PS02.182: EFFECTIVENESS OF ANTI-PD-1 ANTIBODY MONOTHERAPY FOR THE PRIMARY MALIGNANT MELANOMA OF THE ESOPHAGUS: A CASE REPORT

Background Primary malignant melanoma of the esophagus (PMME) is extraordinarily rare with a high prevalence of malignancy and poor prognosis, and a standard therapy remains to be established. Since conventional therapeutic methods have been limited in their effects on treatment outcomes, innovative strategies for treating PMME are being explored, especially molecular targeting strategies. The programmed death 1 (PD-1) protein/programmed death ligand-1(PD-L1) inhibitor nivolumab is a promising agent for various cancers. To our knowledge, this is the first case report of PMME where a complete response was achieved using nivolumab. Methods We report an 80-year-old woman who was diagnosed with PMME with bone metastasis and lymph node metastases. Although dacarbazine combined chemotherapy was performed and continued for six cycles, the primary tumor deteriorated and liver metastases appeared. The patient then received nivolumab monotherapy (2 mg/kg, once every three weeks). Results After three cycles, nivolumab monotherapy for PMME resulted in a complete response as shown by positron emission tomography, computed tomography, and esophagogastroduodenoscopy. Conclusion In our case, nivolumab exerted a curative effect on PMME, thus suggesting that nivolumab can be effective in the treatment of this rare disease. Disclosure All authors have declared no conflicts of interest.