Undifferentiated carcinoma with osteoclast-like giant cells of pancreas: A case report with review of the computed tomography findings

RATIONALE: Undifferentiated carcinoma with osteoclast-like giant cells (UC-OGCs) of the pancreas is an extremely rare and aggressive pancreatic malignancy. To our knowledge, the computed tomography (CT) findings of this disease have rarely been analyzed. PATIENT CONCERNS: A 65-year-old man who experienced weight loss of about 4 kg over 3 months presented to our clinic. The abdominal ultrasound (US) detected a 5.8 × 5.5 cm well-defined, cystic-solid mass in the head of the pancreas, which had been present for 1 month. DIAGNOSIS: A benign pancreatic tumor was initially suspected on the basis of the US findings. The patient then received serum tumor markers and CT examinations for further diagnosis, including carbohydrate antigen 199 (CA199), carcinoembryonic antigen (CEA), carbohydrate antigen 125 (CA125), contrast-enhanced CT (CECT) and CT angiography (CTA). His CA199, CEA, and CA125 marker levels were normal, which supported the diagnosis of a benign tumor. CECT showed a well-defined cystic-solid mass in the head of the pancreas, with a slightly enhanced solid portion and pancreatic ductal dilatation, which led us to consider the possibility of a malignant tumor. CTA revealed that the tumor nourishing arteries emitted from the pancreaticoduodenal superior and inferior arteries into the mass. Then, the patient underwent a pancreaticoduodenectomy. Finally, postoperative pathology and immunohistochemistry confirmed UC-OGC of the pancreas. INTERVENTIONS: The patient has been treated by a pancreaticoduodenectomy alone. OUTCOMES: The operation had no complications, and the patient recovered well after surgery. Ten months after surgery, the patient reviewed the CECT, and no recurrence or metastasis was noted. LESSONS: Old patients with cystic-solid lesions in the pancreas should be aware of UC-OGC. CT findings usually show a clear boundary and a slightly enhanced mass with pancreatic duct expansion.