Pre-Operative Perihepatic Lymph Node Assessment in Colorectal Cancer Liver Metastasis—A Review of Current Literature

Objective: Perihepatic lymph node involvement in colorectal cancer liver metastases is a negative prognostic factor. Resection of certain nodal stations around the liver has been shown to possibly improve survival. The aim of this review is to interrogate current literature on pre-operative investigations in diagnosing lymph node involvement. Method: A systematic review was conducted of articles published since 2006 to determine usefulness of pre-operative imaging in diagnosing lymph node involvement in colorectal cancer liver metastases. Results: Only 2 papers met the inclusion criteria for this study. Computed tomography (CT) scans were found to have sensitivities of 33% and 40%, specificities of 94% and 92%, positive predictive values (PPV) of 56% and 30%, and negative predictive values (NPV) of 85% and 95%. Positron emission tomography (PET) was studied in one of the paper and was found to have sensitivity, specificity, PPV and NPV of 57%, 100%, 100%, and 88% respectively. Conclusion: There is a significant lack of research on pre-operative investigations of perihepatic lymph node involvement in colorectal cancer liver metastases. Pre-operative CT and PET scans in assessing perihepatic lymph nodes were shown to be inaccurate. Newer pre-operative imaging modalities and research would be needed.