Factors Affecting Number of Lymph Nodes Harvested in Colorectal Cancer1

BackgroundLymph node involvement is a highly important prognostic factor in colorectal cancer staging. Examination of a minimum of 12 nodes is recommended for accurate staging. The purpose of this study was to identify factors affecting the number of lymph nodes harvested in colorectal cancer specimens.Materials and MethodsRetrospective review of all patients undergoing colectomy for colorectal cancer at our VA hospital from 2002 to 2007 was done. Statistical analysis was done using univariate as well as multivariate analysis. One hundred eighty-three patients were analyzed.ResultsAverage number of nodes retrieved was 14.9 with 92 (51%) containing fewer than 12 lymph nodes. Median number of nodes was 11. The only two factors found to have an effect on nodes harvested were pathologist P < 0.05 and surgeon experience P = 0.01. Factors not found to have an impact on number of nodes harvested were age of patient, previous operation, T stage of tumor, type of colectomy, bowel prep, laparoscopic versus open technique, or BMI. Multivariate analysis confirmed pathologist and surgeon experience as independent factors associated with number of nodes retrieved P < 0.05.ConclusionsOperating surgeon and examining pathologist were the only factors found to have a significant impact on number of nodes harvested. Meticulous dissection both in and outside of the operating room are indicated.