Intraductal papillary neoplasms of the bile ducts: a comparative study of a rare disease in Europe and Nagoya, Japan

Background: Intraductal papillary neoplasm of the bile ducts (IPNB) is a rare disease in Western countries. The aim of this study was to compare tumor characteristics, management strategies, and outcomes between Western and Eastern patients who underwent surgical resection for IPNB. Methods: A multi -institutional retrospective series of patients with IPNB undergoing surgery between January 2010 and December 2020 was gathered under the auspices of the European -African HepatoPancreato-Biliary Association (E-AHPBA), and at Nagoya University Hospital, Japan. Results: A total of 85 patients (51% male; median age 66 years) from 28 E-AHPBA centers were compared to 91 patients (64% male; median age 71 years) from Nagoya. Patients in Europe had more multiple lesions (23% vs 2%, P < .001), less invasive carcinoma (42% vs 85%, P < .001), and more intrahepatic tumors (52% vs 24%, P < .001) than in Nagoya. Patients in Europe experienced less 90 -day grade >3 Clavien-Dindo complications (33% vs 68%, P < .001), but higher 90 -day mortality rate (7.0% vs 0%, P = .03). R0 resections (81% vs 82%) were similar. Overall survival, excluding 90 -day postoperative deaths, was similar in both regions. Discussion: Despite performing more extensive resections, the low perioperative mortality rate observed in Nagoya was probably influenced by a combination of patient-, tumor-, and surgery -related factors.