Pancreatic serous cystadenocarcinoma diagnosed with liver metastasis at 7 years after the resection of the primary serous neoplastic lesion.

Pancreatic serous neoplasms are rare tumors that are usually benign. However, histopathological differentiation between benign (serous cystadenoma) and malignant (serous cystadenocarcinoma) lesions is difficult. We present the case of a patient with pancreatic serous cystadenocarcinoma that was diagnosed with liver metastasis 7 years after the resection of the primary serous neoplastic lesion. A woman in her 60 s was diagnosed with pancreatic serous cystadenoma based on imaging and histopathological examination findings. The tumor was resected, and the patient was followed up every 6 months to monitor tumor progression. At 7 years after the resection of the primary lesion, liver tumors showing marked flare-like contrast enhancements were detected on arterial phase computed tomography findings and on dynamic magnetic resonance imaging findings acquired 60 s after the administration of a contrast agent. Laparoscopic segmental hepatectomy of S4 and S6 was performed to resect these tumors. Histopathological examination revealed that these tumors were metastatic and developed from the primary lesion. Therefore, a diagnosis of serous cystadenocarcinoma was confirmed. The flare-like contrast enhancement around the metastatic liver lesions on computed tomography and dynamic magnetic resonance images may be an indicator of serous cystadenocarcinoma with liver metastasis that could assist in diagnosis.