Liver metastasis in colorectal cancer: evaluation of segmental distribution

Introduction
It is known that the liver is the main target for metastasis in colorectal cancer. However, we do not know enough from the literature to describe the segmental distribution of liver metastatic lesions of colorectal cancers.

Aim
To investigate which liver segment is affected.

Material and methods
A total of 326 patients (female/male, n = 115/221; age: 53 ±8/51 ±7 years) were included in our study, classified according to their pathological diagnosis. After liver metastases of the patients were determined, they were divided according to Couinaud classification.

Results
While the total number of metastases detected in the right lobe was 691 (70.1%), the number of metastases detected in the left lobe was 294 (29.9%), and the difference was highly significant (p < 0.0001). Metastases in the right lobe anterior segment amounted to 279 (40.4%), and metastasis in right lobe posterior segment was 412 (59.6%), and the difference was significant. When the total number of metastatic lesions is evaluated by excluding segment I, the largest number of lesions were observed in segment VIII. The liver segments with the highest number of metastatic lesions were, respectively, VII, IV, VI, V, III, and II. In this case, the fewest metastatic lesions were observed in segment II.

Conclusions
Liver metastases of colorectal cancer are more common in the right lobe than in the left lobe. The right lobe posterior segment (segment VI) is the main target of metastases.