Extended lymphadenectomy in locally advanced rectal cancers: a systematic review

PURPOSE: The surgical treatment of advanced low rectal cancer remains controversial. Extended lymphadenectomy (EL) is the preferred option in the East, especially in Japan, while neoadjuvant radiotherapy is the treatment of choice in the West. This review was undertaken to review available evidence supporting each of the therapies. METHODS: All studies looking at EL were included in this review. A comprehensive search was conducted as per PRISMA guidelines. Primary outcome was defined as 5-year overall survival, with secondary outcomes including 3-year overall survival, 3- and 5-year disease-free survival, length of operation, and number of complications. RESULTS: Thirty-one studies met the inclusion criteria. There was no significant publication bias. There was statistically significant difference in 5-year survival for patient who underwent EL (odds ratio, 1.34; 95 confidence interval, 0.09–0.5; P=0.006). There were no differences noted in secondary outcomes except for length of the operations. CONCLUSION: There is evidence supporting EL in rectal cancer; however, it is difficult to interpret and not easily transferable to a Western population. Further research is necessary on this important topic.