Hepatectomy prolongs survival of mice with induced liver metastases

Resection of hepatic metastases from colorectal cancer has been shown to prolong survival in some patients. Whether this results from a reduction of tumor burden or is an indirect effect mediated by hepatectomy is questionable. Male C57BL/6Ros 8-week-old mice underwent ileocolic vein injection of a suspension of 0.3 mL of 2 x 10(5) viable liver-derived murine (MCA-38) colonic adenocarcinoma cells. This model produces hepatic metastases in all lobes of the liver. At 7, 14, or 21 days after tumor injection, mice were randomized to receive either 42% resection of the liver or laparotomy alone. Survival in the animals with hepatectomy was significantly prolonged when the hepatectomy was performed 14 or 21 days after tumor injection.