Prognostic value of total number of lymph nodes retrieved differs between left-sided colon cancer and right-sided colon cancer in stage III patients with colon cancer

Abstract

BackgroundThe consensus is that a minimum of 12 lymph nodes should be analyzed at colectomy for colon cancer. However, right colon cancer and left colon cancer have different characteristics, and this threshold value for total number of lymph nodes retrieved may not be universally applicable.MethodsThe data of 63,243 patients with colon cancer treated between 2004 and 2012 were retrieved from the National Cancer Institute’s Surveillance, Epidemiology, and End Results database. Multivariate Cox regression analysis was used to determine the predictive value of total number of lymph nodes for survival after adjusting for lymph nodes ratio. The predictive value in left-sided colon cancer and right-sided colon cancer was compared. The optimal total number of lymph nodes cutoff value for prediction of overall survival was identified using the online tool Cutoff Finder. Survival of patients with high total number of lymph nodes (≥12) and low total number of lymph nodes (< 12) was compared by Kaplan–Meier analysis.ResultsAfter stratifying by lymph nodes ratio status, total number of lymph nodes≥12 remained an independent predictor of survival in the whole cohort and in right-sided colon cancer, but not in left-sided colon cancer. The optimal cutoff value for total number of lymph nodes was determined to be 11. Low total number of lymph nodes (< 11) was associated with significantly poorer survival after adjusting for lymph nodes ratio in all subgroups except in the subgroup with high lymph nodes ratio (0.5–1.0).ConclusionsPrevious reports of the prognostic significance of total number of lymph nodes on node-positive colon cancer were confounded by lymph nodes ratio. The 12-node standard for total number of lymph nodes may not be equally applicable in right-sided colon cancer and left-sided colon cancer.Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4431-5) contains supplementary material, which is available to authorized users.

Current Trends in the Quality Assessment of Colorectal Cancer Practice and Treatment in South Korea during 2012-2017

“…There have been debates about the optimal number of resected lymph nodes in colorectal cancer. There were some studies showing that more lymph node dissection was needed in right hemicolectomy, and others showed that more lymph nodes should be removed if necessary depending on the presence of positive lymph nodes [15][16][17]. Proposing a resection of twelve lymph nodes according to the current guideline may be appropriate in evaluating the quality of treatment and reducing the variability by institution.…”

Association of day of the week with mortality after elective right hemicolectomy for colon cancer: Case analysis from the National Clinical Database

“…Colon and rectal cancers are a worldwide health problem, 12 with right‐sided colon cancer accounting for 30%‐60% of all colon cancers 13–15 . Between 2011 and 2017, the 30‐day postoperative mortality of elective/non‐elective right hemicolectomy was 1.1%‐1.3% while that of low anterior resection was 0.3%‐0.5% in Japan 16 .…”

Prognostic impact of tumour sidedness in patients with stage II colon cancer: a single‐centre retrospective study

“…The reason for this was due to the differences in the extent of the resected area, depending on the tumour location. The right‐sided colon mesentery may anatomically contain a more complex lymphatic system and a larger area of resection, when compared with the left‐sided colon 34,35 . Therefore, the reference value for the number of lymph node dissections may be better considered separately for each tumour location.…”