Surgical Procedure of Lateral Lymph Node Dissection for Advanced Lower Rectal Cancer

Lateral lymph node dissection (LLND) is recognized as an effective treatment for reducing local recurrence in patients with locally advanced lower rectal cancer. However, the lack of standardization in techniques and anatomical landmarks remains a concern, as it may complicate the assessment of treatment efficacy. To address this, the Japan Society of Gastroenterological Surgery (JSGS) held a consensus meeting during the 77th General Meeting of the JSGS to standardize LLND techniques. In this meeting, essential anatomical landmarks for LLND were confirmed. The primary regions targeted for dissection include lymph nodes in the obturator region (designated as station 283) and those in the internal iliac region (designated as station 263). The medial boundary of LLND is defined by the uretero-hypogastric fascia, whereas the vesico-hypogastric fascia constitutes the central plane of dissection and serves as the medial boundary of station 283. Indicators of successful LLND completion include exposure of the sciatic nerve (lumbosacral trunk) at the bottom of the dissection, as well as exposure of the inferior vesical vessels, internal pudendal artery, and coccygeus muscle, confirming the thoroughness of the caudal part of the dissection. The consensus reached in this meeting, along with findings from several published reports cited in this report, is expected to contribute to the standardization of LLND quality.