Protocol for a multicentre randomized clinical trial comparing oncological outcomes of D2 versus D3 lymph node dissection in colonic cancer (COLD trial)

Abstract

Background The extent of lymph node dissection in colonic cancer surgery remains arguable, and evidence from RCTs regarding extended lymph node dissection outcomes is lacking. This study aimed to compare the long‐term results of D3 lymph node dissection with those of D2 dissection. Methods This is a multicentre RCT. The aim is to enrol 768 patients with primary colonic cancer assigned randomly to D2 or D3 lymph node dissection. The trial is assessing the superiority of 5‐year overall survival as the primary endpoint in patients undergoing D3 lymph node dissection versus D2 dissection. Secondary endpoints include disease‐free survival, short‐term outcomes (30‐day morbidity and mortality), quality of complete mesocolic excision and lymph node dissection, pattern of lymph node metastasis and quality of life in patients following D2 and D3 lymph node dissection. Experience of 20 D3 and 20 D2 lymph node dissections is required for surgeons to participate in the trial. For surgical accreditation four non‐edited videos of procedures will be assessed. Patients will be followed up for 5 years after last patient enrolment. Intention‐to‐treat analysis will be performed. Discussion The results of this study will demonstrate whether extended lymph node dissection is superior to standard dissection in terms of oncological outcomes, and will also assess the impact of more extensive surgery on short‐term outcomes and quality of life.

Pattern of recurrence and survival after D2 right colectomy for cancer: is there place for a routine more extended lymphadenectomy?

“…Currently, two prospective randomized studies, RELARC and COLD, are ongoing and particularly oncologic results are expected to give a more decisive contribution to this pending and controversial issue [ 54 , 57 ].…”

Robotic Complete Mesocolic Excision (CME) is a safe and feasible option for right colonic cancers: short and midterm results from a single-centre experience

“…b Overall survival for robotic CME for colon cancer over standard hemicolectomy. There are a few studies in progress that may provide an answer in the future [23][24][25][26]. Meta-analysis of cohort studies has shown benefit of CME with reduced local recurrence and improved survival [27].…”

The Mesentery in Complete Mesocolic Excision

“…At present, long-term survival/diseasefree recurrence data from these are unavailable. [13][14][15][16] One issue with these trials is that participating surgeons are normally highly skilled in D3 lymphadenectomy, and as such their D2 lymphadenectomies will likely be of a higher standard than that which most people receive. The latter statement is based on the finding (from numerous studies) that significant lengths of the vessels remain in situ post cancer resection (average of 3-4 cm have been reported) and are indicative of a suboptimal D2 lymphadenectomy.…”