Perihilar Cholangiocarcinoma – Novel Benchmark Values for Surgical and Oncological Outcomes From 24 Expert Centers
Authors: Mueller Matteo , Breuer Eva , Mizuno Takashi , Bartsch Fabian , Ratti Francesca , Benzing Christian , Ammar-Khodja Noémie , Sugiura Teiichi , Takayashiki Tsukasa , Hessheimer Amelia , Kim Hyung Sun , Ruzzenente Andrea , Ahn Keun Soo , Wong Tiffany , Bednarsch Jan , D'Silva Mizelle , Koerkamp Bas Groot , Jeddou Heithem , López-López Victor , de Ponthaud Charles , Yonkus Jennifer A. , Ismail Warsan , Nooijen Lynn E. , Hidalgo-Salinas Camila , Kontis Elissaios , Wagner Kim C. , Gunasekaran Ganesh , Higuchi Ryota , Gleisner Ana , Shwaartz Chaya , Sapisochin Gonzalo , Schulick Richard D. , Yamamoto Masakazu , Noji Takehiro , Hirano Satoshi , Schwartz Myron , Oldhafer Karl J. , Prachalias Andreas , Fusai Giuseppe K. , Erdmann Joris I. , Line Pål-Dag , Smoot Rory L. , Soubrane Olivier , Robles-Campos Ricardo , Boudjema Karim , Polak Wojciech G. , Han Ho-Seong , Neumann Ulf P. , Lo Chung-Mau , Kang Koo Jeong , Guglielmi Alfredo , Park Joon Seong , Fondevila Constantino , Ohtsuka Masayuki , Uesaka Katsuhiko , Adam René , Pratschke Johann , Aldrighetti Luca , De Oliveira Michelle L. , Gores Gregory J. , Lang Hauke , Nagino Masato , Clavien Pierre-Alain 
Published: August 2021

Objective:
The aim of this study was to define robust benchmark values for the surgical treatment of perihilar cholangiocarcinomas (PHC) to enable unbiased comparisons.

Background:
Despite ongoing efforts, postoperative mortality and morbidity remains high after complex liver surgery for PHC. Benchmark data of best achievable results in surgical PHC treatment are however still lacking.

Methods:
This study analyzed consecutive patients undergoing major liver surgery for PHC in 24 high-volume centers in 3 continents over the recent 5-year period (2014–2018) with a minimum follow-up of 1 year in each patient. Benchmark patients were those operated at high-volume centers (≥50 cases during the study period) without the need for vascular reconstruction due to tumor invasion, or the presence of significant co-morbidities such as severe obesity (body mass index ≥35), diabetes, or cardiovascular diseases. Benchmark cutoff values were derived from the 75th or 25th percentile of the median values of all benchmark centers.

Results:
Seven hundred eight (39%) of a total of 1829 consecutive patients qualified as benchmark cases. Benchmark cut-offs included: R0 resection ≥57%, postoperative liver failure (International Study Group of Liver Surgery): ≤35%; in-hospital and 3-month mortality rates ≤8% and ≤13%, respectively; 3-month grade 3 complications and the CCI: ≤70% and ≤30.5, respectively; bile leak-rate: ≤47% and 5-year overall survival of ≥39.7%. Centers operating mostly on complex cases disclosed better outcome including lower post-operative liver failure rates (4% vs 13%; P = 0.002). Centers from Asia disclosed better outcomes.

Conclusion:
Surgery for PHC remains associated with high morbidity and mortality with now the availability of benchmark values covering 21 outcome parameters, which may serve as key references for comparison in any future analyses of individuals, group of patients or centers.