Radiofrequency thermal ablation of synchronous metastatic liver tumors canbe performed safely in conjunction with colorectal cancer resection

PURPOSE Only 10% to 20% of patients with metastatic liver tumors from colorectal ca ncer have resectable tumors. Radiofrequency thermal ablation (RFA) has been recently investigated as a new nonresectional ablation method. Some of the advantages of RFA over hepatic resection are its minimal invasiveness and its lower rate of complications. We have used RFA for synchronous unresecta ble metastatic liver tumors in conjunction with primary colorectal cancer r esection and have investigated the safety and efficacy of this combined pro cedure. PATIENTS AND METHODS Since August 1997, 84 operations for RFA were performed in 62 patients with malignant primary and metastatic liver tumors. In nine of these patients, RFA was performed for synchronous liver tumors simultaneously with primary colorectal cancer resection. In each operation, after surgical exploration, intraoperative ultrasound was performed. RFA was guided by intraoperative ultrasound and temperature monitoring. RESULTS Nine patients had unresectable metastatic liver tumors at the time of color ectal resection. A total of 37 tumors were treated. The number of liver tum ors in each patient ranged from one to nine (mean, 4.1), and the tumor size ranged from 7 to 70 mm (mean, 36 mm). Intraoperative ultrasound identified six occult tumors (16.2% of 37 tumors) in five patients (55.5% of nine pat ients). Colorectal resection and RFA were completed without intraoperative complications. The ablation time ranged from 12 to 248 minutes (mean, 100 m inutes). There were minor early postoperative complications in two patients . There was one late postoperative complication, a bile duct structure, whi ch required biliary stent placement. The length of hospital stay was 5 to 1 5 days (mean, 8.6 days). After surgery, carcinoembryonic antigen level decr eased in all patients (mean reduction, 91.3%). During a mean follow-up of 1 2.6 months, local tumor recurrence at the RFA site (caused by treatment fai lure) occurred in two tumors (5.4% of 37 tumors) in two patients (22.2% of nine patients). Five patients (55.5%) had other areas of intrahepatic or ex trahepatic recurrence of cancer. DISCUSSION With the use of intraoperative ultrasound, RFA of liver tumors can be perfo rmed safely during laparotomy for primary colorectal cancer resection. RFA is effective in locally controlling unresectable liver tumors with low loca l tumor recurrence. RFA may become an optimal modality for the treatment of synchronous metastatic liver tumors and can be performed safely in conjunc tion with colorectal cancer resection.