Clinical Significancy Of Circumferential Resection Margin In The Patients With Middle And Low Rectal Carcinoma

bjective:To analyze the influencing factors of circumferential resection margin (CRM) state and assess the relationship between CRM status and prognosis.Methods:The pathological and clinical data of the 47 patients with middle and low rectal carcinoma who had received total mesorectal excision in our hospital from January 2004 to January 2007,were analyzed.The size of tumor,the shape of tumor,the circumference dimension of penetration in the rectal wall,the distance between the tumor and the anus edge were measured and recorded.The specimens of the rectal carcinoma were immobilizated by 10%formalin for several hours,then,the carcinoma-containing bowels and their mesorectal were cut consecutively in the position which were infiltrated obviously by carcinoma.The specimens were operated into paraffin for imbedding step by step.Slices with tumor and mesorectal were cut by Automated Operator sliding microtome at 5-6μm thickness,to be careful in keeping the completeness of the carcinoma,mesorectum and serosa.The slices were viewed under microscope for the T stag,the differentiation degree,the lymph node state and the CRM status after hematoxylin-eosin staining,and also measured the shortest distance between the tumor and the CRM.the rate of CRM+ were compared with local recurrence,distant recurrence,and the pathological and clinical data by the chi square test,the relation between CRM and the survival of the 47 patients with middle and low rectal carcinoma were analyzed by Kaplan-Meier and Long-rank test.Results:1.Up to now,there were total of 17 patients had died,which included 7 CRM-positive(CRM +) patients and 10 CRM-negative(CRM -) patients.There were 5 patients had local recurrence,4 cases of whom were CRM + and 1 case of whom was CRM -.There were 12 patients developed distant recurrence,5 cases of whom were CRM + and 7 cases were CRM -.2.Kaplan-Meier survival analysis showed the CRM- patients had significantly better survival rate than the CRM+ patients.The two years' survival rate of CRM+ was 41.6%,the two years' survival rate of CRM- was 71.4%.3.The CRM+ had significant relationship with the depth of tumor invasion,tumor size,the circumference dimension of penetration in the rectal wall(d)(P＜0.05 respectively).The positive rate of CRM for T stage was as follow:0%(0/5) for T1,10.5%(2/19) for T2,38.0%(8/21) for T3,100/%(2/2) for T4,this indicated that the state of CRM+ had significant relationship with T stag.The positive rate of CRM for tumor size was as following:15.6%(5/32) for＜5cm,46.7%(7/15) for≥5cm,this also indicated that the rate of CRM+ had significant relationship with tumor size.The rate of CRM for the circumference dimension of penetration in the rectal wall was as follow:0%(0/5) ford＜1/4,15.4%(2/13) for 1/4≤d＜2/4,25%(4/16) for2/4≤d＜3/4,46.2%(6/13) for 3/4≤d＜4/4,this indicated that the rate of CRM+ also had significant relationship with the circumference dimension of penetration in the rectal wall(P＜0.05).The rate of CRM+ had no significant relationship with gender,age,the differentiation degree,the shape of tumor of the patients.Conclusion:1.the rate of CRM+ had significant relationship with the depth of cancer invasion,the size of cancer,the circumference dimension of penetration in the rectal wall.2.CRM status can be used as one of the vital predictor for local recurrence,distant recurrence and two years' survival rate.3.CRM status can be used as one of the reference risk factors for the choice of selective chemotherapy and radiotherapy.