Planned limited resection of the extrahepatic bile duct in a case of intraductal papillary neoplasm of the bile duct based on preoperative examinations.

Intraductal papillary neoplasm of the bile duct (IPNB) is defined as a non-invasive malignancy; however, since there are disparities in its histological diagnosis, the operative strategy for typical IPNB has not yet been established. A 69-year-old male was diagnosed with a bile duct mass lesion at the confluence of the cystic duct by ultrasonography without clinical symptoms. Liver functional parameters and tumor markers were within normal ranges. Computed tomography showed an enhanced tumor with no findings of ductal invasion or node metastasis. The tumor was exposed in the hepatic duct lumen and biopsy via SpyGlass DS cholangiography revealed that it was a low-grade papillary lesion, indicating type 1 IPNB. Under preoperative diagnostic modalities, limited resection of the extrahepatic bile duct with D2 lymphadenectomy was planned and R0 resection was achieved. The postoperative histological diagnosis was type 1 IPNB without node metastasis. The postoperative course was uneventful and a good prognosis is expected at this stage. In the field of biliary surgery, although extended resection is generally performed for bile duct carcinomas, satisfactory limited surgical resection is possible for type 1 IPNB with lower malignant behavior.