Case Report: Immune Checkpoint Inhibitors Successfully Controlled Asymptomatic Brain Metastasis in Esophageal Squamous Cell Carcinoma

BACKGROUND: Brain metastases are the most common cause of intracranial malignancy, often resulting in significant morbidity and mortality. Brain metastases from esophageal squamous cell carcinoma (ESCC) are relatively rare, with a rate of generally less than 2%. CASE REPORT: In this article, we report a rare case of ESCC with asymptomatic brain metastasis. The combined positive score (CPS) of programmed cell death-ligand 1 (PD-L1) from the primary tumor was 2 by DAKO 22C3 and 3 by VENTANA SP263. The proportion of tumor infiltrating lymphocytes (TILs) was 1%. After receiving 15 cycles of immune checkpoint inhibitors (ICIs), the patient’s brain metastatic lesion had disappeared and was replaced by a local necrotic area. He retains good cognitive function with a stable disease at the primary site. CONCLUSIONS: This is the first to be reported in an ESCC patient whose brain metastatic lesion had a complete response to ICIs, which may provide supporting data for using ICIs as an option of treatment for ESCC patients with brain metastases.