Application value of three-dimensional surgery planning system in the preoperative evaluation of primary liver cancer resection

Abstract

Objective To investigate the application value of three-dimensional surgery planning system in the preoperative evaluation of primary liver cancer (PLC) resection. Methods A total of 44 patients with PLC [32 males and 12 females, mean age of (60±12) years old] in Department of General Surgery, Lanzhou University Second Hospital from June 2012 to June 2013 were enrolled in this prospective study. The informed consents of all patients were obtained and the ethics committee approval was received. According to random number table method, the patients were randomly divided into 2 groups: computed tomography angiography (CTA) group and three-dimensional surgery planning (3D) group. Subgroups of complex PLC and non-complex PLC were further defined in each group according to tumor size, tumor invasive extent and history of surgery. In CTA group, 8 cases was assigned in complex PLC subgroup and 14 cases in non-complex PLC subgroup, and 6, 16 cases respectively in 3D group. CTA was used in the preoperative evaluation of PLC resection in CTA group. Liver three-dimensional surgery planning system was used in the preoperative evaluation of PLC resection in 3D group. The intra-operative finding was taken as a gold standard. The visualization of PLC, the adjacent relationship between PLC and peripheral tissues, the display rates of 12 abdominal vessels, variation of hepatic artery, vascular invasion of tumor, cholangiectasis by CTA and three-dimensional surgery planning system were observed. The relationship between estimated tumor volume by three-dimensional surgery planning system and actual weights of resected tumor was analyzed. Non-normal distribution data were expressed in M(Q25,Q75). The display rates by 2 methods were compared using Chi-square or Fisher's exact probability test. The relationship between estimated tumor volume by three-dimensional surgery planning system and actual weights of resected tumor was analyzed using Spearman rank correlation analysis. Results PLC lesions could be both visualized by 2 methods. The adjacent relationship between PLC and peripheral tissues could also be clearly visualized by three-dimensional surgery planning system. For patients with complex PLC, the display rate of abdominal vessels was 81% (78/96) in CTA group, and was 100% (72/72) in 3D group, where significant difference was observed (χ2=15.1, P<0.05). Cholangiectasis could not be visualized in CTA group and the display rate of cholangiectasis was 3/6 in 3D group. For patients with non-complex PLC, the display rate of abdominal vessels was 90% (151/168) in CTA group, and was 100% (192/192) in 3D group, where significant difference was observed (χ2=20.39, P<0.05). Cholangiectasis could not be visualized in CTA group and the display rate of cholangiectasis was 19% (3/16) in 3D group. For patients with complex PLC, the median estimated tumor volume by three-dimensional surgery planning system was 218(129,429)ml and the actual weights of resected tumor was 194(112,429)g, where positive correlation was observed (r =0.943, P<0.05) with an average error rate of 6.5%. For patients with non-complex PLC, the estimated tumor volume by three-dimensional surgery planning system was 368(89,560)ml and the actual weights of resected tumor was 395(126,578)g, where positive correlation was observed (r =0.958, P<0.05) with an average error rate of 6.3%. Conclusions Compared with CTA, three-dimensional surgery planning system can better display the adjacent relationship between tumor and peripheral tissues, abdominal vessels, cholangiectasis and estimate the volume of resected tumor more accurately. It is especially suitable for patients with complex liver cancer. Key words: Tomography, spiral computed; Angiography; Imaging, three-dimensional; Carcinoma, hepatocellular; Hepatectomy