Management of para-aortic lymph node metastasis in colorectal patients: A systemic review

Para-aortic lymph node (PALN) involvement occurs in up to 2% of colorectal cancer (CRC) patients. While resection for isolated hepatic and pulmonary metastases in colorectal cancer is standard practice, the role of PALN dissection (PALND) in CRC has not been established and remains a controversy. We aim to perform a systematic review of the literature to determine if extensive lymphadenectomy improves survival, and is an acceptable strategy for PALN metastasis (PALNM).

A systematic search of PubMed and Embase databases for studies reporting on patients with isolated PALNM in CRC was performed. Studies including patients with synchronous and metachronous PALN were included, and studies including patients with other metastases were excluded.

Eighteen retrospective, single-centre studies were included in the final analysis. The reported incidence of isolated PALNM ranged from 1.3 to 1.7%. A total of 370 patients with PALNM were evaluated, of which 145 had synchronous, and 225 had metachronous PALNM. For synchronous PALNM, the 5-year overall survival (OS) after metastatectomy, ranged from 22.7% to 33.9%. For metachronous PALNM, the 5-year OS ranged from 15 to 60%; median OS was 34-40 months in the PALND versus 3-14 months for patients who did not undergo PALND. There were no reported surgery related mortalities, and overall surgical morbidity was 7.8-33%.

PALND for isolated PALNM from colorectal cancer can be performed with minimal morbidity and confers a survival advantage, in comparison with conventional palliative chemotherapy or chemoradiation therapy.