[A Case of Unresectable Thoracic Esophageal Cancer Responding Well to Multimodal Therapy Including 5-FU plus CDDP plus Pembrolizumab].

A 51-year-old male presented with swelling on the left side of his neck. A diagnosis of thoracic esophageal cancer(Lt type 5a, squamous cell carcinoma, T3N4[16LN]M1[skin, bone, retroperitoneum, lung], cStage Ⅳb)was made, and treatment with a combination of 5-FU plus CDDP and pembrolizumab was initiated. After the 1st round of chemotherapy, there was an increase in metastases in the left cervical lymph node and skin, along with the development of back pain because of an L3 lumbar spine metastasis. Palliative radiotherapy(Σ24 Gy/6 Fr)was administered for all lesions. Subsequently, pembrolizumab was administered for the persistent decline in white blood cell and neutrophil counts. After 6 courses of pembrolizumab, computed tomography(CT)revealed an absence of lesions. Positron emission tomography/CT demonstrated no significant accumulation, prompting a diagnosis of complete response(CR). The patient is currently under pembrolizumab therapy and continues to remain in a state of CR.