Obesity, organ failure, and transplantation: a review of the role of metabolic and bariatric surgery in transplant candidates and recipients.

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

Obesity, organ failure, and transplantation: A review of the role of metabolic and bariatric surgery in transplant candidates and recipients.

Obesity is a risk factor for kidney, liver, heart, and pulmonary diseases, as well as failure. Solid organ transplantation remains the definitive treatment for the end-stage presentation of these diseases. Among many criteria for organ transplant, efficient management of obesity is required for patients to acquire transplant eligibility. End-stage organ failure and obesity are 2 complex pathologies that are often entwined. Metabolic and bariatric surgery before, during, or after organ transplant has been studied to determine the long-term effect of bariatric surgery on transplant outcomes. In this review, a multidisciplinary group of surgeons from the Society of American Gastrointestinal and Endoscopic Surgeons and the American Society for Transplant Surgery presents the current published literature on metabolic and bariatric surgery as a therapeutic option for patients with obesity awaiting solid organ transplantation. This manuscript details the most recent recommendations, pharmacologic considerations, and psychological considerations for this specific cohort of patients. Since level one evidence is not available on many of the topics covered by this review, expert opinion was implemented in several instances. Additional high-quality research in this area will allow for better recommendations and, therefore, treatment strategies for these complex patients.

Histologic Findings of Sinusoidal Dilatation and Congestion in Liver Grafts Do Not Correlate with Hepatic Venous Anastomotic Gradients.

PURPOSE: Hepatic venous transplant anastomotic pressure gradient measurement and transjugular liver biopsy are commonly used in clinical decision-making in patients with suspected anastomotic hepatic venous outflow obstruction. This investigation aimed to determine if sinusoidal dilatation and congestion on histology are predictive of hepatic venous anastomotic outflow obstruction, and if it can help select patients for hepatic vein anastomosis stenting. MATERIALS AND METHODS: This is a single-center retrospective study of 166 transjugular liver biopsies in 139 patients obtained concurrently with transplant venous anastomotic pressure gradient measurement. Demographic characteristics, laboratory parameters, procedure and clinical data, and histology of time-zero allograft biopsies were analyzed. RESULTS: No relationship was found between transplant venous anastomotic pressure gradient and sinusoidal dilatation and congestion (P = 0.92). Logistic regression analysis for sinusoidal dilatation and congestion confirmed a significant relationship with reperfusion/preservation injury and/or necrosis of the allograft at time-zero biopsy (OR 6.6 [1.3-33.1], P = 0.02). CONCLUSION: There is no relationship between histologic sinusoidal dilatation and congestion and liver transplant hepatic vein anastomotic gradient. In this study group, sinusoidal dilatation and congestion is a nonspecific histopathologic finding that is not a reliable criterion to select patients for venous anastomosis stenting.

US Liver Transplant Outcomes After Normothermic Regional Perfusion vs Standard Super Rapid Recovery.

Importance: Normothermic regional perfusion (NRP) is an emerging recovery modality for transplantable allografts from controlled donation after circulatory death (cDCD) donors. In the US, only 11.4% of liver recipients who are transplanted from a deceased donor receive a cDCD liver. NRP has the potential to safely expand the US donor pool with improved transplant outcomes as compared with standard super rapid recovery (SRR). Objective: To assess outcomes of US liver transplants using controlled donation after circulatory death livers recovered with normothermic regional perfusion vs standard super rapid recovery. Design, Setting, and Participants: This was a retrospective, observational cohort study comparing liver transplant outcomes from cDCD donors recovered by NRP vs SRR. Outcomes of cDCD liver transplant from January 2017 to May 2023 were collated from 17 US transplant centers and included livers recovered by SRR and NRP (thoracoabdominal NRP [TA-NRP] and abdominal NRP [A-NRP]). Seven transplant centers used NRP, allowing for liver allografts to be transplanted at 17 centers; 10 centers imported livers recovered via NRP from other centers. Exposures: cDCD livers were recovered by either NRP or SRR. Main Outcomes and Measures: The primary outcome was ischemic cholangiopathy (IC). Secondary end points included primary nonfunction (PNF), early allograft dysfunction (EAD), biliary anastomotic strictures, posttransplant length of stay (LOS), and patient and graft survival. Results: A total of 242 cDCD livers were included in this study: 136 recovered by SRR and 106 recovered by NRP (TA-NRP, 79 and A-NRP, 27). Median (IQR) NRP and SRR donor age was 30.5 (22-44) years and 36 (27-49) years, respectively. Median (IQR) posttransplant LOS was significantly shorter in the NRP cohort (7 [5-11] days vs 10 [7-16] days; P < .001). PNF occurred only in the SRR allografts group (n = 2). EAD was more common in the SRR cohort (123 of 136 [56.1%] vs 77 of 106 [36.4%]; P = .007). Biliary anastomotic strictures were increased 2.8-fold in SRR recipients (7 of 105 [6.7%] vs 30 of 134 [22.4%]; P = .001). Only SRR recipients had IC (0 vs 12 of 133 [9.0%]; P = .002); IC-free survival by Kaplan-Meier was significantly improved in NRP recipients. Patient and graft survival were comparable between cohorts. Conclusion and Relevance: There was comparable patient and graft survival in liver transplant recipients of cDCD donors recovered by NRP vs SRR, with reduced rates of IC, biliary complications, and EAD in NRP recipients. The feasibility of A-NRP and TA-NRP implementation across multiple US transplant centers supports increasing adoption of NRP to improve organ use, access to transplant, and risk of wait-list mortality.

Hepatocellular carcinoma radiation segmentectomy treatment intensification prior to liver transplantation increases rates of complete pathologic necrosis: an explant analysis of 75 tumors.

PURPOSE: To verify the correlation between yttrium-90 glass microsphere radiation segmentectomy treatment intensification of hepatocellular carcinoma (HCC) and complete pathologic necrosis (CPN) at liver transplantation. METHODS: A retrospective, single center, analysis of patients with HCC who received radiation segmentectomy prior to liver transplantation from 2016 to 2021 was performed. The tumor treatment intensification cohort (n = 38) was prescribed radiation segmentectomy as per response recommendations identified in a previously published baseline cohort study (n = 37). Treatment intensification and baseline cohort treatment parameters were compared for rates of CPN. Both cohorts were then combined for an overall analysis of treatment parameter correlation with CPN. RESULTS: Sixty-three patients with a combined 75 tumors were analyzed. Specific activity, dose, and treatment activity were significantly higher in the treatment intensification cohort (all p < 0.01), while particles per cubic centimeter of treated liver were not. CPN was achieved in 76% (n = 29) of tumors in the treatment intensification cohort compared to 49% (n = 18) in the baseline cohort (p = 0.013). The combined cohort CPN rate was 63% (n = 47). ROC analysis showed that specific activity ≥ 327 Bq (AUC 0.75, p < 0.001), dose ≥ 446 Gy (AUC 0.69, p = 0.005), and treatment activity ≥ 2.55 Gbq (AUC 0.71, p = 0.002) were predictive of CPN. Multivariate logistic regression demonstrated that a specific activity ≥ 327 Bq was the sole independent predictor of CPN (p = 0.013). CONCLUSION: Radiation segmentectomy treatment intensification for patients with HCC prior to liver transplantation increases rates of CPN. While dose strongly correlated with pathologic response, specific activity was the most significant independent radiation segmentectomy treatment parameter associated with CPN.

Radiation Segmentectomy for the Treatment of Solitary Hepatocellular Carcinoma: Outcomes Compared with Those of Surgical Resection.

PURPOSE: To investigate the outcomes of radiation segmentectomy (RS) versus standard-of-care surgical resection (SR). MATERIALS AND METHODS: A multisite, retrospective analysis of treatment-naïve patients who underwent either RS or SR was performed. The inclusion criteria were solitary hepatocellular carcinoma ≤8 cm in size, Eastern Cooperative Oncology Cohort performance status of 0-1, and absence of macrovascular invasion or extrahepatic disease. Target tumor and overall progression, time to progression (TTP), and overall survival rates were assessed. Outcomes were censored for liver transplantation. RESULTS: A total of 123 patients were included (RS, 57; SR, 66). Tumor size, Child-Pugh class, albumin-bilirubin score, platelet count, and fibrosis stage were significantly different between cohorts (P ≤ .01). Major adverse events (AEs), defined as grade ≥3 per the Clavien-Dindo classification, occurred in 0 patients in the RS cohort vs 13 (20%) patients in the SR cohort (P < .001). Target tumor progression occurred in 3 (5%) patients who underwent RS and 5 (8%) patients who underwent SR. Overall progression occurred in 19 (33%) patients who underwent RS and 21 (32%) patients who underwent SR. The median overall TTP was 21.9 and 29.4 months after RS and SR, respectively (95% confidence interval [CI], 15.5-28.2 and 18.5-40.3, respectively; P = .03). Overall TTP subgroup analyses showed no difference between treatment cohorts with fibrosis stages 3-4 (P = .26) and a platelet count of <150 × 109/L (P = .29). The overall progression hazard ratio for RS versus SR was not significant per the multivariate Cox regression analysis (1.16; 95% CI, 0.51-2.63; P = .71). The median overall survival was not reached for either of the cohorts. Propensity scores were calculated but were too dissimilar for analysis. CONCLUSIONS: RS and SR were performed in different patient populations, which limits comparison. RS approached SR outcomes, with a lower incidence of major AEs, in patients who were not eligible for hepatectomy.

Variation in opioid prescribing patterns after abdominal transplant surgery.

BACKGROUND: Opioids are associated with negative transplant outcomes. We sought to identify patient and center effects on over-prescribing of opioids (> 200 OME (oral morphine equivalents)). STUDY DESIGN: Clinical and opioid prescription data (2014-2017) were collected from three academic transplant centers for kidney (KT), liver (LT), and simultaneous liver-kidney transplant (SLK) patients. Multivariable models were used to identify predictors of opioid over-prescribing at discharge and the occurrence of refill prescriptions at 90 days. RESULTS: Three-thousand seven-hundred and two patients underwent transplant in the cohort (KT: n = 2358, LT: n = 1221, SLK: n = 123). More than 80% of recipients were over-prescribed opioids at discharge (Median OME (mOME) = 300 (IQR 225-375). LT and SLK had the largest prescription size (LT mOME 338 (IQR 300-450); SLK mOME 338 (IQR 225-450) and refill rate (LT: 64%, SLK 59%) (all, P < .001). Multivariable analysis indicated that transplant center was a significant predictor of opioid over-prescription after KT and LT (all, P < .001); older age (in KT) and length of stay (LOS) (in LT) were protective factors (both, P < .05). Refill occurrence was associated with initial prescription size and was reduced by older age and initial LOS (all, P < .05). CONCLUSIONS: The wide variation in opioid prescribing patterns has implications for transplant practice innovation, guideline development, and further study.

Pathologic Response of Hepatocellular Carcinoma Treated with Yttrium-90 Glass Microsphere Radiation Segmentectomy Prior to Liver Transplantation: A Validation Study.

PURPOSE: To evaluate the pathologic outcomes of hepatocellular carcinoma (HCC) treated with Yttrium-90 radiation segmentectomy using glass microspheres prior to liver transplantation and explore parameters associated with pathologic necrosis. MATERIALS AND METHODS: A single-institution retrospective analysis of HCC patients who received radiation segmentectomy prior to liver transplantation from November 2016 to May 2020 was performed. Patients were included if the treatment angiosome encompassed the entire tumor and could be correlated with available gross pathology. Archived histology slides were reviewed for percentage of pathologic necrosis. Thirty-three patients with 37 tumors were evaluated. The median tumor size was 2.3 cm (range, 1-6.7 cm). RESULTS: All tumors received a single treatment. The median time from radiation segmentectomy to transplantation was 206 days (range, 58-550 days). Objective response per Modified Response Evaluation Criteria in Solid Tumors (mRECIST) was 92% (complete response, 76%; partial response, 16%). A total of 68% (n = 25) of tumors demonstrated ≥99% pathologic necrosis. Complete pathologic necrosis was present in 53% and 75% of tumors treated with >190 Gy (n = 18) and >500 Gy (n = 8) single-compartment Medical Internal Radiation Dose, respectively. Complete response per mRECIST, posttreatment angiosome T1 hypointensity, dose >190 Gy, microsphere specific activity >297 Bq, and a longer time between treatment and transplant were associated with ≥99% tumor necrosis (P < .05). No posttransplant tumor recurrences occurred within a median follow-up of 604 days (range, 138-1,223 days). CONCLUSIONS: Radiation segmentectomy can serve as an ablative modality for the treatment of HCC prior to liver transplant.

Sequential Protocol Biopsies Post-Liver Transplant From Donors With Moderate Macrosteatosis: What Happens to the Fat?

The number of steatotic deceased donor livers encountered has continued to rise as a result of the obesity epidemic. Little is known about the histological characteristics of moderately macrosteatotic livers over time in the recipient following liver transplantation (LT). All recipients undergoing LT at Mayo Clinic Florida with donor livers with moderate macrosteatosis (30%-60%) from 2000-2017 were identified (n = 96). Routine protocol liver biopsies were performed 1-week and 6-months following LT. All liver donor and protocol biopsies were read by an experienced liver pathologist. Of the 96 moderate macrosteatosis LTs, 70 recipients had post-LT protocol liver biopsies available and comprised the study cohort. Median donor allograft macrosteatosis at the time of transplant was 33% (IQR, 30%-40%) compared with 0% (IQR, 0%-2%) at 1-week (P < 0.001) and 0% (IQR, 0%-0%) at 6-months (P < 0.001) following LT. Biopsies at 1-week post-LT displayed pericentral necrosis in 57.1% of recipients and lipopeliosis in 34.3% of recipients. In the 6-month post-LT biopsies, cholestasis was seen in 3 (4.3%) of the recipients, whereas grade 2 fibrosis was seen in 6 recipients (8.6%). Graft survival at 5 years in the present cohort was 74.0%. Moderate macrosteatosis (30%-60%) in the donor allograft demonstrates complete reversal on liver biopsies performed as early as 7 days following LT and remains absent at 6-months following LT. Both pericentral necrosis and lipopeliosis are common features on day 7 biopsies. Despite these encouraging findings, the perioperative risks of using these livers (postreperfusion cardiac arrest and primary nonfunction) should not be understated. Long-term graft survival is acceptable in patients who are able to overcome the immediate perioperative risk of using moderately steatotic donor livers.

A 3-Decade Analysis of Pancreatic Adenocarcinoma After Solid Organ Transplant.

OBJECTIVE: Solid organ transplant (SOT) recipients have moderately increased risk of pancreatic adenocarcinoma (PAC). We evaluated the incidence and survival of PAC in 2 cohorts and aimed to identify potential risk factors. METHODS: This study performed a retrospective cohort analysis. Cohort A was extracted from the United Network of Organ Sharing data set and cohort B from SOT recipients evaluated at 3 Mayo Clinic transplant centers. The primary outcome was age-adjusted annual incidence of PAC. Descriptive statistics, hazard ratios, and survival rates were compared. RESULTS: Cohort A and cohort B included 617,042 and 29,472 SOT recipients, respectively. In cohort A, the annual incidence rate was 12.78 per 100,000 in kidney-pancreas, 13.34 in liver, and 21.87 in heart-lung transplant recipients. Receiving heart-lung transplant, 50 years or older, and history of cancer (in either recipient or donor) were independent factors associated with PAC. Fifty-two patients developed PAC in cohort B. Despite earlier diagnosis (21.15% with stage I-II), survival rates were similar to those reported for sporadic (non-SOT) patients. CONCLUSIONS: We report demographic and clinical risk factors for PAC after SOT, many of which were present before transplant and are common to sporadic pancreatic cancer. Despite the diagnosis at earlier stages, PAC in SOT portends a very poor survival.

Significance of proximal ductal margin status after resection of hilar cholangiocarcinoma.

BACKGROUND: The impact of additional resection for positive proximal bile duct margins during hepatic resection of hilar cholangiocarcinoma (HCCA) on survival and disease progression remains unclear. We asked how re-resection of positive proximal bile duct margins affected outcomes. METHODS: Patients undergoing resection between 1993-2017 were reviewed. Both frozen section and final margin status were reviewed. Overall survival was the primary outcome. RESULTS: 153 patients underwent surgical resection for HCCA. Median survival (months) for initial margin negative (M-), margin-positive to margin-negative (M+/M-) and margin-positive to margin-positive (M+/M+) was 45, 33, and 35 months respectively. Nodal metastases increased with margin positivity: 32% with M-, 49% with M+/M- and 63% with M+/M+ (p = 0.016). Local/regional progression more frequently occurred in M+/M- (27.3%) and M+/M+ (33.3%) patients (M+/M- vs. M-: p = 0.41, M+/M+ vs. M-: p = 0.27). Patients receiving postoperative chemotherapy were 33% M-, 46% M+/M- and 63% in M+/M+. Postoperative radiation was used in 13% of M-, 31% of M+/M- and 63% of M+/M+. Most frequent initial recurrences were within the liver and hepaticojejunostomy site. CONCLUSION: Competing risk for systemic disease based on primary characteristics of HCCA outweighs the impact of re-resection to achieve R0 status. Improved survival will likely depend on future regional and systemic therapy.

Simultaneous liver transplant and sleeve gastrectomy not associated with worse index admission outcomes compared to liver transplant alone - a retrospective cohort study.

Sleeve gastrectomy (SG) at the time of liver transplant (LT) has been argued to decrease resource utilization. However, larger studies examining outcomes are lacking. We aim to determine the outcomes of simultaneous SG and LT compared to LT alone. This is a retrospective cohort study using the 2011-2017 National Inpatient Sample (NIS). The primary outcome was the odds of inpatient mortality in patients undergoing simultaneous SG and LT compared with LT alone. Secondary outcomes included inpatient morbidity, resource utilization, hospital length of stay (LOS), and inflation-adjusted total hospital costs and charges. A total of 45 361 patients underwent LT in the study period, 49 underwent simultaneous SG. Patients undergoing simultaneous LT and SG had lower crude mortality (0.0%) compared to LT alone (2.97%; P = 0.52). There were no statistically significant differences in morbidity, resource utilization, and hospital costs and charges. Patients undergoing simultaneous LT and SG did not have significantly different mortality rates, morbidity, resource utilization, or LOS during the index admission when compared to LT alone. SG may be feasible at the time of LT in very carefully selected patients. Studies should focus in determining which patients are the optimal candidates to undergo simultaneous LT and SG.

Intraoperative Events in Liver Transplantation Using Donation After Circulatory Death Donors.

Liver grafts from donation after circulatory death (DCD) are a source of organs to decrease wait-list mortality. While there have been lower rates of graft loss, there are concerns of an increased incidence of intraoperative events in recipients of DCD grafts. We aim to look at the incidence of intraoperative events between recipients of livers from DCD and donation after brain death (DBD) donors. We collected data for 235 DCD liver recipients between 2006 and 2017. We performed a 1:1 propensity match between these patients and patients with DBD donors. Variables included recipient age, liver disease etiology, biological Model for End-Stage Liver Disease (MELD) score, allocation MELD score, diagnosis of hepatocellular carcinoma, and year of transplantation. DCD and DBD groups had no significant differences in incidence of postreperfusion syndrome (P = 0.75), arrhythmia requiring cardiopulmonary resuscitation (P = 0.66), and treatments for hyperkalemia (P = 0.84). In the DCD group, there was a significant increase in amount of total intraoperative and postreperfusion blood products (with exception of postreperfusion packed red blood cells) utilized (P < 0.05 for all products), significant differences in postreperfusion thromboelastography parameters, as well as inotropes and vasopressors used (P < 0.05 for all infusions). There was no difference in patient (P = 0.49) and graft survival (P = 0.10) at 1, 3, and 5 years. In conclusion, DCD grafts compared with a cohort of DBD grafts have a similar low incidence of major intraoperative events, but increased incidence of transient vasopressor/inotropic usage and increased blood transfusion requirements. This does not result in differences in longterm outcomes. While centers should continue to look at DCD liver donors, they should be cognizant regarding intraoperative care to prevent adverse outcomes.

Colorectal Cancer Characteristics and Outcomes after Solid Organ Transplantation.

BACKGROUND: Individuals after solid organ transplant may develop secondary malignancies. In our clinical practice, we noted an increasing number of individuals who developed colorectal cancers after solid organ transplantation. The primary aim of this study was to describe the characteristics and outcomes of the patients who developed colorectal cancer after solid organ transplant. MATERIALS AND METHODS: Data was gathered and merged from several registries at Mayo Clinic to identify all patients who received a diagnosis of colon or rectal cancer and solid organ transplant. Continuous variables were summarized as mean (standard deviation) and median (range), while categorical variables were reported as frequency (percentage). Time to colorectal cancer after transplant and overall survival after cancer diagnosis were estimated using Kaplan-Meier method. RESULTS: Initially, 115 colorectal cancer patients who also had a transplant were identified. The diagnosis of colorectal cancer was noted after solid organ transplant in 63 patients. The mean age at transplant was 57 years. Majority had received a kidney transplant (44.4%) followed by liver (36.5%). The median time to develop colorectal cancer was 59.3 months (range: 4.4-251.4 months). 15 (24.6%) were stage 4 at diagnosis and 13 (21.3%) had stage 3 colorectal cancer. Median overall survival was 30.8 months; 5-, 10- and 15-year survival were noted to be 42.5%, 17.9%, and 7.5%, respectively. None of the stage 4 patients were alive at 5 years; 5-year survival rate for stage 1, 2, and 3 patients was 77%, 50%, and 42%, respectively. CONCLUSIONS: Our study reports on one of the largest cohorts of patients of colorectal cancer that developed the cancer after solid organ transplant. Survival is extremely poor for advanced cases. However, long-term survivors are noted who developed the cancer at a relatively early stage. Colorectal screening recommendations may need to be revised for patients after solid organ transplant.