Outcomes of metachronous para-aortic lymphadenectomy in colorectal cancer: a systematic review of the literature.

Introduction And Aim: Para-aortic lymph node metastasis associated with colorectal cancer is a very rare occurrence, but at the same time an important predictor of survival. Despite its importance, there is still no gold standard management strategy, particularly for lymph nodes detected during follow-up, after resection of the primary tumour. Therefore, this review was undertaken to examine the evidence available on the surgical and non-surgical management of metachronous para-aortic lymph node metastasis (m-PALNM) in colorectal cancer treatment.

Methods: This is a systematic review using the patient, intervention, comparison, outcome and study strategy. The literature search was undertaken using Cochrane, MEDLINE, EMBASE and PubMed databases with the following MeSH terms: lymph node excision, para-aortic lymph node, metastasis, metachronous and colorectal neoplasms.

Results: Five original papers met the study criteria including 188 patients in total (55.3% male, 44.7% female). Surgical resection of the m-PALND was the management of choice in 64% of patients. Reporting styles on survival outcomes were heterogeneous. However, patients undergoing surgical management for m-PALNM had longer disease-free survival and overall survival rates.

Conclusion: There is significant paucity in the evidence available on the management of m-PALNM. However, the evidence reported by this review suggests that surgical management should be considered whenever possible, with the aim of prolonging survival. Future randomised trials are needed in order to provide further high-level evidence on m-PALNM management.