INTRODUCTION
esophageal cancer, cancer, deaths, esophageal carcinoma
ESOPHAGEAL CANCER, COLORECTAL CANCER, OESOPHAGEAL CANCER, CANCER, METASTATIC ESOPHAGEAL CANCER, ESOPHAGEAL CARCINOMA
The mortality rate of esophageal cancer ranks seventh among all kinds of cancer‐related deaths worldwide.As a result, the use of chemotherapy as the primary treatment has been implemented to enhance the chances of survival for patients with advanced or metastatic esophageal cancer. For advanced esophageal cancer, the primary chemotherapy treatments consist of combining fluorouracil or paclitaxel with platinum.For ESCC, as a stand‐alone treatment for esophageal carcinoma that is resistant to cisplatin and irinotecan, which inhibits topoisomerase I, has demonstrated a total response rate of 15%.Raltitrexed, which is also known as ZD1694 or Tomudex, is a potent and enduring inhibitor of thymidylate synthase (TS). DNA synthesis and repair are highly dependent on the role of TS. Numerous clinical studies have implied an elevation in TS levels in cancerous tissues, which indicates that it plays a potential role in cancer development and advancement. Raltitrexed, a TS inhibitor, which sometimes is a substitute for 5‐Fu, combined with irinotecan is widely recognized that is an effective treatment for colorectal cancer.Sun et al. carried out a prospective study and found that raltitrexed increases radiation sensitivity of ESCC.