Yuki Bekki

Dr. Yuki Bekki

orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 February 2023 in Transplantation Direct
Verified
Journal Article
Open access
YBYuki Bekki
Yuki Bekki
KCKristopher P. Croome
Kristopher P. Croome
BMBryan Myers
Bryan Myers
KSKazunari Sasaki
Kazunari Sasaki
KTKoji Tomiyama
Koji Tomiyama
Background.: Normothermic regional perfusion (NRP) has gained widespread adoption in multiple European countries. The aim of this study was to examine the influence of thoracoabdominal-NRP (TA-NRP) on the utilization and outcomes of liver, kidney, and pancreas transplantation in the United States. Methods.: Using the US national registry data between 2020 and 2021, donation after circulatory death (DCD) donors were separated into 2 groups: DCD with TA-NRP and without TA-NRP. There were 5234 DCD donors; among them 34 donors were with TA-NRP. After 1:4 propensity score matching, the utilization rates were compared between DCD with and without TA-NRP. Results.: Although the utilization rates of kidney and pancreas were comparable (P = 0.71 and P = 0.06, 94.1% versus 95.6% and 8.8% versus 2.2%, respectively), that of liver in DCD with TA-NRP was significantly higher (P < 0.001; 70.6% versus 39.0%). Among 24 liver transplantations, 62 kidney transplantations, and 3 pancreas transplantations from DCD with TA-NRP, there were 2 liver grafts and 1 kidney graft that failed within 1 y after transplantation. Conclusions.: TA-NRP in the United States significantly increased the utilization rate of abdominal organs from DCD donors with comparable outcomes after transplantation. Increasing use of NRP may expand the donor pool without compromising transplant outcomes.

6 April 2022 in Transplantation
Verified
Journal Article
Closed access
YBYuki Bekki
Yuki Bekki
JCJames F. Crismale
James F. Crismale
BMBryan Myers
Bryan Myers
TSThomas D. Schiano
Thomas D. Schiano
SFSander Florman
Sander Florman
Background.: Liver transplantation (LT) from hepatitis C virus (HCV)−positive donors [antibody positive (Ab+) or nucleic acid test−positive (NAT+) donors] has been reported to achieve successful outcomes. However, donor and recipient selection has not been well-characterized. Methods.: Data between 2015 and 2019 were obtained from the United Network for Organ Sharing database. The utilization rates and graft survival among 35 239 potential donors and 23 780 adult LT recipients were reviewed based on donor HCV Ab/NAT status. Results.: The utilization of Ab+/NAT+ donors was significantly reduced compared with HCV-negative donors (66.4% versus 80.0%, P < 0.001) among donors aged between 40 and 69 y. Recipients of livers from HCV-positive donors had lower laboratory and allocation Model for End-stage Liver Disease scores (both P < 0.001). HCV-positive donors were younger (P < 0.001). Kaplan-Meyer survival curves demonstrated significantly superior 1-y graft survival in recipients of HCV-positive grafts compared with those from HCV-negative grafts (P = 0.004; 97.1% in Ab−/NAT+, 93.9% in Ab+/NAT−, and 93.7% in Ab+/NAT+ versus 91.8% in Ab−/NAT−). Multivariate analysis for 1-y graft survival identified donor age [hazard ratio (HR) = 1.01; 95% confidence interval (CI), 1.00-1.01] and laboratory Model for End-stage Liver Disease score (HR = 1.01; 95% CI, 1.00-1.01) as independent predictors but not donor HCV status: HR 0.77‚ 95% CI, 0.58-1.02 in Ab+/NAT−; HR 0.82‚ 95% CI, 0.66-1.03 in Ab+/NAT+; and HR 0.39‚ 95% CI, 0.10-1.55 in Ab−/NAT+. Conclusions.: More widespread utilization of HCV-positive donors, especially Ab+/NAT+ donors of age 40–69 y, may expand the donor pool without impairing short-term outcomes after LT.

3 August 2022 in Clinical Transplantation
Verified
Journal Article
Closed access
YBYuki Bekki
Yuki Bekki
AKAkio Kozato
Akio Kozato
JKJiro Kusakabe
Jiro Kusakabe
TTTetsuya Tajima
Tetsuya Tajima
MFMasato Fujiki
Masato Fujiki
KSKazunari Sasaki
Kazunari Sasaki

16 August 2023 in Transplantation
Verified
Journal Article
Closed access
YBYuki Bekki
Yuki Bekki
BMBryan Myers
Bryan Myers
KTKoji Tomiyama
Koji Tomiyama
YIYuki Imaoka
Yuki Imaoka
MAMiho Akabane
Miho Akabane
KSKazunari Sasaki
Kazunari Sasaki
Background.: The allocation system for livers began using acuity circles (AC) in 2020. In this study, we sought to evaluate the impact of AC policy on the utilization rate for liver transplantation (LT). Methods.: Using the US national registry data between 2018 and 2022, LTs were equally divided into 2 eras: pre-AC (before February 4, 2020) and post-AC (February 4, 2020, and after). Deceased potential liver donors were defined as deceased donors from whom at least 1 organ was procured. Results.: The annual number of deceased potential liver donors increased post-AC (from 10 423 to 12 259), approaching equal to that of new waitlist registrations for LT (n = 12 801). Although the discard risk index of liver grafts was comparable between the pre- and post-AC eras, liver utilization rates in donation after brain death (DBD) and donation after circulatory death (DCD) donors were lower post-AC (P < 0.01; 79.8% versus 83.4% and 23.7% versus 26.0%, respectively). Recipient factors, ie, no recipient located, recipient determined unsuitable, or time constraints, were more likely to be reasons for nonutilization after implementation of the AC allocation system compared to the pre-AC era (20.0% versus 12.3% for DBD donors and 50.1% versus 40.8% for DCD donors). Among non–high-volume centers, centers with lower utilization of marginal DBD donors or DCD donors were more likely to decrease LT volume post-AC. Conclusions.: Although the number of deceased potential liver donors has increased, overall liver utilization among deceased donors has decreased in the post-AC era. To maximize the donor pool for LT, future efforts should target specific reasons for liver nonutilization.

18 November 2025 in International Journal of Surgery
Verified
Journal Article
Open access
CJCristina Jiménez-Soto
Cristina Jiménez-Soto
MBMatthew M Byrne
Matthew M Byrne
ALAbigail Faith Loszko
Abigail Faith Loszko
Yutaka EndoYutaka Endo
Yutaka Endo
ANAmit Nair
Amit Nair
KTKoji Tomiyama
Koji Tomiyama
Background: Histotripsy is a novel, non-invasive, focused ultrasound therapy that mechanically disrupts targeted tissues through cavitation, offering a precise and non-thermal alternative to conventional locoregional therapies with preservation of vascular and biliary structures. There are limited reports on the early use of histotripsy in primary and secondary liver tumors. Materials and Methods: Patients undergoing histotripsy for the treatment of primary and secondary liver tumors were retrospectively analyzed. The response to histotripsy was evaluated by assessing computed tomography findings in the first 3 months post-procedure period. Results: Twenty-seven patients were included in the study. Nine (33%) received histotripsy with downstaging or bridging intent, whereas 18 (67%) received histotripsy as part of a palliative treatment approach. Among patients with downstaging or bridging intent, seven of eight (87.5%) evaluable patients showed no lesion growth ≤3 months post-procedure. In palliative patients, growth remained controlled during the first 3 months in three of nine (33%) cases, while increasing in the remaining six (67%). Interestingly, tumoral size decreased in tumors not targeted by histotripsy in four patients, including one palliative patient who was not responding to multiple prior treatments. After histotripsy, three patients were successfully downstaged for liver resection and five were eligible for liver transplantation. Conclusion: Histotripsy presents great potential for the treatment of liver tumors, achieving high rates of short-term local disease control while offering vascular and biliary protection advantages, unlike thermal methods. Further work is required to understand a possible response away from the target. Histotripsy, in combination with systemic therapies, could aid in bridging or downstaging patients with advanced disease to achieve surgical resection or transplantation.

10 June 2025 in Cancers
Verified
Journal Article
Open access
PDF file
ALAbigail Faith Loszko
Abigail Faith Loszko
MBMatthew M Byrne
Matthew M Byrne
CJCristina Jiménez-Soto
Cristina Jiménez-Soto
KTKoji Tomiyama
Koji Tomiyama
YBYuki Bekki
Yuki Bekki
RHRoberto Hernandez-Alejandro
Roberto Hernandez-Alejandro
Transplant oncology is a rapidly evolving discipline that incorporates oncology, transplant medicine, and surgery. As the field continues to grow, there remains an opportunity to enhance patient selection, detect recurrence after liver transplantation, and optimize treatment after recurrence. Liquid biopsies are an emerging resource to improve patient care. In this review, we evaluate the most recent available data on circulating tumor DNA and how it pertains to primary and metastatic hepatobiliary malignancies. We discuss the opportunities and current limitations to clinical practice, especially in relation to total hepatectomy and liver transplantation. We conclude that as both transplant oncology and our understanding of circulating tumor DNA continue to evolve, rigorous, prospective study is required to integrate this technology into a clinical paradigm.