Can lymph node dissection for rectal cancer ever be omitted?

Lymph node dissection is a standard part of surgical resection of rectal cancer which helps to avoid local recurrence and allows for accurate staging of the disease. Three types of lymph node dissection have been considered. Mesorectal lymphadenectomy should remove the mesorectum systematically and should extend at least 5cm distal to the tumor. Inferior mesenteric lymphadenectomy should extend at least to the origin of the left colic artery. Lateral lymphadenectomy removing iliac and obturator nodes results in complications and has not been shown to improve survival; it is not routinely recommended. Omission of lymph node dissection is only proposed for the smallest T1 tumors; with favorable histology.