Effect of radical lymphadenectomy in colorectal cancer with para-aortic lymph node metastasis: a systematic review and meta-analysis

Background Colorectal cancer (CRC) with para-aortic lymph node metastasis (PALNM) is an intractable clinical situation, and the role of radical lymphadenectomy in the treatment of CRC with PALNM is still controversial. The aim of the current system review and meta-analysis is to evaluate the clinical efficacy and safety of radical lymphadenectomy in CRC patients with PALAN. Methods We performed a systematic search of PubMed, Embase, Cochrane Library and other online databases up to 31 October 2021. The clinical data including overall survival and postoperative complications were screened and analyzed after data extraction. Odds ratios (ORs) were applied to analyze these dichotomous outcomes with a fixed effects model. Results A total of 7 available retrospective clinical studies involving 327 patients were finally included. CRC patients with PALNM who underwent radical lymphadenectomy showed significantly overall survival (OR: 6.80, 95% CI: 3.46-13.38, P < 0.01; I-2 = 0%) when compared to those who did not receive radical lymphadenectomy. Moreover, in terms of postoperative complications (OR: 0.71, 95% CI: 0.35-1.44, P = 0.48; I-2 = 0%), there was no statistical difference between radical lymphadenectomy treatment and control groups. Conclusions The radical lymphadenectomy treatment has showed the expected clinical efficacy in prolonging overall survival time of CRC patients with PALAN. Moreover, the preemptive radical lymphadenectomy could not cause additional postoperative complications.