John P. Roberts

Prof. Dr. John P. Roberts


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

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

Representative Publications

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23 September 2013 in Liver Transplantation
Verified
Journal Article
Open access
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NMNeil Mehta MD
Neil Mehta MD
JDJennifer L. Dodge
Jennifer L. Dodge
AGAparna Goel
Aparna Goel
JRJohn P. Roberts
John P. Roberts
RHRyutaro Hirose
Ryutaro Hirose
FYFrancis Y. Yao
Francis Y. Yao
It has been shown that patients with hepatocellular carcinoma (HCC) meeting the United Network for Organ Sharing T2 (Milan) criteria have an advantage in comparison with patients without HCC under the current organ allocation system for liver transplantation (LT). We hypothesized that within the T2 HCC group, there is a subgroup with a low risk of wait-list dropout that should not receive the same listing priority. This study evaluated 398 consecutive patients with T2 HCC listed for LT with a Model for End-Stage Liver Disease exception from March 2005 to January 2011 at our center. Competing risk (CR) regression was used to determine predictors of dropout. The probabilities of dropout due to tumor progression or death without LT according to the CR analysis were 9.4% at 6 months and 19.6% at 12 months. The median time from listing to LT was 8.8 months, and the median time from listing to dropout or death without LT was 7.2 months. Significant predictors of dropout or death without LT according to a multivariate CR regression included 1 tumor of 3.1 to 5 cm (versus 1 tumor of 3 cm or less), 2 or 3 tumors, a lack of a complete response to the first locoregional therapy (LRT), and a high alpha-fetoprotein (AFP) level after the first LRT. A subgroup (19.9%) that met certain criteria (1 tumor of 2 to 3 cm, a complete response after the first LRT, and an AFP level ≤ 20 ng/mL after the first LRT) had 1- and 2-year probabilities of dropout of 1.3% and 1.6%, respectively, whereas the probabilities were 21.6% and 26.5% for all other patients (P = 0.004). In conclusion, a combination of tumor characteristics and a complete response to the first LRT define a subgroup of patients with a very low risk of wait-list dropout who do not require the same listing priority. Our results may have important implications for the organ allocation policy for HCC. Liver Transpl 19:1343-1353, 2013. © 2013 AASLD.

2 February 2016 in American Journal of Transplantation
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Journal Article
Open access
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MMMarc Melcher
Marc Melcher
JRJohn P. Roberts
John P. Roberts
ALA. B. Leichtman
A. B. Leichtman
ARA. E. Roth
A. E. Roth
MRM. A. Rees
M. A. Rees
We propose that some deceased donor (DD) kidneys be allocated to initiate nonsimultaneous extended altruistic donor chains of living donor (LD) kidney transplants to address, in part, the huge disparity between patients on the DD kidney waitlist and available donors. The use of DD kidneys for this purpose would benefit waitlisted candidates in that most patients enrolled in kidney paired donation (KPD) systems are also waitlisted for a DD kidney transplant, and receiving a kidney through the mechanism of KPD will decrease pressure on the DD pool. In addition, a LD kidney usually provides survival potential equal or superior to that of DD kidneys. If KPD chains that are initiated by a DD can end in a donation of an LD kidney to a candidate on the DD waitlist, the quality of the kidney allocated to a waitlisted patient is likely to be improved. We hypothesize that a pilot program would show a positive impact on patients of all ethnicities and blood types.

1 October 2016 in Transplantation Reviews
Verified
Journal Article
Closed access
HBHillary J. Braun
Hillary J. Braun
NANancy L. Ascher
Nancy L. Ascher
GRGarrett R. Roll
Garrett R. Roll
JRJohn P. Roberts
John P. Roberts

1 June 2016 in Transplantation
Verified
Journal Article
Closed access
HBHillary J. Ba Braun
Hillary J. Ba Braun
JDJennifer Dodge
Jennifer Dodge
GRGarrett R. Roll
Garrett R. Roll
CFChris E. Freise
Chris E. Freise
NANancy L. Ascher
Nancy L. Ascher
JRJohn P. Roberts
John P. Roberts
Background Balancing donor and recipient risks in living donor liver transplantation remains an issue of debate. This study assessed the impact of graft selection on outcomes and complications for left lobe (LL) versus right lobe (RL) donors and recipients. Methods The medical records of donors and recipients, who underwent living donor liver transplantation at our institution between 2003 and 2015, were reviewed. For donors, we evaluated graft volume, residual liver volume per standard liver volume, length of hospital stay (LOS), complications, and readmissions. For recipients, we looked at graft and patient survival, graft function at postoperative days 7 and 14, graft volume, LOS, biliary complications, Model for End-Stage Liver Disease at transplant, and hepatitis C virus status. Results At 5 years posttransplant, there were no significant differences in graft survival for LL recipients (86% [95% confidence interval, 74-93]) compared with 82% (95% confidence interval, 69-89) for RL recipients (P = 0.85) or recipient survival (90% vs 84%; P = 0.44). In LL recipients, postoperative days 7 and 14 median international normalized ratio (1.5 and 1.2, respectively) and total bilirubin (4.6 and 2.7) were significantly greater compared with RL recipients (7 and 14 days international normalized ratio [1.2, P < 0.001; 1.1, P = 0.001] and total bilirubin (2.7, P = 0.001; 2.1, P = 0.05)). The LL recipients also had a significantly greater median LOS (14 vs 10, P = 0.008). Median donor LOS was significantly greater for RL donors (7 [interquartile range, 7-8] vs 7 [interquartile range, 6-7] days, P < 0.001). Conclusions The RL and LL grafts provide comparable long-term outcomes in properly selected donor-recipient pairs and the appropriate use of LL grafts does not impact graft or patient survival at 5 years posttransplant.

8 December 2020 in American Journal of Transplantation
Verified
Journal Article
Open access
HBHillary J. Braun
Hillary J. Braun
ATAna M. Torres
Ana M. Torres
FLFinesse Louie
Finesse Louie
SWSandra D. Weinberg
Sandra D. Weinberg
SKSang-Mo Kang
Sang-Mo Kang
JRJohn P. Roberts
John P. Roberts
Living donor liver transplantation (LDLT) enjoys widespread use in Asia, but remains limited to a handful of centers in North America and comprises only 5% of liver transplants performed in the United States. In contrast, living donor kidney transplantation is used frequently in the United States, and has evolved to commonly include paired exchanges, particularly for ABO-incompatible pairs. Liver paired exchange (LPE) has been utilized in Asia, and was recently reported in Canada; here we report the first LPE performed in the United States, and the first LPE to be performed on consecutive days. The LPE performed at our institution was initiated by a nondirected donor who enabled the exchange for an ABO-incompatible pair, and the final recipient was selected from our deceased donor waitlist. The exchange was performed over the course of 2 consecutive days, and relied on the use and compliance of a bridge donor. Here, we show that LPE is feasible at centers with significant LDLT experience and affords an opportunity to expand LDLT in cases of ABO incompatibility or when nondirected donors arise. To our knowledge, this represents the first exchange of its kind in the United States.

1 November 2009 in American Journal of Transplantation
Verified
Journal Article
Open access
PDF file
ARA. I. Reed
A. I. Reed
RMR. M. Merion
R. M. Merion
JRJohn P. Roberts
John P. Roberts
GKG. B. Klintmalm
G. B. Klintmalm
MAM. M. Abecassis
M. M. Abecassis
ALA. N. Langnas
A. N. Langnas
The American Society of Transplant Surgeons (ASTS) was asked to endorse the 'The Declaration of Istanbul on Organ Trafficking and Transplant Tourism.' The document has been reviewed by the ASTS Ethics Committee and their ensuing report was presented, discussed and approved by the ASTS Council. The ASTS vigorously supports the principles outlined in the Declaration and details specific current obstacles to implementation of some of its proposals in the United States.