Successful conversion surgery following chemotherapy with an immune checkpoint inhibitor in an older adult patient with stage IVB esophageal squamous cell carcinoma: a case report

BACKGROUND: Chemotherapy and chemoradiotherapy are common treatments for esophageal squamous cell carcinoma with distant metastasis; however, the prognosis remains poor, and complete remission is difficult to achieve. Here, we report a case of an older adult patient with esophageal squamous cell carcinoma who underwent surgery following combined treatment of immunotherapy and chemotherapy and achieved pathological complete response. CASE PRESENTATION: An 80-year-old woman presenting with difficulty swallowing was referred to our hospital. She was diagnosed with esophageal squamous cell carcinoma with distant metastasis of the lymph node at the dorsal side of the IVC and the left supraclavicular lymph node. She was treated with pembrolizumab, cisplatin, and 5-fluorouracil. After four pharmacotherapy courses, primary tumor and metastatic lymph node shrinkage was observed. The patient underwent thoracoscopic subtotal esophagectomy and regional lymph node dissection. The lymph node at the dorsal side of the IVC was not resected, and the left supraclavicular lymph node was removed. Histological examination revealed complete response with no residual tumor or lymph node metastasis. The patient had no recurrence 10 months postoperatively without adjuvant chemotherapy. CONCLUSIONS: Conversion surgery following preoperative therapy, including immunotherapy, may be an effective treatment strategy for improving survival in patients with esophageal squamous cell carcinoma even among older adult patients.