A 56-year-old male patient presented with a chief complaint of “abdominal pain for over 1 month.” Physical examination revealed clinical evidence of scleral icterus, indicating the presence of jaundice. Laboratory investigations demonstrated elevated α-amylase levels at 268 U/L (normal reference range: 0–120 U/L), suggesting pancreatic inflammation or ductal obstruction. Tumor marker CA72-4 levels remained within normal limits at 1.15 U/mL (reference range: 0–9.8 U/mL), which is not uncommon in early-stage pancreatic malignancies. This chapter focuses on pancreatic ductal adenocarcinoma (PDAC), presenting 5 distinct cases: PDAC with pseudocyst, with retention cyst, exophytic PDAC, PDAC with hemorrhage, and multiple synchronous PDACs. For each case, it details patient demographics, clinical manifestations, laboratory results, imaging findings (via CT/MRI), pathological examinations (gross, microscopic, immunohistochemistry), and pathological diagnoses. The discussions emphasize differential diagnosis from similar pancreatic lesions, key diagnostic features of each PDAC variant, and the value of multi-modality imaging and histopathology in accurate diagnosis, providing comprehensive clinical references for managing PDAC and its variants.