liver parenchyma is functioning normally and therefore the volume of microwave-induced damage is controllable. We are confident that the new applicator design will allow the effective treatment of larger tumours in a safe and controlled manner with a single application of energy.
对于原发性或继发性癌症患者，肝脏肿瘤的微波消融可能成为肝切除术的辅助治疗方法或替代方法。该技术结合了单次插入施源器即可产生大面积局部凝固效应的优点，且所需时间明显短于同类治疗方法。研发了一系列新型微波施源器，并在动物模型以及人肝切除标本的离体和活体样本中进行了测试。在剖腹手术中，将施源器尖端插入正常肝实质和肿瘤中，每个样本接受180秒或更长时间、不同功率输出的照射。切片时，在施源器腔周围观察到球形变白区域。显微镜下，在探针插入部位附近可见凝固性坏死区。在探针腔远端出现血管和胆管损伤，提示有热流体通过，临时阻断肝血管（普林格尔手法）可减轻这一现象。在烧伤区域内证实存在超微结构损伤，且选定的肝酶在该区域以外仍发挥作用。我们认为，这表明周围肝实质功能正常，因此微波诱导损伤的范围是可控的。我们相信，新的施源器设计将能够通过单次能量施加，以安全、可控的方式有效治疗更大的肿瘤。
