Lateral lymph node dissection in rectal cancer patients: is there any indication?

Excerpt

It is accepted that optimal therapy for middle and low rectal cancer should consist of a perfect total mesorectal excision (TME) and preoperative long-term radio-chemotherapy when infiltration of surrounding organs (T4) is diagnosed. In the Western world the discussion focus on the questions of whether advanced T3 carcinomas less than 5 mm from the fascia pelvica visceralis should undergo neoadjuvant radio-chemotherapy such as T4 tumors, and which patients would benefit from short-term neoadjuvant radiation or from adjuvant radio-chemotherapy. For several decades mostly Japanese surgeons have promoted lateral lymph node dissection along the common and internal iliac artery particularly in patients with advanced extraperitoneal rectal carcinoma. In the International Journal of Colorectal Disease Koda et al. [1] present data from 452 patients with middle and low rectal cancer operated on between 1984 and 2000: 265 undergoing lateral lymph node dissection and 155 long-term neoadjuvant radio-chemotherapy. They found lateral lymph node metastases in 7.7% of their patients, ranging from 0% (0/44) pT2 middle rectum tumors to 18.8% (3/16) pT4 lower rectum carcinomas. Prior to the introduction of TME lateral lymph node dissection alone did not improve survival rates. The combination of neoadjuvant radio-chemotherapy with lateral lymph node dissection improved 5-year overall survival rates from 48% in patients treated without either to 74% for extraperitoneal pT3/pT4 cancers. Including TME in the surgical concept improved local recurrence rate with and without lateral lymph node dissection. The authors conclude that in T2 cancer lateral lymph node dissection is not beneficial and that in extraperitoneal pT3/4 tumors, which are associated with a higher incidence of lateral node metastases, lateral node dissection or neoadjuvant radio-chemothreapy may be reasonable procedures, performed in addition to TME. …