Lymph node yield following injection of patent blue V dye into colorectal cancer specimens

Aim The study aimed to assess whether the ex vivo injection of patent blue V dye would increase lymph node yield in operative specimens of colorectal cancer. Method A randomized controlled trial was carried out in which patients undergoing resection for colonic cancer were allocated to patent V blue or no patent blue V dye submucosal injection of the operative specimen. The number of lymph nodes found in each group was compared. Results Between 1 January and 31 December 2008, 68 patients were randomized. Thirty‐three patients received patent blue V dye and 34 did not. In the former group the median number of blue nodes identified was 11, compared with a median of 9 in the no dye group. After the application of Carnoy’s solution lymph node count was 16 in each group. There was no significant difference between all these results. Conclusion Ex vivo injection of patent blue V dye submucosally in a peritumour location did not increase the lymph node count or the percentage of specimens having more than 12 lymph nodes identified.