Application Research On Thoracoscopic-laparoscopic Esophagectomy And Circulating Tumor Cells Detection Of Esophageal Cancer

In the past 20 years,the incidence of esophageal cancer has increased.The patients who accepted radically surgery would die because of relapse and distant metastasis.Esophagectomy is still the most important approach for the localized ones.However,it is still a highly invasive operation.Thoracoscopic technology was first reported used for esophagectomy by Cuschieri in the year of 1992 and thoracoscopic surgery excited the interest of the thoracic surgeons.Its safety and feasibility has been proved by several surgeons,and the results of thoracoscopic-laparoscopic esophagectomy were demonstrated never worse than open transthoracic esophagectomy.However,thoracoscopic-laparoscopic esophagectomy was hard to handle because of its wide operation field,complicated adjacent structures and high demand of equipment,it could only be performed step by step.Unexpected conditions or serious complications which would lead to prolonged hospitalization or even death could occur during the development.The thoracoscopic-laparoscopic approach needed a learning curve to improve.We analyzed the clinical data of the patients who accepted thoracoscopic-laparoscopic esophagectomy to discuss the progress of the 4 stages and carried out survival analysis.It clearly showed the learning curve of thoracoscopic-laparoscopic esophagectomy.Then we compared the clinical data of patients who accepted thoracoscopic-laparoscopic esophagectomy and open transthoracic esophagectomy over the same period to find out their own characteristics.Cox proportional hazards analysis was also performed to point out the important factors influencing the survival significantly.All the results could supply the experience and theoretical basis to the development of the approach and the improvement of research teams.It has been demonstrated that,detection of circulating tumor cells(CTCs)in the peripheral circulating blood stream can be a prognostic factor or even supply new strategies for the cancer treatment.Direct and indirect methods have been proposed to detect CTCs,but the results varies in specificity,sensitivity,and cost.Among the direct methods,detection of the CTCs according to the size of the epithelial tumor cells provide good specificity and sensitivity,it also had a good performance in esophageal cancer.The technique of Isolation by Size of Epithelial Tumor Cells(ISET)also has low cost and allows cytomorphological analysis and characterization of CTCs.Although there has been some research on the clinical significance of the CTCs detected among the patients of esophageal squamous cell carcinoma,the ISET is still not widely used and the detection is not closely-related to the surgery or the neoadjuvant therapy.We used ISET technology to isolate CTCs and circulating tumor microemboli(CTM)from the ESCC patients who would accept radical surgery,analyzing the correlation of detection positivity rate and the ordinary clinical data,pathological staging,lymph node metastasis,systemic inflammation,surgery approach,which would provide basis of prognosis prediction or guidance of neoadjuvant therapy.Part ⅠThe learning curve of thoracoscopic-laparoscopic esophagectomy and survival analysis ObjectiveIn the first part,we intended to present the learning curve of the thoracoscopic-laparoscopic esophagectomy via the the clinical evidence and survival analysis,to evaluate the short and medium efficacy of the operation approach.MethodsTo evaluate the development of thoracoscopic-laparoscopic esophagectomy,we studied the bleeding volume,operation time,complication rate,mortality rate within 3 months,the number of lymph node dissection,the proportion of thoracoscopic-laparoscopic Ivor-Lewis esophagectomy.The lymph node dissection and the perform of thoracoscopic-laparoscopic Ivor-Lewis esophagectomy was focused on.The lymph nodes dissected were taken as mean ±SD,and P values were calculated using one-way analysis of variance(ANOVA)with test for equal variances.If heterogeneity of variance existed,we used nonparametric test,which ranked the data first and then performed the one-way ANOVA.Furthermore,lymphadenectomy completeness was also compared as a nominal cutoff(≥12 and 18 lymph nodes)based on published literature values using the chi-square test.Calculate the survival rate using Kaplan-Meier method and draw survival curve.P<0.05 was designated a significant result.ResultsThe bleeding volume of the four periods had significant statistical difference(P=0.0092),there was significant difference between the first and second period(P=0.0263),the later 3 periods had no significant statistical difference(P=0.4625).The operation time had significant statistical difference(P=0.0000),there was significant difference between the first and second periods(P=0.0000),the later 3 stage had no significant statistical difference(P= 0.1107).The mortality rate of the four periods had significant statistical difference(P=0.0092),there was no difference between the first and second period(P=0.0263),significant difference existed between the former two periods and the latter two periods(P=0.005).There was a significant difference on the lymph node dissection among the four periods(P=0.0000);significant difference existed between the former two periods and the latter two periods(13.51±3.25,21.26±7.72,P=0.005).The amount of lymph node resected showed an upward trend.The proportion of thoracoscopic-laparoscopic Ivor-Lewis esophagectomy raised as the number of lymph node dissection raised.There was no significant difference among the 2-year survival rate(72.2%,67.7%,68.01%,P=0.9284)and 2-year disease-free survival rate(66.7%,58.06%,59.6%,P=0.7912)of the the former three periods.ConclusionsThe learning curve of thoracoscopic-laparoscopic esophagectomy was,described as following:bleeding volume would significantly reduce and the operation time would become shorter after the first period(about 20 cases),postoperative mortality within 3 months would significantly reduce after the first and the second period(50-60 cases),and meanwhile,the amount of lymph node dissection increased significantly.The proportion of thoracoscopic-laparoscopic Ivor-Lewis esophagectomy increased after the former three periods,implying the thoracoscopic-laparoscopic approach developed obviously.To strengthen the perioperative management,make sure the resection range and the standardized lymph node dissection was always important.It enhanced to decline the complication rate and the postoperative mortality rate,which was also benefit to survival.Part ⅡClinical Study and Survival Analysis of Thoracoscopic-Laparoscopic Esophagectomy and Open Transthoracic Esophagectomy of the patients with esophageal cancer.ObjectiveIn the second part,we intended to compare the clinical data of thoracoscopic-laparoscopic esophagectomy which had developed to a relatively high level and open transthoracic esophagectomy to present the characteristics and advantages of the two surgical approachs.Perform Cox proportional hazards regression to evaluate the effect of clinical factors on survival to identify the the key factors that affected survival of esophageal cancer.MethodsTo evaluate the advantages and disavantages of the two surgical approachs,we compare the bleeding volume,operation time,complication rate,mortality rate within 3 months,the number of lymph node dissection and the survival rate.Evaluate the clinical factors for survival through Cox proportional hazards regression analysis.Use t test to compare the bleeding volume,operation time,number of lymph node dissection and the stations of lymph node dissection.Use chi-square test to analyze the frequency.Kaplan-Meier method was used to calculate the survival rate and draw the survival curve.Cox proportional hazards regression was used to evaluate the effect of clinical factors on survival.P<0.05 was designated a significant result.ResultsThe bleeding volume of patients who accepted thoracoscopic-laparoscopic esophagectomy was much less than the patients who accepted open transthoracic esophagectomy(P=0.0000).There was significant difference between the two surgical approachs on operation time(P=0.0263),thoracoscopic-laparoscopic esophagectomy cost less.The incidence of respiration system complications after thoracoscopic-laparoscopic esophagectomy was 12.1%,and 29.4%after open transthoracic esophagectomy,the difference was significant(P=0.0000).The number of lymph node dissection was 21.26 ± 7.72 in thoracoscopic-laparoscopic esophagectomy and 23.99 ± 10.15 in open transthoracic esophagectomy,significant difference existed between the two approachs(P=0.0069),but for the stations of lymph nodes harvested,thoracoscopic-laparoscopic esophagectomy accomplished more(P=0.0000).The dissection rate of the recurrent laryngeal nerve lymph node was 78.4%for thoracoscopic-laparoscopic esophagectomy and 23.5%for the open transthoracic esophagectomy(P=0.0000),and the dissection rate of bilateral recurrent laryngeal nerve lymph node for the former approach was 64.7%and only 7.1%for the latter one(P=0.0000).The aortic pulmonary window lymph node obtained more harvest in thoracoscopic-laparoscopic esophagectomy(64.7%vs.7.1%,P=0.0001).However,the dissection of left gastric arteria lymph node dissection was more with 47.1%in the open approach than the thoracoscopic-laparoscopic approach with 12.1%(P=0.0000).Cox proportional hazards regression analysis showed the maximal diameter of tumor cross-sectional area and the number of positive lymph nodes having significant influence on postoperative survival.Conclusions1.Thoracoscopic-laparoscopic esophagectomy could significantly reduce the amount of bleeding volume and the operation time.2.Thoracoscopic-laparoscopic esophagectomy could clean more stations of lymph nodes.The dissection rate was obviously high for the recurrent laryngeal nerve lymph nodes and the aortic pulmonary window lymph nodes,however,left gastric arteria lymph nodes were less dissected with thoracoscopic-laparoscopic approach.3.The maximal diameter of tumor cross-sectional area and the number of positive lymph nodes significantly affected the patients’survival after operation.There was no evidence that thoracoscopic-laparoscopic esophagectomy had different effects on the prognosis of patients with esophageal cancer.Part ⅢCirculating Tumor Cells Detection Study in Patients with Esophageal Squamous Cell Cancer and Its Clinical SignificanceObjectiveIn the third part,we intended to use the ISET(Isolation by Size of Epithelial Tumor Cells)technology to detect CTCs in esophageal squamous cell carcinoma(ESCC)patients before and after surgery to find out the detection positivity rate and its correlation with ordinary clinical data,pathological stage,lymph node metastasis,system inflammatory response,platelet,surgical approach,supplying the evidence for evaluation of state,prognosis and guidance of neoadjuvant therapy.MethodsThis study was granted approval by the ethics committee of the Second Hospital of Shandong University(KYLL-2016(YF)P-0035).Blood samples were obtained from them after we got the informed consent.All the patients enrolled in the study accepted esophagectomy with 2 or 3 field lymph node dissection.55 patients’ blood samples were harvested for CTCs detection.Blood samples from 20 healthy volunteers were used as controls.To evaluate the advantages and disavantages of the two surgical approachs,we compare the bleeding volume,operation time,complication rate,mortality rate within 3 months,the number of lymph node dissection and the survival rate.The cells were recognized as CTCs according to at least four of the following criteria:markedly enlarged nucleus(larger than two to three calibrated pore sizes),high nucleo-cytoplasmic ratio(>0.8),hyperchromasia,irregularity of the nuclear membrane,anisonucleosis(ratio>0.5)and presence of three-dimensional sheets.Cells without cytoplasm were not analyzed in our study.All images were recorded and reviewed independently by 6 cytopathologists from 6 different institutions and the CTCs were confirmed when at least 4 cytopathologists reached an agreement.Part of the samples were performed CD45 confirmination to distinguish CTCs and leucocyte,especially the megakaryocytes or large monocytes.P<0.05 was designated a significant result.The correlation between CTCs detection and clinicopathological parameters,lymph node metastasis,surgical procedure of patients was explored via x2 analysis or Fisher exact test.Student t test was used in the analysis of continuous variables when samples were from population of normal distribution and of homogeneity of variance,or else,two-sample Wilcoxon rank-sum test was used.ResultsThe overall CTCs detection positivity rate was 52.7%pre-operation and 49.1%post-operation.No CTCs were found within healthy volunteers.There was no significant difference of CTCs positivity rate on age,sex,location,size,differentiation,T stage,venous invasion,lymphatic invasion before operation and after operation.For TNM stage,P value was 0.051 before operation,and after combined stage I and II,stage III and IV,there showed a significant difference(P= 0.017).CTCs/CTM was not significantly associated with preoperative neutrophil lymphocyte ratio(NLR),preoperative platelet lymphocyte ratio(PLR)and platelet count.There were no significant difference of the CTCs positivity rate between the lymph node metastasis positive and negative patients no matter before and after the operation.But as for the log odds of positive lymph nodes(LODDS),there was significant difference among LODDS1,LODDS2 and LODDS3 groups(P= 0.033)before operation.The effect on CTCs of thoracoscopic-laparoscopic esophagectomy and open transthoracic esophagectomy showed no significant difference(P=0.864).The number of CTCs or CTM varies a lot when detection was in the similar condition using ISET technology.Conclusions1.CTCs detection positivity rate of esophageal squamous cell carcinoma(ESCC)was high,it correlated with the TNM stage and prognosis.2.CTCs detection-positivity rate correlated with log odds of positive lymph nodes(LODDS).3.Elevated platelet count may promote cancer cell extravasation and raised CTCs in peripheral blood.4.There was no evidence that thoracoscopic-laparoscopic esophagectomy and open transthoracic esophagectomy could have different effect on the level of CTCs.5.We suggested repeated detection of CTCs when considering the count of CTCs especially in the patients with stage III and IV.Whether the average value or the mean value was adopted still needs research.