Does Lymph Node Dissection During Esophagectomy Impact the Long-Term Prognosis for Complete Responders After Neoadjuvant Therapy? A Meta-analysis.

BACKGROUND

Neoadjuvant therapy followed by esophagectomy has become the standard of care in locally advanced esophageal cancer. However, the adequacy of lymph node dissection (LND) for patients with a pathologic complete response (pCR) during esophagectomy after neoadjuvant therapy remains undetermined. Our meta-analysis aimed to investigate whether adequate LND was associated with survival benefits in complete responders to neoadjuvant therapy.

METHODS

A systematic online search was conducted to investigate the relationship between the extent of LND and survival in patients with pCR, with overall survival (OS) as the primary endpoint and disease-free survival as the secondary endpoint. Subgroup analyses were performed per LND thresholds, pathology, and geographic regions.

RESULTS

Our study included eight studies involving a total of 2578 patients with pCR. The pooled data demonstrated a significant association between adequacy of LND and improved OS (hazard ratio 0.70; 95% confidence interval 0.58-0.84, p < 0.001). However, no significant survival advantage on disease-free survival was observed (hazard ratio 0.72; 95% confidence interval 0.24-2.20, p = 0.568). Moreover, extensive LND did not bring additional survival benefits to OS when the harvested lymph nodes exceeded 40. Subgroup analyses revealed that adequate LND was significantly associated with superior OS in the Western and adenocarcinoma-predominant populations but not in the Eastern population or in those with squamous cell carcinoma.

CONCLUSION

Adequate lymphadenectomy might correlate with better OS in patients with pCR, specifically in those with adenocarcinoma. Our findings suggested that the extent of LND should be tailored to histology and populations, which should be interpreted with caution.