Risk factors associated with poor lymph node harvest after colon cancer surgery in a national cohort

Aim Evaluation of ≥ 12 lymph nodes ( LN s) is recommended after surgery for colon cancer. A harvest of ≤ 8 is considered poor, but few reports have evaluated risk factors associated with a poor harvest. This aims of this study were to analyse the clinical, surgical and pathological factors associated with poor LN harvest ( LNH ), the total number of examined nodes and the effect of LN number on stage. Method All patients reported to the N orwegian C olorectal C ancer R egistry during 2007 and 2008 who underwent curative resection for S tage I–III colon cancer were studied. Risk factors for poor LNH and the proportion of Stage III disease were analysed by univariate and multivariate analyses. Results A total of 2879 patients were included in the study. The median LNH was 14. Overall, 69.9% had ≥ 12 lymph nodes and 14.4% had ≤ 8 LN (poor harvest). Multivariate analysis showed that male sex, age > 75 years, sigmoid tumours, pT category 1–2, failure to use the pathology report template and distance of ≤ 5 cm from the bowel resection margin were all independent factors for poor LNH . Age < 65 years, pT category 3–4, and poor tumour differentiation were independent predictors of Stage III disease. An increased LNH did not increase the proportion of patients identified as being LN positive at the ≤ 8, 9–11 and ≥ 12 LN levels. Conclusion Adequate LNH was achieved in the majority of curative colon cancer resections in this national cohort. Elderly, male patients with sigmoid cancers, and a short distal margin were at increased risk of a poor LNH .