Background: There is a perception that streamline flow of blood in the portal vein may influence the anatomic distribution of liver metastases, depending on the site of the primary tumor. It has previously been reported that cancers arising in the right colon are distributed to the right lobe of the liver 10 times more commonly than to the left lobe, whereas liver metastases from tumors arising from the left colon and rectum are believed to be distributed homogenously.
Methods: Data were collected prospectively on the anatomic site of hepatic metastases in 207 patients with colorectal metastases referred for consideration for surgery. Anatomic site was established by a combination of computed tomography scanning and either laparoscopic or intraoperative ultrasonography. The site of the primary tumor was known in all cases.
Results: A total of 708 metastases were identified, of which 67% were in the right hemiliver and 33% were in the left. The ratio of involvement of the right and left hemilivers by metastases arising from right colon tumors was 2. 02:1 and for left colon tumors 2.1:1. When patients with unilobar disease only were considered, the ratio of involvement of the right and left hemilivers increased to 2.9:1, but again no difference was evident that depended on the site of the primary tumor.
Conclusions: This study could not find any evidence to support a differential pattern of metastasis within the liver dependent on the location of the primary colorectal carcinoma.
Copyright 2000 American Cancer Society.