Schaefer Nico, Schafer Hartmut, Maintz David, Wagner Mathias, Overhaus Marcus, Hoelscher Arnulf H, Türler Andreas
Department of Surgery, University of Bonn, Bonn, Germany.
J Surg Res. 2008 May 15;146(2):230-40. doi: 10.1016/j.jss.2007.03.084. Epub 2007 Aug 8.
Local antitumoral therapy of metastases is an important tool in the palliative treatment of advanced colorectal cancer. Several authors have recently reported on successful local treatment of different malignant diseases with low-level direct current therapy. The aim of the present study was to compare the effectiveness of direct current therapy with the established laser-induced thermotherapy (LITT) on experimental colorectal liver metastases.
Colorectal metastases were induced in 49 BD IX rats by injection of colon cancer cells beneath the liver capsule. Three weeks after induction, tumor volumes and sizes were estimated with magnetic resonance imaging and by manual measurement of the largest tumor diameter, and two treatment groups and two control groups were established. Direct current (80 C/cm(3)) versus LITT (2 W; 5 to 10 min) was locally applied via laparotomy. Control groups were sham treated. Tumor growth was analyzed 5 wk after therapy by manual measurement of the maximal diameter and histopathological examination was performed.
Measurement of tumor sizes 5 wk after therapy confirmed a significant antitumoral effect of direct current (1.6-fold tumor enlargement) and of LITT (1.3-fold tumor enlargement), compared with controls (2.8-fold and 2.9-fold tumor enlargement). However, after 5 wk, LITT was significantly more effective in limiting tumor growth than direct current treatment (P </= 0,001). Histopathological analysis revealed a complete response rate of 21% and a partial response rate of 77% in the electric current group. In comparison, LITT treated livers showed a complete response rate of 22% and a partial response rate of 78% (n.s.).
The data confirm that direct current therapy and LITT are effective treatment strategies in the palliative control of colorectal hepatic metastases, with both therapies being equally effective in inducing a complete or partial tumor necrosis.
转移瘤的局部抗肿瘤治疗是晚期结直肠癌姑息治疗的重要手段。最近有几位作者报道了低强度直流电疗法成功地对不同恶性疾病进行局部治疗。本研究的目的是比较直流电疗法与既定的激光诱导热疗（LITT）对实验性结直肠癌肝转移的疗效。
通过将结肠癌细胞注射到49只BD IX大鼠的肝包膜下诱导产生结直肠癌转移瘤。诱导后三周，用磁共振成像和手动测量最大肿瘤直径来估计肿瘤体积和大小，并建立两个治疗组和两个对照组。通过剖腹术局部应用直流电（80 C/cm³）与LITT（2 W；5至10分钟）。对照组进行假治疗。治疗5周后通过手动测量最大直径分析肿瘤生长情况，并进行组织病理学检查。
治疗5周后肿瘤大小的测量证实，与对照组（肿瘤增大2.8倍和2.9倍）相比，直流电疗法（肿瘤增大1.6倍）和LITT（肿瘤增大1.3倍）具有显著的抗肿瘤作用。然而，5周后，LITT在限制肿瘤生长方面比直流电治疗显著更有效（P≤0.001）。组织病理学分析显示电流组的完全缓解率为21%，部分缓解率为77%。相比之下，接受LITT治疗的肝脏的完全缓解率为22%，部分缓解率为78%（无显著性差异）。
数据证实直流电疗法和LITT是姑息性控制结直肠癌肝转移的有效治疗策略，两种疗法在诱导完全或部分肿瘤坏死方面同样有效。
