, Volume 33, Issue 12, pp 2695-2703

Lymph Node Harvest in Colon Cancer: Influence of Microsatellite Instability and Proximal Tumor Location

Purchase on Springer.com

$39.95 / €34.95 / £29.95*

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Background

At least 12 harvested lymph nodes are recommended for proper staging of colon cancer. The effect of tumor-related factors associated with lymph node harvest is not well understood as data are lacking. We investigated tumor-related factors in relation to the number of lymph nodes harvested.

Methods

Patient and tumor characteristics were investigated in relation to harvested lymph nodes (LN ≥ 12), number of metastatic nodes, LN ratio (LNR), and prognosis with univariate and multivariate analyses.

Results

An LN harvest ≥12 nodes was achieved in 36% of the patients. Having <12 nodes harvested was not associated with increased risk for locoregional recurrence, distant metastasis, or decreased survival. Tumor size >5 cm, microsatellite instability (MSI), and proximal tumor location predicted a harvest of LN ≥ 12. The highest rate (54%) of LN ≥ 12 was found for MSI cancers [odds ratio (OR) 2.9, 95% confidence interval (CI) 1.3–6.5; P = 0.011]. Multivariate analysis identified a proximal location as an independent factor of LN ≥ 12 (adjusted OR 3.5, 95% CI 1.5–8.2; P = 0.003), with MSI an independent factor in stage II to III colon cancer (adjusted OR 2.6, 95% CI 1.1–6.0; P = 0.026). To determine the best prognosticator, LNR was the only significant factor in the multivariate analysis (Cox proportional hazards) with a hazard ratio (HR) of 2.9 (95% CI 1.1–7.8; P = 0.038) for LNR 0.01–0.17 and an HR of 5.8 (95% CI 2.5–13.1; P < 0.001).

Conclusions

Proximal tumor location and microsatellite instability are associated with a higher number of lymph nodes harvested, pointing to possible underlying genetic and immunologic mechanisms. The LNR is an independent prognostic variable for colon cancer.