Clinical study of radiotherapy combined with tegafur bolus synchronization in the treatment of inoperable elderly middle and advanced esophageal cancer.

460 Background: For patients with inoperable oesophageal cancer, simultaneous radiotherapy is the standard treatment option. However, elderly patients are often unable to tolerate CCRT, so a safe, effective and tolerable treatment option is needed. Tegafur, a derivative of 5-FU, has shown efficacy and safety in the treatment of oesophageal cancer. This clinical study evaluated the efficacy and toxicity of radiotherapy combined with a Tegafur bolus in elderly patients with oesophageal cancer. Methods: In this study, 62 patients with unresectable intermediate and advanced ESCC (stage IIA to IVA) between March 2022 and February 2024 were screened and divided into two groups: 32 in the experimental group (simultaneous radiotherapy and chemotherapy) and 30 in the control group (radiotherapy alone). The total radiotherapy dose was 50.4-64 Gy/5.6-6.4 wGy (1.8-2.0 Gy per fraction) in all cases, and the chemotherapy regimen: tegafur bolus (0.5 g, qd/bid, d1-14,q3w) was given from the first day of radiotherapy. The primary endpoint was near-term efficacy, and secondary endpoints included objective remission rate (ORR), disease control rate (DCR), T-cell subpopulation indices, and safety. Results: The CR, PR, SD and PD of radiotherapy combined with tegafur bolus synchronized treatment were 1 (3.1%), 17 (53.2%), 13 (40.6%) and 1 case (3.1%), respectively. The incidence of CR, PR, SD, and PD in the radiotherapy group was 0 (zero), 8 (26.7%), 19 (63.3%), and 3 (10%), respectively. The ORR of the simultaneous radiotherapy group and the control group were 56.3% and 26.7%(P=0.018), and the DCR of the two groups was 96.9% and 90% of the disease control rate of the patients in both groups (P=0.346). The results of univariate analysis showed that the influencing factor of ORR was the treatment regimen (P=0.018), and multivariate logistic regression analysis of variables with P<0.2 showed that the recent efficacy was correlated with the treatment regimen (P=0.039), and that the patients with radiotherapy synchronized with tigafluoroembolization chemotherapy had a better recent efficacy. After treatment, the levels of CD3 + , CD4 + , CD8 + , CD4 + /CD8 + were higher in the synchronized radiotherapy group than before treatment,CD3 + and CD8 + were higher in the control group than before treatment, and CD4 + and CD4 + /CD8 + were lower than before treatment. In terms of adverse reactions, the incidence of acute hematological toxicity (P=1), nausea and vomiting (P=1), radiation esophagitis (P=0.197), radiation pneumonitis (P=0.238), and esophageal fistula (P=0.613) were slightly increased in the simultaneous radiotherapy group compared with the control group. Conclusions: Radiotherapy synchronized with Tegafur suppositories is effective, with relatively mild side effects, convenient and safe for the treatment of inoperable advanced elderly patients with oesophageal cancer. Clinical trial information: ChiCTR2300073845.