The management of clinically suspicious para-aortic lymph node metastasis in colorectal cancer: A systematic review

Approximately 1%-2% of patients with colorectal cancer (CRC) develop para-aortic lymph node (PALN) metastases, which are typically considered markers of systemic disease, and are associated with a poor prognosis. The utility of PALN dissection (PALND) in patients with CRC is of ongoing debate and only small-scale retrospective studies have been published on this topic to date. This systematic review aimed to determine the utility of resecting PALN metastases with the primary outcome measure being the difference in survival outcomes following either surgical resection or non-resection of these metastases. A comprehensive systematic search was undertaken to identify all English-language papers on PALND in the PubMed, Medline, and Google Scholar databases. The search results identified a total of 12 eligible studies for analysis. All studies were either retrospective cohort studies or case series. In this systematic review, PALND was found to be associated with a survival benefit when compared to non-resection. Metachronous PALND was found to be associated with better overall survival as compared to synchronous PALND, and the number of PALN metastases (2 or fewer) and a pre-operative carcinoembryonic antigen level of <5 was found to be associated with a better prognosis. No PALND-specific complications were identified in this review. A large-scale prospective study needs to be conducted to definitively determine the utility of PALND. For the present, PALND should be considered within a multidisciplinary approach for patients with CRC, in conjunction with already established treatment regimens.