Intracellular expression of MAGE-A4 has been observed in several tumor types (5, 6), with ≥20% prevalence reported in synovial sarcoma and myxoid/round cell liposarcoma, bladder urothelial carcinoma, gastric cancer, ovarian carcinoma, esophageal cancer, and head and neck squamous cell carcinoma (HNSCC) (6). This evidence concerns the gene MAGEA4 and esophageal cancer.