[A Case of Response to Pembrolizumab in Unresectable Recurrent Esophageal Cancer That Relapsed after Nivolumab Therapy].

The patient was a 60-year-old male who underwent subtotal esophagectomy following 3 courses of DCF therapy as preoperative adjuvant chemotherapy for advanced esophageal cancer. The surgery resulted in R2 resection. The postoperative pathology indicated MtUt, CT-pT3, N2(5/26), and pStage ⅢB. The patient received nivolumab and RT(40 Gy)after surgery. After 2 courses of nivolumab therapy, the patient experienced frequent diarrhea and severe dehydration and was admitted to the hospital. CT revealed portal vein gasemia, which necessitated emergency surgery for NOMI. Extensive resection of the small intestine was performed, and the patient survived. The patient was subsequently treated with wPTX as a second-line therapy. After 1 course, the patient developed febrile neutropenia and severe pneumonia, necessitating hospitalization. During this period, the tumor recurred and reached approximately 10 cm in size, exerting pressure on the heart. Pembrolizumab and FP were administered as third-line therapies. After 3 courses, the patient developed irAE colitis, requiring steroid pulse therapy;however, the recurrent tumor shrank significantly, improving the patient's general condition. Follow-up continued without restarting pembrolizumab, and the patient remained relapse-free for 1 year. This case illustrates a successful ICI rechallenge in a patient with advanced esophageal cancer.