Clinical Research On Circumferential Margin Involvement Of Middle And Lower Rectal Cancer

ObjectiveRectal cancer is one of the common malignant tumors,its incidence and mortality are still high.Surgical treatment is still the first choice of management for Patients.with the development of surgery,molecularbiology and immunology etc,Surgical treatment also have great development.how to reduce local recurrence ulteriorly,improve PostoPerative life quality,at the same time,ensure the effect of surgical treatment,become a hot question .Widely introduction of total mesorectal exeision(TME) had significantly reduce local recurrence following the curative resection.beforetime,people attached importance to the distal clearance margin and had done many research,defined a safe distal clearance margin.currently,people pay more attention to the circumferential margin involvement,and more and more researches had proved that circumferential margin involvement was a important factor of local recurrence after the curative rese- ction.Researches of circumferential margin involvement is a key of reducing the local recurrence.Pathologic large slice can observe circumferential margin involvement distinctly.it can observe holistic mesorectal,the orientation of metastasis,and make sure the relation of metastasis and the primary affection.this method can accurately find circumferential margin involvement,combine with immunohistochemical technique,it can find micrometastasis in circumferential resection margin,enhance the check-up rates of circumferential margin involvement.This study combined pathologic large slice and Immun- ohistochemical technique to discuss how to enhance the check-up rates of circumferential margin involvement,and studied 41 patients'clinicopathlogic characteridtion,detected the rule of circumferential margin involvement,and leaded a reasonable clinical treatment.Methods1.Pathologic large slice with hematoxylin and eosin:we used this method to detect the relationship between circumferential margin involvement and clincopathologic features,then analyzed the results.2.Immunohistochemistry was performed by using the SP method. We used mouse anti-CK20 (1:80 dilution), mouse anti-CDX2 (1:80 dilution),mouse anti-MMP7 (1:40 dilution) to detect circumferential margin involvement in samples, then analyzed the results with the clincopathologic features .Results9 patients (21.95%) with positive circumferential resection margin were detected by pathologic large slice with hematoxylin and eosin.On differentiation of tumour,60.7% poorly differentiated specimens were detected circumferential margin involvement,while moderate and well-differentiated cancer specimens were only 8.00% and 16.7% respectively (P=0. 004<0.05).About station of tumour,positive circumferential resection margin was more frequent in<5cm specimens (46.15%),compared with≥5cm specimens(10.71%)(P=0.003 <0.05).About different operation mode(Miles/Dixon), positive circumferential resection margin was more frequent in Miles specimens(46.15%),Compared with Dixon specimens(10.71%) (P=0.003<0.05).No significant correlations were found between circumferential resection margin and other clincopathologic features,such as gender,age,tumor invasion,lymph node metast- asis,pathology general classification,operation method (P>0.05).By immunohistochemistry analysis on samples,CK20, CDX2,MMP7 detect positive circumferential resection margin 29.27%(12/41),31.71%(13/41),26.83%(11/41) respectively. About differentiation of tumour,three antibodies proved that positive circumferential resection margin was more frequent in poorly differentiated specimens than moderate and well-differentiated specimens(P<0.05).About station of tumour,three antibodies proved that positive circumferential resection margin was more frequent in<5cm specimens than in≥5cm specimens (P<0.05).CK20 and CDX2 proved that no significant correlations were found between circumferential resection margin and other clincopathologic features,such as gender,age, tumor invasion,lymph node metastasis,pathology general classi- fication,operation method(P>0.05).But about lymph node metastasisand, MMP7 prove that 8.70% N0 lymph node metastasis specimens were detected circumferential margin involvement, while N1 and N2 lymph node metastasis specimens were 46.15% and 6.00% respectively (P=0. 009).15 patients (36.59%) with positive circumferential resection margin were detect by combining pathologic large slice and im-munohistochemical technique.large slice with H-E,CK20,CDX2, MMP7 detected positive circumferential resection margin 21.95%,29.27%(12/41),31.71%(13/41),26.83%(11/41) respectively.There were no significant difference between each other (P>0.05).Combining pathologic large slice and immunohistochemical technique could get more positive circumferential resection margin than single method or sigle antibody(P<0.05)Conclusions1 Pathologic large slice can observe circumferential margin involvement distinctly.It should be a routine examination following the curative resection.2 Combining pathologic large slice and immunohistoch- emical technique could get more positive circumferential resection margin.3 Whether TNM stage is early or not,the patient who have positive circumferential resection margin should get normally postoperative adjuvant therapy. 4 Circumferential resection margin of middle and rectal cancer has significant correlation with tumor differentiation, tumor station,lymph node metastasis,different operation mode (Miles/Dixon).5 Circumferential resection margin of middle and rectal cancer has no significant correlation with gender,age,tumor invasion,pathology general classification,operation method.