对腹膜反折以下cT3或N＋的直肠癌行侧方淋巴结清扫术可减少局部复发率及提高生存率。该术式采用五孔法完成，按日本学组提出的三间隙原则进行清扫：①分离保护输尿管及下腹神经，清扫下腹神经丛及下腹神经与髂总动脉、髂内动脉之间的第二间隙淋巴结；②清扫髂内外动脉间及闭孔内的第三间隙淋巴脂肪组织；③切除髂内血管及盆丛神经。应视肿瘤部位、浸润深度以及侧方淋巴结肿大情况，选择性行单或双侧清扫。腹腔镜下完成侧方淋巴结清扫具有视野好、狭小间隙操作方便、出血少等优势，是一种安全可行的手术方式。

Local recurrence could be decreased and Survival could be improved in patients with cT3 or N+ mid-low rectal cancer by lateral lymph node resection. By using 5-ports method, the surgical procedures could be performed following 3 space dissection principle, firstly total mesorectum excision, then dissection of lymph node between superior hypogastric plexus/hypogastric nerve and common/internal iliac arteries with preservation of autonerve, and last lymph node in the obturator formamen.A selective one side or two sides lateral lymph node dissection should be performed according to the circumferential location of the tumor, depths of tumor invasion and lateral lymph node status. Laparoscopic lateral lymph node dissection bears the benefit of magnified view, and easier manipulation in the narrow space especially in the obturator foramen, which is also a safe and effective procedure.