Introduction Increased numbers of lymph nodes (LN) retrieved within a colorectal cancer resection is positively associated with survival and as such, identification of ≥12 LN is considered to be a surgical quality indicator. Here we audited LN retrieval data to establish both quality compliance and identify factors affecting identification rates.

Method All colorectal cancer resections from April 2012–October 2014 at our institution were identified from the hospital’s cancer registry. The primary outcome variable was the number of nodes identified within the resection.

Results 398 cases were included with a median LN retrieval number of 16. Greater numbers of nodes were identified in laparoscopic versus open surgery (p < 0.05), high versus low T stage (p < 0.005) and by trainee versus consultant pathologists (p < 0.005). Whilst higher lymph node numbers were associated with a higher nodal positivity rate, there was no evidence that this caused stage migration. Regression analysis identified pathologist grade, T stage and number of positive nodes as independent predictors of high LN yield.

Conclusion Local compliance in the identification of ≥12 nodes was achieved. Audit analysis of LN retrieval data provides insight into the biology of colorectal cancer as well as identifying institutional specific predictors of LN yield.

Disclosure of interest None Declared.

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