BACKGROUND The method of management of patients with multiple liver metastases is controversial. OBJECTIVE To review 10 years of experience gained in a tertiary referral hepatobiliary unit in managing multiple liver metastases from colorectal cancer. DESIGN AND INTERVENTION This was a retrospective review of a prospectively collected data set from patients who underwent resection for colorectal liver metastases at a single specialist center in the UK from 1993 to 2003. No ablative therapy was performed. To be accepted for treatment, patients were required to be fit for major surgery, and lack disseminated or nonresectable extrahepatic disease according to CT and MRI scans. The extent of resection performed was decided on the basis of the location and number of metastases, because underlying chronic hepatic disease was not usually present. Patients were permitted adjuvant therapy with fluorouracil and calcium folinate, unless they had received adjuvant therapy within the year previous to surgery. Patients received a minimum of 2 years' follow-up at specialist clinics (range 2-12 years; median 33 months for survivors). OUTCOME MEASURES The end points of the trial were overall and disease-free survival, morbidity and mortality, and length of postoperative hospital stay. RESULTS In all, 484 patients were included in the analysis (mean age 62 years; range 23-84 years), and 225 had synchronous disease. The number of liver metastases per patient ranged from 1 to 21 (median 2). Multiple (>= 4) metastases were present in 136 patients, of whom 36 had numerous (>= 8) metastases. Individual metastatic deposits ranged in size from 3mm to 200mm (median 40mm). Complete resection was achieved in 67% of patients. Postoperative hospital stay ranged from 3 days to 139 days (median 8 days). The in-hospital mortality rate was 3%; all the deaths were in patients who had undergone major resection. There was a postoperative morbidity rate of 26%. For the whole group, 5-year and 10-year survival rates were 41.7% and 28.6%, respectively. Median survival was 50 months for patients with fewer than 4 metastases, but was 32 months for patients with multiple metastases (P=0.0072). Survival differences between patients with fewer than 4 metastases and those with multiple metastases were not significant. Patients with multiple metastases had poorer disease-free survival than those with fewer than 4 metastases (P=0.0142). Patients with numerous metastases had the worst survival outcome (5-year survival rate 24.2%; median survival 21 months, 95% Cl 15-27 months; P=0.0245 for >= 8 tumors in comparison with 4-7 tumors). On multivariate analysis, only the presence of numerous (8 or more) metastases predicted for poorer overall (P=0.047) and disease-free (P=0.015) survival. There was also an association between increasing number of metastases and worsening intrahepatic recurrence, with 74% of patients with numerous metastases having intrahepatic disease (P<0.001 vs both patients with <4 metastases and those with 4-7 metastases). CONCLUSION Significant numbers of patients who receive surgery for multiple metastases survive for 5 years or longer; therefore, resection is recommended for such patients.
