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

Abstract

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; I2 = 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; I2 = 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.

Survival outcomes after synchronous para‐aortic lymph node metastasis in colorectal cancer: A systematic review

“…The extent of PALND is also varied making it difficult to compare outcomes. Previous systematic reviews on this topic have failed to discriminate tumour location (rectal vs. colon) and the ultimate management goal of PALNM 30–32 . Rectal and colon cancer are very different disease entities in terms of the immunological processes, embryological development and ultimate treatment strategy 33–36 .…”

“…These can have a significant impact on postoperative function, but often elude Clavien–Dindo classification. Overall, the majority of evidence suggests that PALND in dedicated units is safe, and the review by Zhao et al supports this too 31 . However, there remains little known on the learning curves, and early experience of new units commencing ‘routine’ PALND.…”

“…Previous systematic reviews on this topic have failed to discriminate tumour location (rectal vs. colon) and the ultimate management goal of PALNM. 30 , 31 , 32 Rectal and colon cancer are very different disease entities in terms of the immunological processes, embryological development and ultimate treatment strategy. 33 , 34 , 35 , 36 In addition, the studies do not have adequate data on the location of PALNM, extent of resection, adverse histopathological details (differentiation, presence of lymphovascular or perineural invasion, tumour budding) and/or molecular subtype details.…”

Management of Surgically Accessible Lymph Nodes Beyond Normal Resection Planes

“…Para-aortic lymph node metastases are rare with a reported incidence from 1% to 6%. [38][39][40] Synchronous isolated metastases are more commonly seen than metachronous with right colon, left colon, and rectal cancer having a synchronous rate of 3.4%, 3.9%, and 3.1%, respectively; whereas metachronous isolated metastases occur 1.0% to 1.3% for colon and rectal cancers. The lower rate for metachronous isolated para-aortic lymph node metastases is likely because they more often occur in combination with distant sites of metastatic recurrence rather than in isolation.…”

“…When the two processes are separated out, retroperitoneal local recurrences have a worse prognosis with a 3-year overall survival and progression-free survival of 27% and 0% compared to 81% and 26% for para-aortic lymph node metastases. 40 This indicates that they should be managed as different disease processes and not as a single entity.…”