The Extracapsular Lymph Node Extension Predicts Outcomes in Colorectal Cancer: A Short Review

The extension of the metastatic lymph nodes through the capsule to the adipose tissue in the perinodal or extra-nodal defines the extra-nodal extension (ENE). ENE represents an important prognostic factor in multiple cancers, which is considered as a prognostic parameter in different tumor-node-metastasis (TNM) classifications.Colorectal cancer (CRC) is ranked third in order of frequency, after successively lung and breast cancer. Lymph node metastasis has been validated as a significant negative prognostic factor for survival in colorectal cancer (CRC), which is improved by the adjuvant. Despite the use of ENE as an important and validated prognostic factor in multiple cancers, ENE is not yet taken into account in the CCR staging system.The present short review aims to discuss the prognostic impact of ENE on CRC according to the emerging evidence. To conduct this study, we have reported the results of all available studies following the scientific rationale in three parts: retrospective studies, prospective studies, and meta-analyses.ENE has a negative impact on the prognosis of colorectal cancer but is not yet used in practice in colorectal cancer.We, therefore, propose to carry out randomized clinical trials to study this subject better and strengthen its value in management strategies.