Impact Of The Number Of Lymph Node Examined And Metastasic Lymph Node Rate On Rectal Cancer After Curative Resection

Objective To detect the impact of the number of lymph node examined (NLNE) andmetastasic lymph node rate(LNR) on rectal cancer after curative resection.Methods We conducted a retrospective study of687patients with rectal cancer whohad underwent radical resection from January2002to October2006. The relationshipbetween the number of lymph node examined, the metastasic lymph node rate andsurvival was analyzed.Results The5-year overall survival (OS) of the entire cohort was53.3%. Among allthe cases, there were312patients with lymph nodes negative(LN negative group) and375patients who were lymph nodes positive (LN positive group). The5-year OS rateof the LN negative group and the LN positive group were71.5%and38.1%,respectively. ROC curve analyses showed that NLNE was positive correlation withthe overall survival for rectal cancer (P<0.05) and the cutoff value of NLNE was16.At the T2stage and T3stage of rectal caner, the increased survival was associatedwith increased numbers of lymph node examined（P<0.05）. The LNR is negativerelated to the OS in patients underwent rectal D3resection（P<0.05）. Pearsoncorrelation analysis showed that the LNR was closely related to the number of lymphnode involvement(NLNI)(r=0.859,P=0.000), but unrelated to NLNE (r=-0.034, P=0.516)Conclusion NLNE and LNR both could be the prognostic factor for patients withrectal cancer D3resection. For patients with T2, T3stage, dissection of more than16lymph nodes in the procedure of D3lymphadenectomy for rectal cancer should berecommended so as to evaluate more acurate p-stage, to support the quality of rectalcancer care and then to improve the long term survival rate.