Differentiation of Sporadic Versus Tuberous Sclerosis Complex-Associated Angiomyolipoma

Clinical practice recommendations for kidney involvement in tuberous sclerosis complex: a consensus statement by the ERKNet Working Group for Autosomal Dominant Structural Kidney Disorders and the ERA Genes & Kidney Working Group

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the presence of proliferative lesions throughout the body. Management of TSC is challenging because patients have a multifaceted systemic illness with prominent neurological and developmental impact as well as potentially severe kidney, heart and lung phenotypes; however, every organ system can be involved. Adequate care for patients with TSC requires a coordinated effort involving a multidisciplinary team of clinicians and support staff. This clinical practice recommendation was developed by nephrologists, urologists, paediatric radiologists, interventional radiologists, geneticists, pathologists, and patient and family group representatives, with a focus on TSC-associated kidney manifestations. Careful monitoring of kidney function and assessment of kidney structural lesions by imaging enable early interventions that can preserve kidney function through targeted approaches. Here, we summarize the current evidence and present recommendations for the multidisciplinary management of kidney involvement in TSC.

The effect of pregnancy on renal angiomyolipoma; a world of knowledge to gain, specifically in women with TSC

BACKGROUND

Women are counseled preconceptionally about the potential risks of rAML progression and chance of complications during and due to pregnancy. However, a systematic search investigating the evidence on which this advice is based does not exist. The aim of this systematic review is to determine the effect of pregnancy on renal angiomyolipoma (rAML) size and risk of haemorrhage in patients with tuberous sclerosis complex (TSC).

METHODS

We searched PubMed, EMBASE, Medline and ClinicalTrials.gov using terms for "renal angiomyolipoma" and "pregnancy". English-language articles published between January 1st 2000, and December 31st 2020 of which full-text was available were included. The initial search resulted in 176 articles. After the screening process we included 45 case reports and 1 retrospective study. For the retrospective study we assessed the risk of bias using the Newcastle-Ottawa Scale. We included articles about renal AML and pregnancy with and without an established diagnosis of TSC. From these articles we recorded the rAML sizes and rAML complications.

RESULTS

Seven case reports, from a total of 45 case reports, provided follow-up data on renal AML size (these were all cases of renal AML without a known diagnosis of TSC). Of these cases, renal AML size decreased in one patient, was stable in one patient, increased in three patients and fluctuated in two others. Renal AML size of women who suffered a haemorrhage were significantly larger (12.1 ± 4.6 cm) than rAMLs of women who did not suffer a haemorrhage (8.3 ± 3.2 cm). Data from the retrospective study showed no difference in renal complications between the women with and without a history of pregnancy. Haemorrhage occurred in 30% of the women with a history of pregnancy (n = 20) and in 11% in the patients without a history of pregnancy (n = 2), however this retrospective study had methodological limitations.

CONCLUSION

The effect of pregnancy on renal AML size and complications in patients with TSC is unclear. More research is needed to determine the risk of pregnancy on TSC-associated kidney disease in TSC patient.

Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma by the Japanese Urological Association: Summary of the update

New clinical issues have been raised through an interval of 7 years from the previous version (2016). In this study, we update the "Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma" as a 2023 version under guidance by the Japanese Urological Association. The present guidelines were cooperatively prepared by the Japanese Urological Association and Japanese Society of Tuberous Sclerosis Complex; committee members belonging to one of the two societies or specializing in the treatment of this disease were selected to prepare the guidelines in accordance with the "Guidance for preparing treatment guidelines" published by Minds (2020 version). The "Introduction" consisted of four sections, "Background Questions (BQ)" consisted of four sections, "Clinical Questions (CQ)" consisted of three sections, and "Future Questions (FQ)" consisted of three sections (total: 14 sections). Concerning CQ, an agreement was confirmed through voting by the committee members based on the direction and strength of recommendation, accuracy of evidence, and recommendation comments. The present guidelines were updated based on the current evidence. We hope that the guidelines will provide guiding principles for the treatment of tuberous sclerosis complex-associated renal angiomyolipoma to many urologists, becoming a foundation for subsequent updating.

Comparisons of the Safety and Effectiveness of Robot-Assisted vs Laparoscopic Partial Nephrectomy for Central Renal Angiomyolipomas: A Propensity Score-Matched Analysis Study

Objective: To compare the safety and effectiveness of robot-assisted partial nephrectomy (RAPN) vs laparoscopic partial nephrectomy (LPN) in the treatment of central renal angiomyolipomas (AMLs). Methods: We retrospectively analyzed the clinical data of 103 patients who were treated with either RAPN or LPN for central AMLs between January 2017 and June 2022. Propensity scores were matched according to sex, age, laterality, body mass index, symptoms, diameter of tumor, location of tumor distribution, R.E.N.A.L score, preoperative hemoglobin, preoperative serum creatinine, preoperative estimated glomerular filtration rate, chronic disease, previous abdominal surgery, preoperative selective arterial embolization, American Society of Anesthesiologists scale, and duration of follow-up, and after matching, perioperative and prognostic data of the two groups were compared. Results: A total of 57 patients underwent RAPN, and 46 patients underwent LPN. Before matching, there were more complex AMLs in the RAPN group, and R.E.N.A.L scores differed between the two groups (10 vs 9, p < 0.001). After matching, the median warm ischemic time in the RAPN group was significantly shorter than that in the LPN group (21.5 minutes vs 28 minutes, p = 0.034), as well as the median time of postoperative mobilization (1 day vs 2 days, p < 0.001). The other indicators were not significantly different between the groups. Conclusions: For central AMLs, both RAPN and LPN were safe and feasible surgical treatments, but RAPN might be associated with shorter warm ischemia time and earlier postoperative mobilization.

Missed tuberous sclerosis complex with multi-system complications in a single patient

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by widespread clinical manifestations. Early diagnosis is usually possible when typical TSC related skin lesions and neurologic presentations are detected in young patients. Undiagnosed TSC patients are at increased risk of morbidity and mortality as disease progression will inevitably lead to complications. While case reports of single complications in pediatric patients have been documented, to the best of our knowledge, multi-system complications of TSC in adults have yet to be reported in the literature. We present a case of tuberous sclerosis diagnosed in adulthood with complications involving the central nervous, renal and respiratory systems. This case highlights the need for a multidisciplinary approach in the management of TSC as well as the role of imaging in both diagnosis and intervention.

Utility of contrast-enhanced ultrasound for solid mass surveillance and characterization in children with tuberous sclerosis complex: an initial experience

BACKGROUND

Patients with tuberous sclerosis complex (TSC) can develop solid kidney masses from childhood. Imaging surveillance is done to detect renal cell carcinoma (RCC) and angiomyolipomas (AML), including AMLs at risk for hemorrhage. Intravenous contrast-enhanced ultrasound (CEUS) may be useful for screening as ultrasound is well tolerated by children and ultrasound contrast agents (UCA) are not nephrotoxic.

METHODS

Retrospective review of kidney CEUS exams of pediatric TSC patients. Qualitative CEUS analysis by consensus of 3 radiologists assessed rate, intensity, and pattern of lesion enhancement. Quantitative CEUS analysis was performed using Vuebox®. Where available, abdominal MRI was analyzed qualitatively for the same features and quantitatively by in-house-developed software. Time-intensity curves were generated from both CEUS and MRI where possible. Appearance of lesions were compared between CEUS and MRI and histology where available.

RESULTS

Nine masses in 5 patients included one histologically proven RCC and 8 AMLs diagnosed by imaging. Quantitative CEUS of RCC showed malignant features including increased peak enhancement 162%, rapid wash-in rate 162%, and elevated washout rate 156% compared to normal kidney tissue; versus AML which was 68%, 105%, and 125%, respectively. All masses were hypoenhancing on MRI compared to normal kidney tissue; MR dynamic contrast study offered no distinction between RCC and AML. The only MRI feature differentiating RCC from AML was absence of fat.

CONCLUSION

Temporal resolution afforded by CEUS was useful to distinguish malignant from benign kidney masses. CEUS may prove useful for screening, characterizing, and follow-up of kidney lesions in pediatric TSC patients.

The Correlation Between Tuberous Sclerosis Complex Genotype and Renal Angiomyolipoma Phenotype

Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that occurs between 1 in 6,000 and 1 in 10,000 live births. Additionally, renal angiomyolipoma is the most common form of renal disease in patients affected by TSC. Although a genetic mutation analysis of TSC is not rare, the correlation between the TSC gene mutation and renal angiomyolipoma phenotype is poorly understood. This study aims to analyze the mutation sites in 261 types of selected TSC patients. The results reveal that: (1) female patients develop more renal angiomyolipoma than male patients [p = 0.008, OR = 2.474, 95%CI (1.258–4.864)]; (2). The missense mutation of TSC1 led to a higher risk of renal angiomyolipoma [p < 0.01, OR = 15, 95%CI (2.859–78.691)], and in contrast, showed a reduced risk in patients with frameshift mutation [p = 0.03, OR = 0.252, 95%CI (0.07–0.912)]; (3). Patients with TSC2 mutations in the transcription activation domain 1 coding genes, had increased renal angiomyolipoma [p = 0.019, OR = 3.519, 95%CI (1.226–10.101)]. Therefore, our genotype-phenotype correlation study might shed light on the early monitoring and evaluation of renal angiomyolipoma in TSC patients.

A scoring system based on clinical features for the prediction of sporadic renal angiomyolipoma rupture and hemorrhage

The purpose of this study is to analyze the risk factors of sporadic renal hamartoma and establish a risk scoring system, and to intervene in patients with high-risk sporadic renal hamartoma who are prone to rupture and bleeding as soon as possible.Retrospective univariate and multivariate logistic analyzes were conducted for clinical data of 332 sporadic renal hamartoma patients to screen out independent risk factors of tumor rupture. Score of each independent risk factor was calculated. (Calculation formula: the risk coefficient of each factor = the beta regression coefficient of each factor/the minimum value of the beta regression coefficient of all factors, the value of the smallest beta regression coefficient corresponding to all the factors was assigned 1 point. The score of each factor was equal to the risk coefficient of each variable was taken as an integer value by rounding.) The total score was equal to the sum of all factors. Then the area under the receiver operating characteristics (AUC) curve was compared between high risk factors and scoring system. Finally, the scoring system was evaluated by the area under the curve (AUC) and the Hosmer-Lemeshow method in an independent cohort of 130 patients.Factors such as symptoms at presentation, tumor size, tumor blood supply, and tumor growth pattern were significant predictors of sporadic renal angiomyolipoma rupture in both the univariate and multivariate analyses; these predictors were included in the scoring system to predict sporadic renal angiomyolipoma rupture. There were no significant differences in AUCs between high risk factors and scoring system (z = 0.6434, P = .583, AUC = 0.913, and 0.903 for high risk factors and scoring system, respectively). The sporadic renal angiomyolipoma patients who scored >6 points were prone to rupture. AUROC of the scoring system in the validation set was 0.854(95%CI:0.779, 0.928). Using the Hosmer-Lemeshow method, the value of X was 2.916, P = .893, suggesting the scoring system fitted well.A scoring system based on clinical features is simple and effective in predicting sporadic angiolipoma rupture and hemorrhage. When the score is higher than 6 points, the probability of hamartoma rupture and hemorrhage is significantly increased and early intervention is needed.

Sporadic Angiomyolipomas Growth Kinetics While on Everolimus: Results of a Phase II Trial

PURPOSE

Everolimus decreases tumor volume of renal angiomyolipomas in patients with tuberous sclerosis. No prospective data are available regarding the effect of everolimus on the growth kinetics in patients with sporadic angiomyolipomas. We sought to determine the safety and efficacy of everolimus in the volumetric reduction of sporadic angiomyolipomas.

MATERIALS AND METHODS

This multi-institutional, prospective, phase II trial, enrolled patients with 3 cm or larger sporadic angiomyolipomas who were candidates for surgical resection or percutaneous angioembolization. Patients received 10 mg everolimus daily for 4 planned 28-day cycles. Response was defined as a 25% or greater volumetric reduction of patient angiomyolipoma. Baseline, 4, 6 and 12-month volumetric analyses were performed using magnetic resonance imaging. Everolimus was discontinued in those with less than 25% volumetric reduction after 4 cycles. Those with 25% or greater volumetric reduction received 2 additional cycles. The primary outcomes were the efficacy of everolimus in the volumetric reduction of angiomyolipomas by 25% or more, and the safety and tolerability of everolimus.

RESULTS

Overall 20 patients were enrolled at 5 centers. Of these patients 11 (55%) completed 4 cycles and 7 (35%) completed 6 cycles. Efficacy was demonstrated, with 10 of 18 (55.6%) patients exhibiting a 25% or greater reduction in tumor volume at 4 months (median 58.5%) and 10 of 14 (71.4%) patients exhibiting a 25% or greater reduction in tumor volume at 6 months (median 58.2%). Four (20%) patients were withdrawn due to protocol defined toxicities and 8 (40%) self-withdrew from the study due to side effects.

CONCLUSIONS

Everolimus was effective in causing volumetric reduction of angiomyolipomas by 25% or greater in most patients but was associated with a high rate of treatment discontinuation.

Deceased Donor Renal Transplantation Combined with Bilateral Nephrectomy in a Patient with Tuberous Sclerosis and Renal Failure

Introduction

A 27-year-old female patient with known tuberous sclerosis complex (TSC), polycystic kidneys with multiple large bilateral angiomyolipomas, and failing renal functions with prehemodialysis values (urea: 19 mmol/L; creatinine: 317 μmol/L; CKD-EPI 0,27) was admitted to our department for pre-renal transplant evaluation. The patient was placed on the transplant waiting list as the living donor did not pass pretransplant workup and was subsequently contraindicated. Patient was placed on the “cadaverous kidney transplant waiting list”.

Method

Computed tomography angiography revealed symptomatic PSA in the right kidney angiomyolipoma (AML). The patient underwent urgent transarterial embolisation of the PSA's feeding vessel in the right kidney AML. Based on the “kidney transplant waiting list” order patient underwent a bilateral nephrectomy combined with transperitoneal renal allotransplantation of a cadaverous kidney graft through midline laparotomy, appendectomy, and cholecystectomy.

Results

Postoperative period was complicated by delayed graft function caused by acute tubular necrosis requiring postoperative hemodialysis. The patient was discharged on the 17th postoperative day with a good renal graft function. Patient's follow-up is currently 23 months with good graft function (urea: 9 mmol/L; creatinine: 100 μmol/L).

Conclusion

Renal transplantation combined with radical nephrectomy provides a definitive treatment for TSC renal manifestations.

Angiomyolipoma rebound tumor growth after discontinuation of everolimus in patients with tuberous sclerosis complex or sporadic lymphangioleiomyomatosis

Introduction

The EXIST-2 (NCT00790400) study demonstrated the superiority of everolimus over placebo for the treatment of renal angiomyolipomas associated with tuberous sclerosis complex (TSC) or sporadic lymphangioleiomyomatosis (LAM). This post hoc analysis of EXIST-2 study aimed to assess angiomyolipoma tumor behavior among patients who submitted to continued radiographic examination following discontinuation of everolimus in the noninterventional follow-up phase.

Methods

For patients who discontinued everolimus at the completion of extension phase for reasons other than angiomyolipoma progression, a single CT/MRI scan of the kidney was collected after 1 year of treatment discontinuation. Changes from baseline and from the time of everolimus discontinuation in the sum of volumes of target angiomyolipoma lesions were assessed in the non-interventional follow-up phase (data cutoff date, November 6, 2015).

Results

Of the 112 patients who received ≥1 dose of everolimus and discontinued treatment by the end of extension phase, 34 (30.4%) were eligible for participation in the non-interventional follow-up phase. Sixteen of 34 patients were evaluable for angiomyolipoma tumor behavior as they had at least one valid efficacy assessment (i.e. kidney CT/MRI scan) after everolimus discontinuation. During the non-interventional follow-up phase, compared with baseline, two patients (12.5%) experienced angiomyolipoma progression (angiomyolipoma-related bleeding [n = 1], increased kidney volume [n = 1]). Five patients out of 16 (31.3%) experienced angiomyolipoma progression when compared with the angiomyolipoma tumor assessment at everolimus discontinuation. The median (range) percentage change in angiomyolipoma tumor volume (cm³) from baseline was −70.56 (−88.30; −49.64) at time of everolimus discontinuation (n = 11), and −50.55 (−79.40; −23.16) at week 48 (n = 7) after discontinuation of everolimus. One patient death was reported due to angiomyolipoma hemorrhage.

Conclusions

Angiomyolipoma lesions displayed an increase in volume following discontinuation of everolimus in patients with renal angiomyolipoma or sporadic LAM associated with TSC, but there was no evidence of rapid regrowth.

Trial registration

ClinicalTrials.gov NCT00790400

Factors associated with the number and size of renal angiomyolipomas in sporadic angiomyolipoma (sAML): a study of adult patients with sAML managed in a Dutch tertiary referral center

PURPOSE

To describe the patient characteristics, treatments, disease monitoring, and kidney function of patients with sporadic angiomyolipoma (sAML), stratified by the number and size of renal angiomyolipomas (AMLs).

METHODS

Single-center retrospective analysis of patients with sAML treated from 1990 to 2015 in a dedicated clinic for inheritable tumor syndromes in a tertiary referral center from the Netherlands. Patients' first AML assessment at the clinic was defined as the index date. Patient characteristics were measured at the index date. Treatments, disease monitoring, and kidney function were measured post-index date.

RESULTS

The study sample included 53 patients followed for a total of 184.6 patient-years. At the index date, the largest AML was ≥ 3.5 cm for 26 patients and < 3.5 cm for 27 patients (including six patients with five or more AMLs of < 3.5 cm). As compared to patients with AMLs < 3.5 cm, patients with largest AML ≥ 3.5 cm had higher frequency of pre-index bleeding episodes (31 vs. 4%), pre-index hypertension (35 vs. 15%), post-index nephrectomy (19 vs. 4%), post-index embolization (8 vs. 0%), and post-index renal scans (1.14 vs. 0.74 scans/year). Kidney impairment was especially pronounced in young adults with AML ≥ 3.5 cm. On average, patients with sAML developed chronic kidney disease stage two earlier than the general Dutch population (age 42 vs. 55 years), but later than the patients with tuberous sclerosis complex (35 years).

CONCLUSIONS

Patients with sAML, especially those with larger AMLs, have high disease burden.

Everolimus long-term use in patients with tuberous sclerosis complex: Four-year update of the EXIST-2 study

OBJECTIVES

We examined the long-term effects of everolimus in patients with renal angiomyolipoma associated with tuberous sclerosis complex or sporadic lymphangioleiomyomatosis.

METHODS

Following favorable results from the double-blind core phase of EXIST-2 (NCT00790400), patients were allowed to receive open-label everolimus (extension phase). Patients initially randomly assigned to everolimus continued on the same dose; those who were receiving placebo crossed over to everolimus 10 mg/day. Dose modifications were based on tolerability. The primary end point was angiomyolipoma response rate, defined as a ≥50% reduction from baseline in the sum volume of target renal angiomyolipomas in the absence of new target angiomyolipomas, kidney volume increase of >20% from nadir, and angiomyolipoma-related bleeding grade ≥2. The key secondary end point was safety.

RESULTS

Of the 112 patients who received ≥1 dose of everolimus, 58% (95% CI, 48.3% to 67.3%) achieved angiomyolipoma response. Almost all patients (97%) experienced reduction in renal lesion volumes at some point during the study period. Median duration of everolimus exposure was 46.9 months. Sixteen (14.3%) patients experienced angiomyolipoma progression at some point in the study. No angiomyolipoma-related bleeding or nephrectomies were reported. One patient on everolimus underwent embolization for worsening right flank pain. Subependymal giant cell astrocytoma lesion response was achieved in 48% of patients and skin lesion response in 68% of patients. The most common adverse events suspected to be treatment-related were stomatitis (42%), hypercholesterolemia (30.4%), acne (25.9%), aphthous stomatitis and nasopharyngitis (each 21.4%). Ten (8.9%) patients withdrew because of an adverse event. Renal function remained stable, and the frequency of emergent adverse events generally decreased over time.

CONCLUSIONS

Everolimus treatment remained safe and effective over approximately 4 years. The overall risk/benefit assessment supports the use of everolimus as a viable treatment option for angiomyolipoma associated with tuberous sclerosis complex or sporadic lymphangioleiomyomatosis.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00790400.

Tuberous sclerosis complex-associated renal angiomyolipomas: A single center study of 17 consecutive cases

The aim of the present study was to investigate the treatment options for patients with tuberous sclerosis complex (TSC)-associated renal angiomyolipomas (AMLs). A total of 17 patients who were consecutively diagnosed with TSC-associated renal AMLs at the Department of Urology of Zhongshan Hospital between 1998 and 2012 were included in the study. The patient cohort included 7 males and 10 females with a mean age of 37.6 years (range, 18-62 years). A total of 12 patients were diagnosed with renal AML with TSC during physical examination (PE), while 5 patients were admitted to the Emergency Department of Zhongshan Hospital due to spontaneous rupture of renal AMLs. All renal lesions were examined by ultrasonography and abdominal computed tomography prior to treatment. The primary outcome measure was the kidney reservation rate (patients that had not received nephrectomies) in the rupture group and PE group. Both abdominal ultrasonography and CT revealed AMLs in all patients and the mean tumor size was 10.0±4.0 cm (range, 3.0-17.5 cm). Overall, 9 patients underwent surgery, which included unilateral nephrectomy in 4 patients and unilateral partial nephrectomy/tumor enucleation in 5 patients. The remaining 8 patients received medical treatment. All patients were followed-up for between 10 and 67 months. One patient succumbed as a result of multiple organ failure, which was caused by hypovolemic shock due to the spontaneous rupture of renal AML. The kidney reservation rate during surgery was 87.5% (7/8) in the PE group and 25% (1/4) in the spontaneous rupture group. The management of TSC-associated renal AMLs differs from that of solitary sporadic AMLs. Surgical therapy is recommended following careful risk-benefit analysis.