Hemorrhagic cystic lesion of pancreatic head: A case of acinar cell carcinoma which was difficult to diagnose preoperatively

The patient visited our hospital for evaluation of pancreatic head tumor secondary to upper abdominal pain. The lesion was detected as cystic with hemorrhagic component and observed as pseudocyst. After a year, the size became bigger and sonazoid-enhanced endoscopic ultrasonography showed internal enhancement. The lesion was recognized as solid and neoplastic and the operation was performed. The histopathologic evaluation revealed the lesion as acinar cell cartinoma with intratumoral necrosis and hemorrhage.