[Surgical treatment for multiple colorectal metastases: efficacy of ablation therapy]

Either hepatic resection, microwave coagulonecrotic therapy (MCN), or a combination of liver resection and MCN was performed in 166 patients with liver metastases from colorectal cancer. In 53 patients who underwent liver resection, the 1-, 3-, and 5-year actual survival rates were 85.0%, 51.2%, and 42.2%, respectively. In 77 who underwent MCN, the 1-, 3-, and 5-year actual survival rates were 82.8%, 46.7%, and 36.0%, respectively. In 34 who underwent both liver resection and MCN, the 1-, 3-, and 5-year actual survival rates were 84.2%, 41.6%, and 21.1%, respectively. The survival rates among the three groups did not differ significantly. Of 166 patients with liver metastases, 44 showed multiple liver metastases (H3). Of 44 patients with multiple liver metastases, 27 underwent MCN (mean tumor diameter 27.2 mm, mean number of tumors 11.2), and the 1-, 3-, and 5-year actual survival rates were 73.1%, 31.3%, and 25.1%, respectively. Of 44 patients with multiple liver metastases, 17 underwent both liver resection and MCN (mean tumor diameter 41.9mm, mean number of tumors 8.1), and the 1-, 3-, and 5-year actual survival rates were 66.3% and 14.7%, respectively. To perform MCN more effectively in the treatment of liver metastases, surgical margins around tumors should be from 10 mm to 15 mm, and both the feeding artery and drainage vein should be coagulated before MCN.