P1.127. A Case of Unresectable Advanced Esophageal Cancer Successfully Treated With ICI Regimen and RIC

Abstract

Abstract Topic Esophageal Cancer: Oncology/Radiation Therapy Background Immune checkpoint inhibitors are used for unresectable, advanced, and recurrent esophageal cancer. Currently, the Japan Esophageal Society recommends a 5Fu/CDDP + ICI regimen as first-line treatment. Here, we present a suggestive case of a patient with dysphasia score 4 who had extensive infiltration of the aorta, trachea, and bronchi, in whom an ICI regimen and endoscopic treatment were effective. Methods Case presentation: A woman in her 60s visited our hospital complaining of dysphagia. Upper endoscopy revealed severe circumferential stenosis, primarily in the Mt region. Further examination revealed advanced esophageal cancer with complete stenosis and lymph node metastasis in the cervical, mediastinal, and abdominal regions. Cytology was attempted, but was not performed due to the patient's tendency to bleed. After admission, a PICC was inserted and treatment with 5Fu, cisplatin, and nivolumab was initiated. At the end of the first course, fluoroscopy confirmed contrast passage, and oral semi-digested nutrition was initiated. At the end of the second course, circumferential scarring resulted in complete stenosis, and fluid intake was again impossible. However, endoscopic biopsy revealed no malignant cells. Furthermore, pituitary dysfunction due to irAE was noted, and oral steroids were initiated. Later, irAE-associated nephritis developed, and steroid pulse therapy was initiated. PET-CT and endoscopy confirmed complete response. Results Only two courses of 5Fu + cisplatin + nivolumab therapy were administered, but no further chemotherapy was administered. One year after the initial treatment, endoscopic RIC, radial incision and cutting, was performed. This allowed the patient to eat a normal diet for the first time in a year. One year and three months have now passed, and the patient is still experiencing a complete response. In cases of unresectable disease with a large tumor burden accompanied by complete stenosis and tracheal stenosis, cytotoxic drugs and ICI are the treatment of choice in clinical practice. In this case, the tumor volume was such that no existing normal esophageal tissue could be identified, but RIC was effective in achieving complete scar stenosis after a marked response. Furthermore, with the ICI regimen, we have seen cases where no recurrence has occurred even after treatment completion. Conclusion It may be useful to try RIC in such life-threatening cases in the future if it proves effective, but it is preferable to perform it at a high-volume center with a large amount of experience. We present here examples of multidisciplinary treatment, including the selection of an ICI regimen, treatment for irAEs by multiple medical departments, and RIC, in the treatment of esophageal cancer with a large amount of unresectable advanced tumor, as these are highly suggestive.