Concept of lateral lymph nodes in rectal cancer and controversy over lateral lymph node dissection

Abstract

Lateral lymph node (LLN) metastasis in locally advanced rectal cancer (LARC) is associated with patient prognosis. However, the role of lateral lymph node dissection (LLND) remains controversial. The concept of LLN and the exact definition of LLND have been inconsistently reported in the literatures. The treatment strategy for LARC has differed between the East and the West. The Japanese doctors advocates total mesorectal excision (TME) with LLND for LARC, but less neoadjuvant radiochemotherapy (NARC). European and Americans prefer NARC plus TME, and do not recommend LLND. So far, only the Japanese Statute of Colorectal Cancer has a clear definition of the concept of LLN and LLND. The use of TME plus LLND for LARC is not supported by high level evidences. In today's high-speed development of minimally invasive surgery, the proper selection of standardized surgical methods for LARC requires the joint efforts of scholars from the East and the West to conduct multicenter high-grade clinical trials to select the best treatment option for patients with LARC.