ABSTRACT
OBJECTIVE To evaluate the cost-utility of pembrolizumab combined with chemotherapy versus chemotherapy alone in the first-line treatment of advanced or metastatic esophageal carcinoma. METHODS Cost-utility analysis of pembrolizumab combined with chemotherapy versus chemotherapy alone for advanced or metastatic esophageal carcinoma was conducted by using a three-state partitioned survival model from the perspective of health system in China. The model use d a lifetime simulation time frame with 3 weeks as a cycle. The survival data were extrapolated using KEYNOTE- 590 data；cost data were obtained from the median of 2022 public winning bid on Yaozhi network ，among which the price of pembrolizumab was obtained after discounting by a patient assistance program ；utility data were obtained from the literatures ，and a 5％ discount rate was used for both cost and utility. One-way sensitivity analysis and probabilistic sensitivity analysis were also conducted to examine model robustness. RESULTS Analysis of the base case results showed that compared to chemotherapy alone ，the incremental cost-effectiveness ratio （ICER）of pembrolizumab combined with chemotherapy regimens were 950 528.42 yuan/QALY，107 845.39 yuan/QALY and 315 754.56 yuan/QALY for esophageal squamous cell carcinoma （ESCC），programmed deathligand- 1 combined positive score （PD-L1 CPS）≥10 and intention-to-treat population （ITT），respectively. The results of sensitivity analysis verified the robustness of the basic analysis results. CONCLUSIONS Under our healthcare system ，using a threshold of willingness-to-pay of 1-3 times our GDP per capita in 2021，pembrolizumab combined with chemotherapy regimen isn ’t cost-utility compared with chemotherapy alone in the ESCC and ITT subgroups of patients ，while it is cost-utility in the PD-L 1 CPS≥10 subgroup of patients.
ABSTRACT
Metastatic cancer of the esophagus is unusual, Toreson discovered 19 in 599 autopsies on carcinoma patients, an incidence of 3.2%, Most of the patients had primary tumors of the lung, stomach, larynx or breast. Contiguous spread of tumor into the esophagus may produce an ulcerative lesioin resembling primary cancer of the esophagus, as examplified by the direct extension of tumor from the gastric cardia. These tumors may produce esophageal symptoms, notable dysphagia, and present no particular problem to the endoscopist because the ulcerative tumor in the lumen of the eaophagus makes diagnosis easy. Unusuually these tumor will extend into the esophagus submucosally producing submucosal nodules or cicatricial stricture of the esophagus without ulceration inito the lumen. This increases the diagnostic problems because of the difficulty of obtaining a endoscopic biopsy. We experienced a case of multiple nodular metastatic esophageal carcinoma, which was submucosally extended from the stomach cancer, confirmed by endoscopic biopsy. So we report this case with brief review of the previous litera- tures.