Regrowth of Isolated Local Residual Tumor Effectively Treated with Chemoradiotherapy More Than Five Years after a Resection for Pancreatic Cancer with an Involvement of the Portal Vein

: A 55-year-old man who presented with abdominal pain was diagnosed with pancreatic head cancer involving the portal vein. He underwent pylorus-preserving pancreaticoduodenectomy without a resection of the portalvein, resulting in a macroscopic residualtumor, because radicalresection was impossible owing to the severe localinvasion. Postoperative chemotherapy( GEM plus S-1)was administered. The tumor size decreased and CA19-9 values normalized. Five years after the resection, chemotherapy was stopped. The regrowth of an isolated local residual tumor without a distant metastasis was diagnosed 65 months after the resection. He underwent chemoradiotherapy(CRT)with S-1. The size of the tumor remained stable, but FDG-PET demonstrated a disappearance of high FDG uptake in the tumor and CA19-9 values normalized. We reported a case in which CRT was an effective treatment for the regrowth of localresidualtumor after resection for pancreatic cancer.