Initial Investigation Of Clinical Staging Based On GTV-T Volume Of Esophageal Carcinoma

Esophageal carcinoma is a malignant tumor with high incidence and mortality. Most of patients suffered from advanced stage and bad prognosis. Surgery and radiotherapy are the main treatment methods of esophageal carcinoma. Although the methods in the treatment have made continuously progress, overall 5-year survival is still low. Accurately staging before treatment is an important prerequisite for developing reasonable individual treatment, improving the therapeutic effect and assessment of prognosis. At present, the non-surgical staging methods of esophageal carcinoma are various, and have no unified standards.Pathological staging of esophageal cancer only considered the depth of lesions invasion. It fits patients cured by surgical operation. In addition to the depth of invasion, the tumor size have a direct impact on radiotherapy and chemotherapy treatment to patients who not able for surgery of esophageal cancer. In this study, the relationship between tumor volume and pathological stage and prognosis was explored. Aims to identify the internal rules of pre-treatment staging and provide the basis for assessment of prognosis.Firstly, this study analysis preoperative staging of the 607 cases of radical resection in patients with esophageal cancer used the current clinical staging method. Evaluate the accuracy of the current standards in T stages, N stages and TNM stages compared with postoperative pathological staging. Secondly, transfer preoperative CT image data of this group of patients to the 3D radiotherapy planning system. Outline esophageal tumor GTV-T target, measure the volume of target and analyze (1) whether there are differences of GTV-T volume in different pathologic T stages; (2) relationship between GTV-T volume and survival rate. Finally, look for distribution of GTV-T, plot clinical staging, and develop a new clinical staging program. Re-phase this group of patients under the new program, and evaluate its accuracy and consistency compare with the pathological staging, and the impact on the prognosis for survival. Study factors that influencing survival in patients with cancer of the esophageal after resection by Cox regression model.PartⅠComparison of current clinical staging with pathological staging of esophageal carcinomaObjective:Explore the accuracy and consistency of current clinical staging compare with pathological staging of esophageal cancer, and relationship with prognosis.Methods:Retrospective analysis of 607 cases of radical resection of thoracic esophageal carcinoma in patients with pre-operative CT images and barium esophagogram. Measure and record the maximum diameter of lesion in CT images and the length of lesion in barium esophagogram. Observe and record the invasion of esophageal tumor to the surrounding tissues and organs in CT images (Including whether the tracheal was involved, whether the prevertebral space was disappeared and the angle between lesions and aorta). Observe the situation of supraclavicular, mediastinal and abdominal lymph nodes. Record the cases of other organizations shown in preoperative examination. Plot this group of cases in stages using current clinical staging of esophageal cancer, compare with the pathological staging, and observe the survival of different clinical stages.Results:(1) 30 cases were out of contact among these 607 cases. The follow-up rate was 95.15%. The 1, 3, 5-years survival rates since the surgery date were 83.32%,53.33%,36.02% respectively. The average survival time and median survival time were 42.26 months and 38.33 months. (2) Based on CT images, the diagnosis of tracheal involvement for the accuracy of 90.12%, the sensitivity of 69.33%,the specificity of 92.08%,the positive predictive value of 28.13%,the negative predictive value of 98.53%. Diagnosis of thoracic aorta involvement in CT for the accuracy of 84.84%,the sensitivity of 76.47%,the specificity of 85.08%,the positive predictive value of 12.87%,,the negative predictive value of 99.21%. (3) Divided the largest diameter of esophageal lesions in preoperative CT into three groups:≤2.0cm,2.1cm～3.0cm,>3.0cm. Its 5-year survival rate difference was significant, x2=18.37,P=0.0001. Divided the lesion length in pre-operative barium esophagogram into three groups:≤3.0cm,3.1cm～7.0cm,>7.0cm. Its 5-year survival rate difference was significant, x2=17.02,P=0.0002. (4) The 607 cases clinical T staging of esophageal cancer were concordant with postoperative pathological T staging in 36.41%. Consistency analysis shows that,there was consistency between the clinical T staging and the pathological T staging (P<0.001),but less consistency (Kappa = 0.10). Clinical staging T1, T2, T3, T4 period compared 5-year survival rate were dramatically different (x2=13.34, P=0.004). (5) This esophageal groups clinical N staging were concordant with postoperative pathological N staging in 62.44%,there is consistency between the two (P<0.001, Kappa = 0.30). Clinical staging N0,N1,N2 period compared 5-year survival rate were significantly different (x2=17.94, P=0.0001). (6) The 607 cases clinical TNM staging of esophageal cancer were concordant with postoperative pathological TNM staging in 60.63%,there is consistency between the two (P<0.001, Kappa = 0.29). Clinical stagingⅠ,Ⅱ,Ⅲ,Ⅳperiod compared 5-year survival rate also were dramatically different(x2=22.19, P=0.0001)。Conclusions:(1) The accuracy is higher to determine whether the tracheal and aorta were involved by esophageal lesions based on CT images. (2) After resection of esophageal cancer 5-year survival rate reduces with tumor diameter and length increasing. (3) There was consistency between the preoperative clinical staging and postoperative pathological staging, however, less consistency, subject to further refinement. (4) This clinical staging can better reflect the prognosis of esophageal cancer.PartⅡRelationship among three-dimensional conformal radiotherapy GTV-T size and pathological T staging and prognosis of esophageal carcinoma Objective:To explore whether there are differences of GTV-T volume among different pathologic T stages. Analyze the relationship between GTV-T volume and survival rate. We preliminarily work out the volume of GTV-T standard classification.Methods:The CT scans of 607 cases of esophageal carcinoma can be transmitted to the three-dimensional treatment planning system by the network at digital format. Esophageal GTV-T targets were outlined and their volumes of GTV-T were measured. To analysis that whether there are differences of the GTV-T volume among different pathological T stages. Take into account the average volume of GTV-T in different pathological T stages and the separation of survival curve at the same time. Select a suitable classification standard of GTV-T volume.Results:(1) Esophageal carcinoma GTV-T maximum diameter, length and volume are related to pathological T staging with a positive correlation, Spearman correlation coefficient (r) is 0.466,0.376 and 0.464 respectively,P<0.001. In addition to the maximum diameter, length and volume of GTV-T in pathological T3 and T4 period has no significant difference (P> 0.05), other pathological T stages of these indicators are inter-group significant difference (P<0.001). (2) There is a positive correlation between GTV-T length and maximum diameter of esophageal lesion, r =0.749,P<0.001. (3) Divided the GTV-T volume into there grades:≤5cm3,>5cm3～≤13cm3,>13cm3,compared with pathology T1,T2,T3+4 stage,the coincidence rate is 73.81%. Consistency between the GTV-T volume level and pathology staging is good (P<0.001, Kappa = 0.40). Its 5-year survival rate difference was significant, x2=26.10, P<0.001. (4) Considering the prognosis of survival the volume of GTV-T is divided into four grades:≤5cm3,>5cm3～≤13cm3,>13cm3～≤39cm3,>39cm3. The coincidence rate of GTV-T volume grade and pathology staging is 54.70%,consistency between the two is poor, Kappa = 0.24. The 5-year survival rate compared in different grades was statistically significant, P<0.05. (5) GTV-TⅢandⅣgrading of esophageal cancer has a positive correlation with the number of pathological lymph node metastasis, Spearman correlation coefficient (r) is 0.209 and 0.230,P<0.001. GTV-TⅢandⅣgrading of esophageal cancer has a positive correlation with the number of swollen lymph nodes showed by CT scan, r is 0.155 and 0.209,P<0.001。Conclusions:(1) GTV-T maximum diameter, length and volume has a positive correlation with pathological T staging. In addition to during pathological T3 and T4 stage the average of GTV-T maximum diameter, length and volume has no significant difference, in other pathological T staging groups were significantly different. (2) Divided GTV-T volume into three grades:≤5cm3,>5cm3～≤13cm3,>13cm3,the coincidence rate is good with pathological T1,T2,T3+4 stage,Kappa = 0.40. (3) Divided GTV-T volume into four grades:≤5cm3,>5cm3～≤13cm3,>13cm3～≤39cm3,>39cm3,the coincidence rate is poor with pathological T staging, Kappa = 0.24. (4) GTV-TⅢandⅣgrading of esophageal cancer can better reflect the prognosis of survival. (5) GTV-TⅢandⅣgrading of esophageal cancer has a positive correlation with the number of pathological lymph node metastasis and the number of swollen lymph nodes showed by CT scan.PartⅢRelationship among clinical staging based on GTV-T volume and pathological staging and prognosis of esophageal carcinomaObjective:To explore the coincidence of clinical TNM staging based on GTV-T volume and pathological TNM staging, the relation of clinical staging and prognosis.Methods:The clinical staging standards are formulated according to the volume of GTV-T. Re-phase 607 esophageal carcinoma patients under the new staging program, considering local lymph node metastasis and distant metastasis. The coincidence between new staging and postoperative pathological staging was evaluated. The relation between new staging and prognosis was analyzed.Results:(1) Clinical staging standards based on GTV-T volume:T-staging:T1 GTV-T≤5cm3,T2 5cm339cm3。N-staging:N0 no local lymph node metastasis,N1 had local lymph node metastasis. M-staging:M0 no distant metastasis,M1 had distant metastasis. TNM-staging:ⅠT1N0M0,Ⅱa T2N0M0 / T3N0M0,Ⅱb T1N1M0 / T2N1M0,ⅢT3N1M0 / T4 any N M0,Ⅳany T any N M1. (2) Comparison of clinical staging based on GTV-T with pathological staging: The coincidence of T staging was in partⅡ.,the coincidence rate of N-staging is 66.56%,Kappa = 0.30,P<0.001;the coincidence rate of M-staging is 97.20%,Kappa = 0.55,P<0.001;the coincidence rate of TNM-staging is 62.93%,Kappa = 0.31,P<0.001. (3) 5-year survival rate difference was significant in different T,N,M staging based on GTV-T volume (P<0.05). In GTV-TNM staging, there was no significant difference betweenⅡa andⅡb stage,ⅢandⅣstage of 5-year survival, P>0.05. Significant difference was existent in other stages of 5-year survival, P<0.05. (4) There was no significant difference between pathological T2 and T3 stage of 5-year survival (P = 0.36). Significant difference was existent in other pathological T stages and pathological N staging of 5-year survival. But no significant difference was showed in pathological M staging of 5-year survival (P = 0.097). In postoperative pathological TNM staging, no significant difference was showed betweenⅡb withⅢ/ⅣandⅢwithⅣof 5-year survival,P>0.05. Significant difference was existent in other pathological TNM stages of 5-year survival,P<0.05. (5) The single factor analysis of impact on the prognosis of esophageal cancer showed that the impacting factors are:pathological type, differentiation degree, the length of lesion in barium esophagogram, the maximum diameter of lesion in CT images, pathological T staging, pathological N staging, pathological TNM staging, GTV-T staging, GTV-N staging, GTV-M staging, GTV clinical staging (P<0.05). Cox regression model showed that the independent prognostic factors are: age, lesion region, pathological type, pathological N staging, GTV-T staging (P<0.05).Conclusions:(1) There is coincidence between clinical staging based on GTV-T and postoperative pathological staging of esophageal carcinoma. The consistency of M staging was the best, T staging was better. (2) The clinical staging based on GTV-T staging can better reflect the prognosis of esophageal cancer. GTV-T stage and M stage to determine the prognosis may be better than the pathological T stage and M stage. (3) Cox regression model showed that the independent prognostic factors are age, lesion region, pathological type, pathological N staging, GTV-T staging. (4) The clinical staging based on GTV-T volume of esophageal cancer is a simple and practical staging system based on pathological stage, suitable for clinical application.