The First Case of Primary Malignant Melanoma of the Esophagus to Achieve Pathologic Complete Response after Preoperative Ipilimumab + Nivolumab Followed by Resection

Primary malignant melanoma of the esophagus is a rare disease with a poor prognosis. Surgical resection is common, but there is no consensus on perioperative treatment. Studies have reported the efficacy of programmed cell death-1 inhibitors (e.g., nivolumab, pembrolizumab) and anti-cytotoxic T-lymphocyte-associated antigen 4 agents (e.g., ipilimumab) in treating malignant melanoma. Here, we present the first case of primary malignant melanoma of the esophagus with lymph node metastases treated with nivolumab and ipilimumab followed by resection, achieving a pathologic complete response. A 75-year-old man presented with dysphagia. Esophagogastroduodenoscopy revealed a black, elevated lesion in the mid-thoracic esophagus. Biopsy confirmed primary malignant melanoma of the esophagus, showing tumor cells with melanin deposition, positive for HBM45 and S-100 staining. Computed tomography showed enlarged lymph nodes in the subclavian and mediastinum regions, suggesting metastases. After two courses of preoperative chemotherapy with ipilimumab and nivolumab, which significantly shrank the tumor, the patient underwent robot-assisted subtotal esophagectomy and 3-field lymph node dissection. Histopathological examination revealed no tumors or lymph node metastases, confirming a pathologic complete response. Given the rarity and poor prognosis of primary malignant melanoma of the esophagus, this case provides valuable insights for treatment strategies.