Prognostic value of the lymph node ratio after resection of periampullary carcinomas.

Background Data have indicated that the lymph node ratio ( LNR) may be a better prognostic indicator than lymph node status in pancreatic cancer. Objectives To analyse the value of the LNR in patients undergoing resection for periampullary carcinomas. Methods A cut off value of 0.2 was assigned to the LNR in accordance with published studies. The impact of histopathological factors including a LNR was analysed using Kaplan- Meier and Cox regression methods. Results In total, 551 patients undergoing a resection ( January 2000 to December 2010) were analysed. The median lymph node yield was 15, and 198 (34%) patients had a LNR > 0.2. In patients with a LNR of > 0.2, the median overall survival ( OS) was 18 versus 33 months in patients with an LNR < 0.2 ( P < 0.001). Univariate analysis demonstrated a LNR > 0.2, T and N stage, vascular or perineural invasion, grade and resection margin status to be significantly associated with OS. On multivariate analysis, only a LNR > 0.2, vascular or perineural invasion and margin positivity remained significant. In N1 disease, a LNR was able to distinguish survival in patients with a similar lymph node burden, and correlated with more aggressive tumour pathological variables. Conclusion A LNR > 0.2, and not lymph note status, is an independent prognostic factor for OS indicating the LNR should be utilized in outcome stratification. [ABSTRACT FROM AUTHOR]