A case of intraductal papillary neoplasm of the bile duct which could be followed up for 10 years

Abstract

A 76-year-old man was noted to have a liver cyst in the left lobe during a medical checkup 10 years ago. The cyst, which measured 32mm in 2012, had gradually increased to 54mm by 2020, along with an elevated serum CA19-9 level. In 2023, a nodule with contrast effect was detected within the cyst, and the patient was referred to our hospital. A computed tomography scan revealed a 22mm nodule within a 62mm cyst, and positron emission tomography-computed tomography showed high accumulation corresponding to the nodule. Laparoscopic left hepatectomy was performed based on the diagnosis of hepatic cystadenocarcinoma. On histopathological examination, low-grade epithelial tumor cells with papillary and tubular growth covered the inner surface of the cyst and presented a gastric pit-like structure. Non-invasive well-differentiated adenocarcinoma was also identified in the nodule. No mucus or ovarian-like stroma was found, and it was considered consistent with gastric-type IPNB. We believe this case is a valuable report of IPNB observed over a 10-year period.