Pancreatic cancer is often diagnosed at advanced stage, where chemotherapy is the mainstay of treatment. Despite new chemotherapy regimens improving overall survival over the past decade, the median survival for advanced pancreatic cancer remains around one year. However, we occasionally encounter long-term survivors among patients with advanced pancreatic cancer. Analyzing these cases may provide valuable insights for understanding pancreatic cancer and improving treatment strategies. We report a case of 61-year-old patient with metastatic pancreatic cancer who survived for approximately five years. Single-cell transcriptome analysis of tissues obtained at the time of pancreatic cancer diagnosis and at 57 months post-diagnosis revealed changes in the tumor immune microenvironment.