The Clinical Study On Circumferential Resection Margin Micrometastasis Of Middle And Lower Rectal Cancer

Objective:Rectal cancer is one of the common malignant tumors,its mortality is increasing year by year. Surgical treatment is still the first choice of management for Patients,while there is still some recurrence rate after radical operation. how to reduce local recurrence,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 radical resection. Though following the radical operation,there is still some recurrence rate. The reason was partly due to the disease after surgery is not an accurate clinical and pathological staging, existence of micrometastasis in vivo could not be identified and staging assessment of low. That leading to an unsuitable comprehensive treatment program. If able to carry out accurate staging of these cases, find very small occult metastatic lesions, reduce the transfer rate of misdiagnosis, and use it as a basis for formulating a comprehensive treatment plan after a reasonable, will be markedly improved survival and quality of life.Tumor micrometastasis generally refers to non-hematologic malignancies in the development process, the spread and survival in the lymphatic system, blood circulation, bone marrow, liver, lung and other tissues and organs in the small tumor cell foci, which can be a single tumor cell or an independent foci of tumor cells, no special blood supply to a diameter less than 2mm, often without any clinical manifestations, routine inspection methods such as CT \ MRI and general pathological examination are difficult to find.Postoperative recurrence and metastasis of colorectal cancer is the leading cause of death in patients, in patients with radical surgery, there are still 50% of the patients died of postoperative local tumor recurrence and metastasis, even if the Dukes A phase and B phase colorectal cancer patients ?of postoperative is still a certain rate of recurrence and metastasis, the reason may be related to the existence of early stage colorectal cancer patients with micrometastasis.In recent years, mesorectal circumferential resection margin (circumferential resection margin, CRM) have become an increasing attention, and more and more evidence show that CRM-positive leding to postoperative local recurrence of rectal cancer is an important factor. Pathological slices large organizations can be objectively and accurately observation of rectal cancer CRM situation. Pathological examination of this method can be observed from the whole in the mesorectum of rectal cancer metastasis and tumor location within the primary and the relationship between the rectal wall by this method can accurately observe the surgical margin situation, to determine whether CRM positive. Combined with immunohistochemical techniques, we find that there is circumferential resection margin of tumor micro-metastasis, thereby further enhance the CRM-positive detection rate.This study by HE staining and immunohistochemical pathological combination of large tissue biopsies to explore ways to further enhance the CRM-positive detection rate of clinical cases with 43 cases of combined data and found that the presence of CRM rules to guide clinical treatment.Methods:1.HE staining pathological Large Slice: through the large organizations Slice to observate CRM situation and the relationship between clinical and pathological data, and then analyzed statistically.2. Immunohistochemical staining: The SP method, according to kit instructions to operate, using 1:80,1:80,1:40 diluted mouse anti-human CK20, CEA, Ki-67 monoclonal antibody to detect the cancer system membrane micrometastasis and found that CRM, micrometastases. PBS instead of primary antibody as a negative control. Their results combined with clinical pathological data of the related statistical analysis.Results:1.HE stained histological detection of large sections CRM positive rate was 25.58% (11/43). In which the degree of tumor differentiation, the highly ?differentiated group of CRM positive rate was 0 (0/2), 20.59%(7/34), whereas in poorly differentiated group of CRM positive rate as high as 57.14% (4/7), statistical analysis showed highly differentiated and poorly differentiated group there was significant between group difference was statistically significant (p=0.036<0.05) can be seen as CRM positive rate of poorly differentiated group was higher than high, medium and differentiated group.In the location of the tumor (tumor from the dentate line the lower edge distance) area,≤5cm group of CRM positive rate was 50.00% (7/14) was higher than<5cm group of CRM positive rate of 13.79% (4/29), statistical analysis showed that between the two groups there was significant difference (p =0.035<0.05). In the patient's sex, tumor gross type, surgical approach (laparotomy/ laparoscopy) aspects are related to CRM positive rate was no significant correlation (P>0.05).2.Immunohistochemistry results showed that, CK20, CEA, Ki-67 slice detection of CRM-positive rates were 32.56% (14/43), 30.23% (13/43), 27.91% (12/43). In which the degree of tumor differentiation, the three indicators confirmed that highly differentiated group of CRM positive rate was lower than the poorly differentiated group, statistical analysis there was a significant difference (P<0.05). In the location of the tumor (tumor from the dentate line from the lower edge), the three indicators show<5cm group of CMI was higher than≥5cm group, statistically show that there are significant differences (P<0.05).Three indicators show that patient sex, tumor gross type, lymph node metastasis, surgical approach (laparotomy/laparoscopy) were CRM positive rate with no significant correlation (P>0.05).3.HE staining combined with immunohistochemistry three indicators were detected 20 cases of CRM-positive patients, the positive rate of 46.51% (20/43). HE stain, CK20, CEA, Ki-67 slice detection of CRM-positive rates were 25.58% (11/43), 32.56% (14/43), 30.23% (13/43), 27.91% (12/43), There was no statistically significant pairwise comparison (p = 0.56>0.05).Statistics show HE staining, CK20, CEA, Ki-67 slice joint detection CRM positive rate is higher than any of these detection methods (p = 0.043<0.05). Conclusions:1 CRM-positive patients with postoperative local recurrence is an important risk factor, has been of concern to clinicians.2 large tissue biopsies pathological observation of CRM can be a good situation to be routine postoperative examination.3 HE staining and immunohistochemical CK20, CEA, Ki-67 combined detection of three kinds of indicators for CRM positive rates are higher.4 for the existence of CRM-positive patients, regardless of pathological stage sooner or later, should be postoperative radiotherapy or chemotherapy.5 tumor differentiation, tumor location is the impact of CRM-positive rate of important factors.6 CRM-positive rate and the patient's sex, tumor gross type, surgical approach (laparotomy / laparoscopy) had no obvious relevance.