According to the Global Burden of Disease Study, the number of esophageal cancer cases globally increased from 319,969 in 1990 to 534,563 in 2019, a relative increase of 67.07 per cent. In addition, GLOBOCAN 2020 reported that the global incidence of esophageal cancer climbed to 604,100, accounting for 3.1% of all tumor sites and ranking 7th out of 36 cancers. In addition, the number of global deaths from esophageal cancer increased from 319,332 in 1990 to 498,067 in 2019, a relative increase of 55.97%.GLOBOCAN 2020 reported about 544,076 new esophageal cancer deaths, which accounted for 5.5% of all study centres and ranked 6th among 36 cancers. Chemotherapy is the standard of care for advanced esophageal squamous cell carcinoma, but conventional chemotherapy has limited efficacy, and studies have shown lower median overall survival with chemotherapy in patients with advanced esophageal cancer compared to patients with other stages. In recent years, with the first-line approval of immune checkpoint inhibitors, the treatment of esophageal cancer has entered the immune era. Immune checkpoint inhibitors have become an important therapeutic option for patients with advanced esophageal cancer who have failed chemotherapy. This study will explore the efficacy and safety of this small molecule anti-angiogenic drug, fruquintinib, in combination with tislelizumab in esophageal squamous cell carcinoma previously treated with immune checkpoint inhibitors.