CEACAM5 and neoplasm: After two cycles of chemotherapy with tegafur–gimeracil–oteracil (120 mg/day) + oxaliplatin (100 mg/m2), the recurrent lesion decreased in size to 18 × 9 mm (RECIST: PR; partial response), and tumor marker levels also decreased (CEA: 1.1 ng/mL, CA19-9: 20.3 U/mL).