Abstract:

AIM: To analyze the predictive prognostic value of the gross tumor volume (GTV) before chemo-radiotherapy and the tumor volume reduction rate (VRR) after concurrent chemo-radiotherapy (based on PF program) in patients with non-surgical esophageal cancer. METHODS: Clinical data from 77 patients with non-surgical esophageal cancer who under the concurrent chemo-radiotherapy from June 2010 to October 2013 at the First Affiliated Hospital of Fujian Medical University were retrospectively analyzed. Of the 77 patients, 21(27.3%) were at stage T2, 37 (48.0%) at stage T3, and 19 (24.7%) at stageT4; clinical stage II (34, 44.1%), stage III (28, 36.4%), stage IV (15, 19.5%). The tumor length, GTV, and VRR (（pGTV-iGTV）/pGTV) were measured according to CT images before and at the end of chemo-radiotherapy. The Kaplan-Meier method was used to analyze the survival rate. The COX risk regression model was used to analyze the independent predictive value of GTV, VRR, age, gender, T stage, clinical stage, tumor length, pathological type, RT dose and smoking history in the survival rate of non-surgical esophageal cancer who under the concurrent chemo- radiotherapy. RESULTS: The follow-up time ended on September 1st, 2018. The follow-up rate was 94.8% (73/77), of the 73 cases, 64 cases died, and the median survival time was 15 months of the whole group: the 1-year, 3-year and 5-year survival rates were 65.8%, 24.7%,14.8%, respectively; GTV≥25 mL group: of the 35 cases, 32 cases died, the median survival time was 10 months, the 1-year, 3-year and 5-year survival rates were 42.9%,11.4%,8.6%, respectively; GTV<25 mL group: of the 38 cases, 32 deaths. The median survival time was 27 months, and the 1-year, 3-year and 5-year survival rates were 68.4%, 36.8%, 20.3%, respectively; the difference was statistically significant (χ2=9.542, P=0.002); VRR≥0.3 group: of the 41 cases, 33 cases died, the median survival time was 16 months, the 1-year, 3-year and 5-year survival rates were 75.6%, 29.3%,19.5%, respectively. VRR<0.3 group: of the 32 cases, 31 cases died, and the median survival time was 12 months. the 1-year, 3-year and 5-year survival rates were 62.5%,18.8%,7.8%, respectively, and the difference was not statistically significant (χ2=2.419，P=0.120). Univariate analysis by Log-Rank showed: GTV≥25, (HR=2.136, P=0.003), which was related to the prognosis of patients; Multivariate Cox regression analysis showed that VRR（HR=0.309, P=0.001）,GTV (HR=6.557, P=0.000） had an effect on survival and were independent prognostic factors. CONCLUSION: The gross tumor volume (GTV) before chemo-radiotherapy and the tumor volume reduction rate (VRR) are independent factors affecting prognosis. It is recommended to adjust the comprehensive treatment plan according to the GTV and VRR.

Key words: esophageal cancer, concurrent chemo-radiotherapy, gross tumor volume, tumor volume reduction rate, prognosis