Kidney Volume Growth and Kidney Function of en bloc Pediatric Kidney Transplants: A Case Series

Rationale & Objective

Kidney transplant is a mainstay of kidney replacement therapy. Given a continued shortage of organs, pediatric en bloc kidney transplants may have substantial utility. We present our long-term experience with en bloc transplants from donors aged 3 to 60 months, including changes in kidney function and kidney volume over time as well as biopsy findings.

Study Design

Case series.

Setting & Participants

Medical records from a single academic medical center were reviewed. Aggregate serial volumes of 22 en bloc kidney allografts from 2010 to 2017 were assessed at the time of transplant and during follow-up. Estimated glomerular filtration rates (eGFR) were described at 3 months after transplant (baseline) as well as over the ensuing 3 years. Interstitial fibrosis, a finding determined by histopathologic review, which results from an accumulation of collagen that is produced from mediators produced from complex interaction of multiple inflammatory cells, was assessed on 20 protocol biopsies obtained from 6 patients, of which 4 patients had 4 biopsies and 2 patients had 1 biopsy.

Results

Kidney volume was obtained from 51 ultrasound studies performed up to 74 months after transplant. Kidney volume generally increased and eGFR rose over time after the transplant, with 23% patients achieving an eGFR of >75 mL/min/1.73 m² at 3 months posttransplant. The remainder achieved an eGFR >75 mL/min/1.73 m² over the ensuing 3 years. Interstitial fibrosis noted on biopsies appeared to foreshadow an eventual reduction in kidney volume.

Limitations

Retrospective study, possible selection bias, single-center experience.

Conclusions

The kidney en bloc allografts increased in size after transplantation, with associated improved kidney function. Chronic damage to the graft, from interstitial fibrosis and tubular atrophy, resulted in long-term reduction in kidney volume.

Simultaneous robotic kidney transplantation and bariatric surgery for morbidly obese patients with end-stage renal failure

Patients with obesity have limited access to kidney transplantation, mainly due to an increased incidence of surgical complications, which could be reduced with selective use of robotic-assisted surgery. This prospective randomized controlled trial compares the safety and efficacy of combining robotic sleeve gastrectomy and robotic-assisted kidney transplant to robotic kidney transplant alone in candidates with class II or III obesity. Twenty candidates were recruited, 11 were randomized to the robotic sleeve gastrectomy and robotic-assisted kidney transplant group and 9 to the robotic kidney transplant group. At 12-month follow-up, change in body mass index was -8.76 ± 1.82 in the robotic sleeve gastrectomy and robotic-assisted kidney transplant group compared to 1.70 ± 2.30 in the robotic kidney transplant group (P = .0041). Estimated glomerular filtration rate, serum creatinine, readmission rates, and graft failure rates up to 12 months were not different between the two groups. Length of surgery was longer in the robotic sleeve gastrectomy and robotic-assisted kidney transplant group (405 minutes vs. 269 minutes, p = .00304) without increase in estimated blood loss (120 ml vs. 117 ml, p = .908) or incidence of surgical complications. Combined robotic-assisted kidney transplant and sleeve gastrectomy is safe and effective compared to robotic-assisted kidney transplant alone.

Combination Immunotherapy With LIGHT and Interleukin-2 Increases CD8 Central Memory T-Cells In Vivo

BACKGROUND

The generation of long-term durable tumor immunity and prolonged disease-free survival depends on the ability to generate and support CD8+ central memory T-cells. Microsatellite-stable colon cancer is resistant to currently available immunotherapies; thus, development of novel mechanisms to increase both lymphocyte infiltration and central memory formation are needed to improve outcomes in these patients. We have previously demonstrated that both interleukin-2 (IL-2) and LIGHT (TNFSF14) independently enhance antitumor immune responses and hypothesize that combination immunotherapy may increase the CD8+ central memory T-cell response.

METHODS

Murine colorectal cancer tumors were established in syngeneic mice. Tumors were treated with control, soluble, or liposomal IL-2 at established intervals. A subset of animal tumors overexpressed tumor necrosis superfamily factor LIGHT (TNFSF14). Peripheral blood, splenic, and tumor-infiltrating lymphocytes were isolated for phenotypic studies and flow cytometry.

RESULTS

Tumors exposed to a combination of LIGHT and IL-2 experienced a decrease in tumor size compared with IL-2 alone that was not demonstrated in wild-type tumors or between other treatment groups. Combination exposure also increased splenic central memory CD8+ cells compared with IL-2 administration alone, while not increasing tumor-infiltrating lymphocytes. In the periphery, the combination enhanced levels of circulating CD8 T-cells and central memory T-cells, while also increasing circulating T-regulatory cells.

CONCLUSIONS

Combination of IL-2, whether soluble or liposomal, with exposure to LIGHT results in increased CD8+ central memory cells in the spleen and periphery. New combination immunotherapy strategies that support both effector and memory T-cell functions are critical to enhancing durable antitumor responses and warrant further investigation.

Tracheostomy Following Liver Transplantation

BACKGROUND

With increased demand for liver transplantation, sicker patients are being transplanted frequently. These patients are at a higher risk of significant postoperative morbidity, including respiratory failure. This study evaluated the phenotype that characterizes liver transplant candidates who may benefit from early tracheostomy.

METHODS

A single center retrospective review of all liver transplant candidates between January 2012 and December 2017. Patients who eventually required tracheostomies were identified and compared to their counterparts.

RESULTS

Of the 130 liver transplants performed during the study period, 11 patients required tracheostomy. Although patients in the tracheostomized population (TP) did not have significantly worse preoperative functional status (<4 metabolic equivalents; 64% vs 42%, P = .21), they had a higher native model for end-stage liver disease (MELD) score (37 vs 30, P < .05) at the time of transplantation. Patients who eventually succumbed to respiratory failure had lower arterial pressure of oxygen/fraction of inspired oxygen (PaO₂/FiO₂) ratios at the start of surgery and remained unchanged for the duration of surgery compared with the nontracheostomy group (P < .05). TP patients required more net fluid intraoperatively (7.3 vs 5.0 L, P < .05), increased length of time to attempted extubation (3.5 vs 1 day, P < .05), longer ventilation days (15 vs 1 day, P < .05), increased length of stay (37 vs 9 days, P < .05), and higher 1-year mortality (36% vs 8%, P < .05).

CONCLUSIONS

Based on our findings, patients with a high MELD score (>30), net postoperative fluid balance >6 L, and PaO₂/FiO₂ ratio ≤300 who fail to wean off mechanical ventilation after 72 hours may benefit from tracheostomy during the postoperative period.

Simultaneous recipient external iliac endarterectomy and renal transplant - a propensity score matched analysis

Patients with end-stage renal disease and severe iliac atherosclerosis are frequently denied renal transplant due to technical challenges, and risk of potential steal syndrome in the allograft, or ipsilateral limb. Few studies have evaluated the safety and efficacy of performing an endarterectomy in this setting. A single-center retrospective review of renal transplant patients from 1/2013 to 12/2017 was performed. Patients requiring endarterectomy at the time of transplant were matched to a nonendarterectomized cohort in a 1:2 fashion using propensity score matching. Patients were followed for a minimum of 12 months. Simultaneous endarterectomy and renal transplant were performed in 23 patients and subsequently matched to 42 controls. Ankle-brachial index was lower in the endarterectomized group (P = 0.04). Delayed graft function (26.1% vs. 19%, P = 0.54), graft loss (8.7% vs. 7.1%, P = 0.53), 1-year mortality (8.7% vs. 4.8%, P = 0.53), and renal function at 12 months were comparable in both groups. There were no incidents of ipsilateral limb loss in the endarterectomized population. This is the first matched study investigating endarterectomy and renal transplant. Long-term follow-up of limb and graft function is indicated. Despite the small sample size, our findings suggest that a combined procedure can safely provide renal transplantation access to a previously underserved population.

MADD silencing enhances anti-tumor activity of TRAIL in anaplastic thyroid cancer

ATC is an aggressive disease with limited therapeutic options due to drug resistance. TRAIL is an attractive anti-cancer therapy that can trigger apoptosis in a cancer cell-selective manner. However, TRAIL resistance is a major clinical obstacle for its use as a therapeutic drug. Previously, we demonstrated that MADD is a cancer cell pro-survival factor that can modulate TRAIL resistance. However, its role, if any, in overcoming TRAIL resistance in ATC is unknown. First, we characterized ATC cell lines as either TRAIL resistant, TRAIL sensitive or moderately TRAIL sensitive and evaluated MADD expression/cellular localization. We determined the effect of MADD siRNA on cellular growth and investigated its effect on TRAIL treatment. We assessed the effect of combination treatment (MADD siRNA and TRAIL) on mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels. The effect of combination treatment on tumor growth was assessed in vivo. We found increased levels of MADD in ATC cells relative to Nthy-ori 3-1. MADD protein localizes in the cytosol (endoplasmic reticulum and Golgi body) and membrane. MADD knockdown resulted in spontaneous cell death that was synergistically enhanced when combined with TRAIL treatment in otherwise resistant ATC cells. Combination treatment resulted in a significant reduction in MMP and enhanced generation of ROS indicating the putative mechanism of action. In an orthotopic mouse model of TRAIL-resistant ATC, treatment with MADD siRNA alone reduced tumor growth that, when combined with TRAIL, resulted in significant tumor regressions. We demonstrated the potential clinical utility of MADD knockdown in sensitizing cells to TRAIL-induced apoptosis in ATC.

Therapeutic advances in anaplastic thyroid cancer: a current perspective

Thyroid cancer incidence is increasing at an alarming rate, almost tripling every decade. In 2017, it was the fifth most common cancer in women. Although the majority of thyroid tumors are curable, about 2-3% of thyroid cancers are refractory to standard treatments. These undifferentiated, highly aggressive and mostly chemo-resistant tumors are phenotypically-termed anaplastic thyroid cancer (ATC). ATCs are resistant to standard therapies and are extremely difficult to manage. In this review, we provide the information related to current and recently emerged first-line systemic therapy (Dabrafenib and Trametinib) along with promising therapeutics which are in clinical trials and may be incorporated into clinical practice in the future. Different categories of promising therapeutics such as Aurora kinase inhibitors, multi-kinase inhibitors, epigenetic modulators, gene therapy using oncolytic viruses, apoptosis-inducing agents, and immunotherapy are reviewed. Combination treatment options that showed synergistic and antagonistic effects are also discussed. We highlight ongoing clinical trials in ATC and discuss how personalized medicine is crucial to design the second line of treatment. Besides using conventional combination therapy, embracing a personalized approach based on advanced genomics and proteomics assessment will be crucial to developing a tailored treatment plan to improve the chances of clinical success.