Cardiovascular manifestations of tuberous sclerosis complex and summary of the revised diagnostic criteria and surveillance and management recommendations from the International Tuberous Sclerosis Consensus Group

Clinical, genetic and quality-of-life study of a cohort of adult patients with tuberous sclerosis

Background and objective

Tuberous sclerosis (TS) is a condition whose manifestations in childhood have been extensively described, but whose presentation in adults is less well known. This study describes the clinical and genetic characteristics, therapeutic management and quality of life of a cohort of adult patients with TS. A comparative study of the characteristics of patients diagnosed in childhood and adulthood is also carried out.

Material and methods

This observational, retrospective, cross-sectional study included a large cohort of adult patients (≥ 16 years old) followed for 5 years in a specific rare diseases unit.

Results

Fifty-seven patients with a diagnosis of tuberous sclerosis were included, more than 50% of whom were diagnosed as adults. The mean age of the patients was 42 years (20–86). The central nervous system was the main area affected (97%), followed by the skin (80.7%) and kidneys (73%). The most frequent genetic alteration was a mutation in the TSC2 gene (47.7%). Among patients diagnosed in adulthood, there was less neurological involvement, with less frequency of epileptic seizures (30.8% vs 60.79% of patients diagnosed in childhood) and astrocytomas (3.8% vs 53.6%), less intellectual disability (11.5% vs 71.4%) and less expressiveness of the condition. 42% of patients were treated with mTOR pathway inhibitors, and presence of an angiomyolipoma was the main indication. In a quality-of-life analysis, the means of the summary indices were below the scores of the average Spanish population: (47.42 (SD ± 9.82) on the physical health scale, 45.61 (SD ± 7.99) on the mental health scale) versus 50 (SD ± 10) for the general population.

Conclusions

Up to 50% of adult patients with TS were diagnosed in adulthood, and the condition is less severe with less frequent epileptic seizures and intellectual disability. 42% require treatment with mTOR inhibitors, in most cases due to the presence of AMLs. The quality of life of adult patients with TS is diminished compared to the general population.

The outstanding role of miR-132-3p in carcinogenesis of solid tumors

MicroRNAs are a group of short non-coding RNAs (miRNAs), which are epigenetically involved in gene expression and other cellular biological processes and can be considered as potential biomarkers for cancer detection and support for treatment management. This review aims to amass the evidence to reach the molecular mechanism and clinical significance of miR-132 in different types of cancer. Dysregulation of miR-132 level in various types of malignancies, including hepatocellular carcinoma, breast cancer, colorectal cancer, gastric cancer, lung cancer, prostate cancer, osteosarcoma, pancreatic cancer, and ovarian cancer have reported, significantly decrease in its level, which can be indicated to its function as a tumor suppressor. miR-132 is involved in cell proliferation, migration, and invasion through cell cycle pathways, such as PI3K, TGFβ or hippo signaling pathways, or on oncogenes such as Ras, AKT, mTOR, glycolysis. miR-132 could be potentially a candidate as a valuable biomarker for prognosis in various cancers. Through this study, we proposed that miR-132 can potentially be a candidate as a prognostic marker for early detection of tumor development, progression, as well as metastasis.

Cardiac Rhabdomyoma in Adult

Cardiac rhabdomyoma is a hamartoma comprised of cardiac myocytes. It is the classic cardiac manifestation of tuberous sclerosis complex (TSC) which is an autosomal dominant genetic syndrome with multi-organ involvement, but highly variable phenotype. Cardiac rhabdomyoma is most commonly diagnosed in infancy, 70 to 90% of whom have TSC. However, TSC-associated cardiac rhabdomyoma usually shows spontaneous regression within the first two years of life and hence is extremely rare in adults. We present a 34-year-old woman with TSC who was found to have a cardiac rhabdomyoma when she was referred to the cardiology clinic for evaluation and to establish care. Cardiac rhabdomyoma is usually asymptomatic. However, depending on size and location, it can cause outflow or inflow tract obstruction and aberrant electrical conduction. Hence, appropriate surveillance is important.

Current concepts on ocular vascular abnormalities in the phakomatoses

BACKGROUND

Neurofibromatosis, Von Hippel Lindau disease, and tuberous sclerosis complex are classified under the term phakomatoses. They are characterized by ocular vascular abnormalities such as vascular tortuosity, corkscrew retinal vessel configuration, moyamoya-like aspect, microaneurysms, hemangioblastomas, and focal sheathing of retinal arteries, possibly due to abnormal formation, migration, and differentiation of neural crest cells. These alterations can be the first sign or the hallmark of disease and can be related to vasoproliferative tumors.

PURPOSE

Novel imaging technologies in ophthalmology, such as near-infrared reflectances and spectral domain optical coherence tomography, have improved our knowledge in the diagnosis of these pathologies. Previously undetected macular vascular alterations have been reported in phakomatoses using optical coherence tomography angiography. This review will summarize the ophthalmic vascular abnormalities and novel imaging methods in the phakomatoses.

CONCLUSION

Active research is being led into the ophthalmic management of these conditions and their complications, and owing to elevated vascular endothelial growth factor production from hemangioblastoma, hamartoma, and retinal vascular proliferative tumors, increasing interest in this line of therapy has been conducted although research is still ongoing in this area.

Efficacy of Everolimus Low-Dose Treatment for Cardiac Rhabdomyomas in Neonatal Tuberous Sclerosis: Case Report and Literature Review

Background: Cardiac rhabdomyomas (CRs) are the most common cardiac tumors in newborns. Approximately 80-90% of cases are associated with tuberous sclerosis complex (TSC). In selective cases, Everolimus has resulted in a remarkable tumoral regression effect in children with TS. The optimal dosage for neonates is still unknown. Case presentation: We describe the use of Everolimus in a neonate with multiple biventricular CRs, causing subaortic obstruction, in which a low-dose treatment (0.1 mg/die), in an effort to maintain serum trough levels of 3-7 ng/mL, was successfully used off-label, without adverse effects. Conclusions: We showed that a low-dose Everolimus regimen may be an effective and safe treatment for CR regression in TS neonates, when the minimum therapeutic range was maintained.

Combination percutaneous and medical management of cardiac rhabdomyomas obstructing tricuspid valve inflow: Case report

BACKGROUND

Cardiac rhabdomyomas can be prenatally diagnosed in patients with tuberous sclerosis complex. Many neonates require no intervention in early life other than close monitoring for regression of tumor over the period of months to years. In rare instances, cardiac rhabdomyomas can result in obstruction to blood flow or decreased ventricular function.

CASE REPORT

We describe the case of a neonate who was prenatally diagnosed with multiple large cardiac rhabdomyomas, one of which caused clinically significant obstruction to prograde blood flow across the tricuspid valve in the newborn period. To address the disturbance to prograde pulmonary blood flow, the patient underwent successful ductal stent placement in the neonatal period. A troponin elevation was noted shortly after birth, but no evidence of coronary compression or involvement was demonstrated by coronary angiography. The patient has subsequently been treated with sirolimus over a period of three months, with noted regression in tumors and improvement in tricuspid valve inflow.

CONCLUSIONS

A brief review of the literature regarding the diagnosis, treatment, and management of neonatal patients with cardiac rhabdomyomas is presented. A combined percutaneous and medical management approach may be of benefit in future cases of rhabdomyomas causing obstruction to pulmonary blood flow.

Performance of simultaneous multi-slice accelerated diffusion-weighted imaging for assessing focal renal lesions in pediatric patients with tuberous sclerosis complex

BACKGROUND

Diffusion-weighted imaging (DWI) is a useful MRI technique to characterize abdominal lesions in children, but long acquisition times can lead to image degradation. Simultaneous multi-slice accelerated DWI is a promising technique to shorten DWI scan times.

OBJECTIVE

To test the feasibility of simultaneous multi-slice DWI of the kidneys in pediatric patients with tuberous sclerosis complex (TSC) and to evaluate the accelerated protocol regarding image quality and quantitative apparent diffusion coefficient (ADC) values compared to standard echoplanar DWI sequence.

MATERIALS AND METHODS

We included 33 children and adolescents (12 female, 21 male; mean age 10±5 years) with TSC and renal cyst or angiomyolipoma on 3-tesla (T) MRI from 2017 to 2019. All studies included both free-breathing standard echoplanar DWI and simultaneous multi-slice DWI sequences. Subjective and quantitative image quality was evaluated using a predefined 5-point scale. ADC values were obtained for all renal cysts and angiomyolipomas ≥5 mm. All statistical analysis was performed using Stata/SE v15.1.

RESULTS

Simultaneous multi-slice DWI ADC values were slightly lower compared to standard echoplanar DWI for both renal cysts and angiomyolipomas (mean difference 0.05×10^-3 mm²/s, 95% confidence interval [CI] 0.40-0.50 and 0.024×10^-3 mm²/s, 95% CI 0.17-0.21, respectively, with P>0.1). Our results showed that renal lesions with ADC values >1.69×10^-3 mm²/s were all cysts, whereas lesions with values <1.16×10^-3 mm²/s were all angiomyolipomas. However, ADC values could not discriminate between lipid-rich and lipid-poor angiomyolipomas (P>0.1, for both sequences).

CONCLUSION

A 55% reduction in scan time was achieved using simultaneous multi-slice DWI for abdominal imaging in children with TSC, with near identical image quality as standard DWI. These results suggest that multi-slice techniques should be considered more broadly as an MRI acceleration technique in children.

Magnetic Resonance Imaging of Intramyocardial Fat Deposition in Tuberous Sclerosis

Tuberous sclerosis complex (TSC) is a rare autosomal dominant neurocutaneous syndrome. The phenotype is highly variable and may affect several organ systems, the hallmark of the disease being widespread hamartomas or abnormal growth of normal tissues. Although cardiac rhabdomyomas are the most common cardiac manifestation of TSC, being developed quite early, even during the second semester of the gestation, they tend to regress spontaneously over a period of months or years. On the other hand, the presence of intramyocardial fat deposition has been significantly associated with brain involvement and other extracardiac manifestations. We report the case of a 37-year-old man with TSC who presented to hospital with loss of consciousness, head injury and amnesia and in whom cardiac magnetic resonance imaging revealed the presence of multiple areas intramyocardial fat deposition.

Focal Status and Sub-Ependymal Tumor as Features of the First Presentation in a Child With Tuberous Sclerosis

Tuberous sclerosis (TS) is an autosomal dominant inherited disorder that affects multiple organ systems. Usually, children with TS present either with neurocutaneous stigmata or seizures during the early years of life. The mortality and morbidity are related to refractory epilepsy, giant cell astrocytoma and related complications, and multiple angiomyolipomas. The authors have reported an eleven-year-old child in whom focal status and sub-ependymal tumor were the features of the first presentation of tuberous sclerosis. The report further highlights the importance of early identification of cutaneous features by primary care providers and parents to enable early comprehensive multi-disciplinary management.

Tuberous sclerosis: a review of the past, present, and future

Tuberous sclerosis complex (TSC) is an autosomal dominant, multisystem disorder that is characterized by cellular and tissue dysplasia in several organs. With the advent of genetic and molecular techniques, mutations in the TSC1 or TSC2 genes were discovered to be responsible for mTOR overactivation, which is the underlying mechanism of pathogenesis. TSC is a highly heterogenous clinical entity with variable presentations and severity of disease. The brain, heart, skin, eyes, kidneys, and lungs are commonly involved in this syndrome, with neurologic symptoms comprising a significant source of morbidity and mortality. In 2012, the diagnostic criteria for TSC were revised by the International Tuberous Sclerosis Complex Consensus panel, and genetic testing was incorporated into the guidelines. Early detection of cardiac rhabdomyomas or TSC-associated skin lesions can suggest the diagnosis and underlie the importance of clinical vigilance. Animal studies have demonstrated the benefit of using mTOR inhibitors for various symptoms of TSC, and they have been successfully translated into clinical trials with significant improvement in symptom burden. Subependymal giant cell astrocytomas, renal angiomyolipomas, and epilepsy are the three FDA-approved indications in relation to TSC for the use of everolimus, which is a first generation mTOR inhibitor. Rapamycin has been FDA approved for lymphangioleiomyomatosis. Other TSC symptoms that could potentially benefit from this class of medication are currently under investigation. TSC constitutes a unique combination of protean physical symptoms and neurobehavioral abnormalities. TSC associated neuropsychiatric disorders (TAND), including intellectual disability, mood disorders, and autism spectrum disorder, represent significant challenges but remain underdiagnosed and undertreated. The TAND checklist is a useful tool for routine use in the clinical evaluation of TSC patients. A multidisciplinary treatment plan, based on the specific problems and needs of individuals, is the key to management of this genetic condition. Ongoing research studies have been providing promising leads for developing novel mechanistic strategies to address the pathophysiology of TSC.

Economic burden associated with tuberous sclerosis complex in patients with epilepsy

OBJECTIVES

Data on the economic burden associated with tuberous sclerosis complex (TSC) among patients with epilepsy in the United States (US) are limited. This study aimed to assess all-cause and epilepsy-related healthcare resource utilization (HRU) and healthcare costs in the US among patients with epilepsy and TSC compared with patients with epilepsy but without TSC.

METHODS

This retrospective study was conducted using the Symphony Health Solutions claims database (April 1, 2017-June 30, 2019). Patients with ≥1 medical claim with a diagnosis code representing epilepsy or seizures were assigned to the cohort with TSC if they had ≥1 medical claim for TSC; the remaining patients were assigned to the cohort without TSC. Patients in the cohort with TSC were exactly matched 1:5 on demographics to patients in the cohort without TSC. All-cause and epilepsy-related HRU, medical charges, prescription drug costs, and the use of antiepileptic drugs (AEDs) were compared between the matched cohorts over the 1-year study period.

RESULTS

A total of 2028 patients with epilepsy and TSC were matched to 10,140 patients with epilepsy but without TSC. Patients with TSC were more likely to have a diagnosis code for refractory epilepsy (38.7% vs. 10.2%, p < 0.001) and more likely to have used an AED (89.5% vs. 71.2%, p < 0.001) than patients without TSC over the study period. On average, patients with TSC received 2.1 distinct AEDs versus 1.3 distinct AEDs among patients without TSC. Compared with patients without TSC, patients with TSC had numerically but not statistically higher incidence rates of all-cause outpatient, clinic, office, and other visits; significantly lower rates of all-cause inpatient and emergency room visits (p < 0.001); and statistically significantly higher incidence rates of epilepsy-related outpatient, inpatient, office, and other visits (p ≤ 0.001). All-cause prescription drug costs were significantly higher among patients with TSC than patients without TSC (cost difference per patient: $14,179, p < 0.001). All-cause medical service charges were numerically higher for patients with TSC, but the differences were not statistically significant (charge difference per patient: $4293 for medical services, p = 0.707). Epilepsy-related costs were significantly higher for patients with TSC; the cost difference per patient was $14,639 for prescription costs (p < 0.001), and the charge difference per patient was $16,838 for medical charges (p = 0.019).

CONCLUSION

The results of this study underscore the high epilepsy-related HRU and costs incurred by patients with epilepsy and TSC relative to those incurred by patients with epilepsy but without TSC.

Rhabdomyoma association with atrioventricular septal defect in an infant: a rare coincidence

Cardiac rhabdomyoma is the most common primary heart tumor in childhood. This tumor, which is frequently associated with tuberous sclerosis complex, mostly disappears in childhood with spontaneous regression. Surgical resection is required in case of outflow obstruction and arrhythmia and when protruding to disrupt the filling of the heart cavities. There are very few case series in the literature about rhabdomyoma, whose relationship with other congenital heart defects has not been clearly verified. In this study, we report our approach to the tumor during the corrective surgery of the infant, who was diagnosed with an atrioventricular septal defect and patent ductus arteriosus, and rhabdomyoma accompanying these malformations. We treated this asymptomatic rhabdomyoma with everolimus in line with the current literature, without excision.

Outcomes of antenatally diagnosed fetal cardiac tumors: a 10-year experience at a single tertiary referral center

OBJECTIVE

The purpose of this study was to analyze the clinical and perinatal outcomes along with ultrasonographic characteristics of fetuses with a cardiac tumor.

METHODS

The data were obtained retrospectively between January 2010 and December 2019 in a tertiary referral center. The Cardiovascular Profile Score (CVPS) was used for the diagnosis of heart failure. Clinical outcomes of the cases identified in the postnatal period were analyzed.

RESULTS

Fourteen cases were evaluated with the fetal cardiac tumor. One case made the decision to terminate the pregnancy. Perinatal death was seen in 4 (30.7 %) cases out of 13 cases. In 3/14 (21.4%) cases, a solitary cardiac tumor was found while multiple cardiac tumors were found in 11/14 (78.6%) cases. All living cases 9/9 (100%) had the diagnosis of tuberous sclerosis complex (TSC). When the cases which survived were compared with the cases which died during the prenatal period, a significant difference in tumors' biggest diameters (16.44 ± 5.12 mm vs. 32.25 ± 9.28 mm; p: .011, respectively) was found. No statistically significant difference was found in the number of the tumor(s) and heart failure.

CONCLUSION

Fetal cardiac tumors can have serious perinatal mortality. The cardiac tumor size was found to be associated with perinatal mortality. The survival is not different between the cases with solitary and multiple tumors and those with and without congestive heart failure.

Tsc1 Regulates the Proliferation Capacity of Bone-Marrow Derived Mesenchymal Stem Cells

TSC1 is a tumor suppressor that inhibits cell growth via negative regulation of the mammalian target of rapamycin complex (mTORC1). TSC1 mutations are associated with Tuberous Sclerosis Complex (TSC), characterized by multiple benign tumors of mesenchymal and epithelial origin. TSC1 modulates self-renewal and differentiation in hematopoietic stem cells; however, its effects on mesenchymal stem cells (MSCs) are unknown. We investigated the impact of Tsc1 inactivation in murine bone marrow (BM)-MSCs, using tissue-specific, transgelin (Tagln)-mediated cre-recombination, targeting both BM-MSCs and smooth muscle cells. Tsc1 mutants were viable, but homozygous inactivation led to a dwarfed appearance with TSC-like pathologies in multiple organs and reduced survival. In young (28 day old) mice, Tsc1 deficiency-induced significant cell expansion of non-hematopoietic BM in vivo, and MSC colony-forming potential in vitro, that was normalized upon treatment with the mTOR inhibitor, everolimus. The hyperproliferative BM-MSC phenotype was lost in aged (1.5 yr) mice, and Tsc1 inactivation was also accompanied by elevated ROS and increased senescence. ShRNA-mediated knockdown of Tsc1 in BM-MSCs replicated the hyperproliferative BM-MSC phenotype and led to impaired adipogenic and myogenic differentiation. Our data show that Tsc1 is a negative regulator of BM-MSC proliferation and support a pivotal role for the Tsc1-mTOR axis in the maintenance of the mesenchymal progenitor pool.

Echocardiography and Newer Imaging Techniques in Diagnosis and Long-Term Follow-Up of Primary Heart Tumors in Children

Background: Primary heart tumors (PHTs) in the pediatric population are very rare and do not manifest any characteristic symptoms. Methods: A retrospective analysis of 61 cases was undertaken. Data from three centers for the years 2003–2018 were gathered. The tumors’ clinical course, location, number, hemodynamic, treatment, and follow-up were evaluated. Echocardiography was complemented with magnetic resonance imaging, computer tomography, and histopathological examination. Results: Out of 61 PHT diagnoses, 56 (91.8%) were circumstantial including all 16 (26.2%) prenatal tumors. The reasons for cardiological consultations were arrhythmia, syncopes, lowered physical performance, and murmurs. Only five patients (8.2%) were suspected of tumors based on previous symptoms of sclerosis tuberosa. Rhabdomyoma was the most frequently found PHT (60.7%). The tumors were predominantly located in the ventricles (49.1%) and intraventricular septum (14.9%) and tended to be single (70.5%). About 37.7% of patients suffered from coexistent multi-organ problems, two (3.28%) from congenital heart defects and one (1.64%) from Carney’s syndrome. Tumor resection was performed on 26 (42.7%) patients, of which 16 (61.5%) underwent total and 10 (38.5%) partial tumor resection. During the follow-up (mean 4.3 years), 54 patients (88.5%) have improved or were stable, while seven (11.5%) died. Conclusions: Primary pediatric heart tumors are diagnosed completely circumstantially, and the most common is rhabdomyoma, although arrhythmia may suggest fibroma. Diagnosis of a heart tumor in children is not synonymous with fatal prognosis, and most of them require only constant observation. Life-saving operation allows improvement, while the prognosis for malignant tumors in children is definitely unfavorable.

Description of a multidisciplinary model of care in a French cohort of adult patients with tuberous sclerosis complex

BACKGROUND

Tuberous sclerosis complex (TSC) is a rare autosomal dominant genetic disorder. Due to the various manifestations of TSC and their potential complications, a multidisciplinary care approach is recommended by consensus guidelines.

OBJECTIVES

Our study aimed to give a complete description of our TSC adult cohort and to evaluate the multidisciplinary and interdisciplinary management model.

METHODS

Data on each adult patient diagnosed with TSC, including disease manifestations, interventions and outcomes, were collected at baseline and updated annually. A multidisciplinary TSC approach with all the recommended explorations was carried out annually.

RESULTS

90 patients were enrolled in Centre Hospitalier Universitaire de Bordeaux, between January 2000 and September 2018. Median age of patients at inclusion was 37 years (range, 27-47) and 20 years old at diagnosis of TSC. Regarding the occurrence of TSC manifestations, 97% of the patients had cutaneous lesions, 89% had neurological manifestations, 83% had renal manifestations and 100% had dental lesions with pits. More than half the patients had sclerotic bone lesions (68%), TSC-associated neuropsychiatric disorders (64%) and lymphangioleiomyomatosis (59%). A TSC multidisciplinary approach was developed including a global follow-up and an evaluation of TSC targeting organs, according to the recommendations. A satisfaction survey revealed global and entire satisfaction of patients with TSC.

CONCLUSION

We obtained an accurate description of a cohort of adult patients with TSC. Our multidisciplinary approach model allowed us to provide optimal management of patients with TSC with a high level of patient satisfaction.

A case of surgically resected cardiac rhabdomyoma with progressive left ventricular outflow tract obstruction

Cardiac rhabdomyoma is the most prevalent cardiac tumors in the pediatric population, in close association with tuberous sclerosis complex. It is usually detected antenatally or postnatally by echocardiography. Clinical presentations depend greatly on the size and position of the tumor mass. Interestingly, rhabdomyoma has a propensity to regress spontaneously and is not usually operated upon, unless the patient becomes hemodynamically compromised. Herein, we report an unusual case of surgically treated cardiac rhabdomyoma in a baby boy presented at birth with a progressive enlarging intraventricular mass, complicated with left ventricular outflow tract obstruction 7 weeks later. Histopathological examination of the intracardiac mass revealed sheets of tumor cells with spider-like morphology (known as "spider cells"), confirmed the diagnosis of rhabdomyoma. Close disease monitoring of patient's hemodynamic status in a newly diagnosed cardiac rhabdomyoma is inevitable as the tumor, although rare, may progress.

Ventricular repolarization abnormalities: the electrocardiographic track of cardiac tumoural involvement in an infant with tuberous sclerosis complex. A case report

BACKGROUND

Primary cardiac tumours are rare in children. Against this backdrop, Doppler echocardiogram is the main diagnostic procedure, while electrocardiogram (ECG) usually plays a secondary role, by detecting tumoural consequences as cardiac arrhythmias and chambers overload. We describe a case where an electrocardiographic sign was the cornerstone to diagnosis and surveillance of an infant with a cardiac rhabdomyoma.

CASE SUMMARY

A female infant was referred for cardiac evaluation to elucidate an electrocardiographic abnormality, detected during investigation of seizures. She had recently been diagnosed with epilepsy and was under three different anticonvulsants for appropriate control. Cardiovascular symptoms were absent. Skin inspection revealed hypochromic macules. Respiratory and cardiovascular examinations were normal, as well as laboratorial tests and chest radiography. Electrocardiogram (ECG) showed dome-shaped ST-segment elevation in V2 and V3. Transthoracic echocardiogram unveiled a single hyper-echogenic node (0.4 cm²) in the interventricular septum. Cardiac chambers had normal size and function and Doppler analysis was also normal. No specific medication was used to treat the tumour. During follow-up, she remained free of cardiac symptoms. Eighteen months after her first visit to the cardiologist, routine clinical assessment, ECG, and transthoracic Doppler echocardiogram normal results stated the spontaneous and complete involution of the tumoural lesion.

DISCUSSION

Convex ST-segment elevation, generally related to myocardial injury, is unusual in paediatric patients. Once it occurs in asymptomatic individuals within this age bracket, exclusion of cardiac tumours is mandatory. However, data regarding the accuracy of such electrocardiographic marker in this clinical setting are still to be defined.

Everolimus for cardiac rhabdomyomas in children with tuberous sclerosis. The ORACLE study protocol (everOlimus for caRdiac rhAbdomyomas in tuberous sCLErosis): a randomised, multicentre, placebo-controlled, double-blind phase II trial

INTRODUCTION

Tuberous sclerosis complex is a rare genetic disorder leading to the growth of hamartomas in multiple organs, including cardiac rhabdomyomas. Children with symptomatic cardiac rhabdomyoma require frequent admissions to intensive care units, have major complications, namely, arrhythmias, cardiac outflow tract obstruction and heart failure, affecting the quality of life and taking on high healthcare cost. Currently, there is no standard pharmacological treatment for this condition, and the management includes a conservative approach and supportive care. Everolimus has shown positive effects on subependymal giant cell astrocytomas, renal angiomyolipoma and refractory seizures associated with tuberous sclerosis complex. However, evidence supporting efficacy in symptomatic cardiac rhabdomyoma is limited to case reports. The ORACLE trial is the first randomised clinical trial assessing the efficacy of everolimus as a specific therapy for symptomatic cardiac rhabdomyoma.

METHODS

ORACLE is a phase II, prospective, randomised, placebo-controlled, double-blind, multicentre protocol trial. A total of 40 children with symptomatic cardiac rhabdomyoma secondary to tuberous sclerosis complex will be randomised to receive oral everolimus or placebo for 3 months. The primary outcome is 50% or more reduction in the tumour size related to baseline. As secondary outcomes we include the presence of arrhythmias, pericardial effusion, intracardiac obstruction, adverse events, progression of tumour reduction and effect on heart failure.

CONCLUSIONS

ORACLE protocol addresses a relevant unmet need in children with tuberous sclerosis complex and cardiac rhabdomyoma. The results of the trial will potentially support the first evidence-based therapy for this condition.

Phakomatoses

Phakomatoses present with characteristic findings on the skin, central or peripheral nervous system, and tumors. Neurofibromatosis type 1 is the most common syndrome and is characterized by Café-au-lait macules, intertriginous freckling, Lisch nodules, and tumors including neurofibromas, malignant peripheral nerve sheath tumors, and gliomas. Tuberous Sclerosis Complex is characterized by benign hamartomas presenting with hypomelanotic macules, shagreen patches, angiofibromas, confetti lesions and tumors including cortical tubers, subependymal nodules, subependymal giant cell astrocytomas and tumors of the kidney, lung, and heart. Managing these disorders requires disease specific supportive care, tumor monitoring, surveillance for selected cancers, and treatment of comorbid conditions.

Impact of a fast free-breathing 3-T abdominal MRI protocol on improving scan time and image quality for pediatric patients with tuberous sclerosis complex

BACKGROUND

Magnetic resonance imaging (MRI) of the abdomen can be especially challenging in pediatric patients because of image quality degradation from respiratory motion. Abdominal MR protocols tailored for free-breathing children can potentially improve diagnostic image quality and reduce scan time.

OBJECTIVE

To evaluate the performance of a free-breathing 3-T MRI protocol for renal evaluation in pediatric patients with tuberous sclerosis complex (TSC).

MATERIALS AND METHODS

A single institution, Institutional Review Board-approved, retrospective database query identified pediatric TSC patients who underwent a free-breathing 3-T MR abdominal protocol including radial and respiratory-triggered pulse sequences and who also had a prior abdominal MRI on the same scanner using a traditional MR protocol utilizing signal averaging and Cartesian k-space sampling. Scan times and use of sedation were recorded. MR image quality was compared between the two protocols using a semiquantitative score for overall image quality and sharpness.

RESULTS

Forty abdominal MRI studies in 20 patients were evaluated. The mean scan time of the fast free-breathing protocol was significantly lower (mean: 42.5±9.8 min) compared with the traditional protocol (58.7±11.7 min; P=<0.001). Image sharpness was significantly improved for radial T2-weighted and T1-weighted triggered Dixon and radial T1-weighted fat-suppressed post-contrast images in the free-breathing protocol, while image quality was significantly higher on radial and Dixon T1-weighted sequences.

CONCLUSION

A free-breathing abdominal MR protocol in pediatric TSC patients decreases scan time and improves image quality and should be considered more widely for abdominal MRI in children.

Multiple cardiac rhabdomyomas in tuberous sclerosis complex: case report and review of the literature

Cardiac rhabdomyoma is a benign tumor which constitutes the most common cardiovascular feature of the tuberous sclerosis complex, a multisystem genetically determined neurocutaneous disorder. Cardiac rhabdomyomas can be detected in the prenatal ultrasound, are usually asymptomatic and spontaneously regress within the first three years of life. Less often, the tumors' size, number, and location can produce a mass effect that may lead to blood flow abnormalities or organ dysfunction (heart failure and arrhythmia). In this setting, severe morbidity, and eventually, a lethal outcome despite clinical and surgical treatment may ensue. We describe a fatal case of multiple cardiac rhabdomyomas in a newborn girl. One of the rhabdomyomas was large and unfavorably located, causing significant obstruction of the left ventricular outflow tract. The autopsy identified, in addition to cardiac rhabdomyomas, brain glioneuronal hamartomas (cortical tubers), subependymal nodules and subependymal giant cell tumors, characteristic of the tuberous sclerosis complex. The newborn's family was investigated for the presence of typical clinical symptoms of the complex and image findings showed significant phenotypical variations and a broad symptom spectrum among the family members. This interesting case underscores the variability of tuberous sclerosis complex and the importance of performing a comprehensive postmortem examination in the identification of the cause of death, especially in the setting of familial disease.

Short-term safety of mTOR inhibitors in infants and very young children with tuberous sclerosis complex (TSC): Multicentre clinical experience

OBJECTIVE

To evaluate the safety of mTOR inhibitors (sirolimus or everolimus) in infants and very young children with tuberous sclerosis complex (TSC) under two years of age.

METHODS

Study design was retrospective to capture medical record data from 52 international TSC Centres who initiated treatment with sirolimus or everolimus in TSC children before the age of two years. Data collection included demographic and clinical information including reason(s) for initiating treatment with mTOR inhibitors, treatment duration, dosing, and corresponding serum trough levels, response to treatment, and adverse events (AE).

RESULTS

19 of 52 (37%) TSC Centres reported treatment of at least one child with TSC under the age of two years with everolimus or sirolimus. Treatment-related data were provided for 45 patients meeting inclusion criteria. Everolimus was utilised 87% of the time, compared to 24% for sirolimus (5 subjects, 11%, were treated separately with both). Refractory epilepsy (45%) was the most common primary reason for initiating treatment and treatment was initiated on average at 11.6 ± 7.6 months of age. At least one AE, suspected or definitely treatment-related, occurred in 35 of 45 (78%) treated subjects. Most AEs were mild (Grade 1) or moderate (Grade 2) in severity and most commonly related to infections. Severe AE (Grade 3) was reported in 7 subjects (20%) and no life-threatening AE (Grade 4) or death/disability (Grade 5) was reported. Treatment was discontinued due to an AE in 9 of 45 (20%).

CONCLUSIONS

Everolimus, and to a lesser extent sirolimus, are increasingly being used to treat TSC infants and very young children for multiple TSC-associated clinical indications. While AEs were common, most were not severe and did not prevent continued treatment in the majority of this younger population.

Neurocutaneous Disorders

PURPOSE OF REVIEW

This article presents an up-to-date summary of the genetic etiology, diagnostic criteria, clinical features, and current management recommendations for the most common neurocutaneous disorders encountered in clinical adult and pediatric neurology practices.

RECENT FINDINGS

The phakomatoses are a phenotypically and genetically diverse group of multisystem disorders that primarily affect the skin and central nervous system. A greater understanding of the genetic and biological underpinnings of numerous neurocutaneous disorders has led to better clinical characterization, more refined diagnostic criteria, and improved treatments in neurofibromatosis type 1, Legius syndrome, neurofibromatosis type 2, Noonan syndrome with multiple lentigines, tuberous sclerosis complex, Sturge-Weber syndrome, and incontinentia pigmenti.

SUMMARY

Neurologists require a basic knowledge of and familiarity with a wide variety of neurocutaneous disorders because of the frequent involvement of the central and peripheral nervous systems. A simple routine skin examination can often open a broad differential diagnosis and lead to improved patient care.

Rapid Regression of Prenatally Identified Intrapericardial Giant Rhabdomyomas with Sirolimus

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Giant cardiac rhabdomyomas were identified on fetal echocardiography.

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The rhabdomyomas were unusually located in the pericardial space.

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Rapid regression and hemodynamic improvement were seen with sirolimus therapy.

Tuberous sclerosis complex: review based on new diagnostic criteria

Tuberous sclerosis complex is a multisystemic, autosomal dominant genetic disorder with complete penetrance, that can evolve with hamartomas in multiple organs, such as skin, central nervous system, kidney and lung. Due to the wide phenotypic variability, the disease is often not recognized. Tuberous sclerosis complex affects one in 10,000 newborns and most patients are diagnosed during the first 15 months of life. The diagnostic criteria for tuberous sclerosis were reviewed in 2012, at the second International Tuberous Sclerosis Complex Consensus Conference. The diagnosis is based on genetic criteria, by the identification of inactivating pathogenic mutation of tumor suppressor genes TSC1 and TSC2, and clinical criteria, including cutaneous, renal, pulmonary, cardiac and neurological manifestations. The treatment of tuberous sclerosis complex consists, mainly, in management of the symptoms caused by hamartomas and in prevention of organ failure. Multidisciplinary approach is recommended, in order to obtain better clinical outcomes.

A novel TSC2 missense variant associated with a variable phenotype of tuberous sclerosis complex: case report of a Chinese family

Background

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder characterized by the development of hamartomas in multiple organs, including the brain, heart, skin, kidney, lung and retina. A diagnosis of TSC is established with a recently revised clinical/radiological set of criteria and/or a causative mutation in TSC1 or TSC2 gene.

Case presentation

We report a Chinese TSC family with two siblings presenting with multiple hypomelanotic macules, cardiac rhabdomyomas and cortical tubers associated with a small subependymal nodule. The older child had seizures. A novel heterozygous missense variant in the TSC2 gene (c.899G > T, p.G300 V) was identified and shown to be inherited from their father as well as paternal grandfather, both of whom presented with variable TSC-associated signs and symptoms.

Conclusion

We identified a novel heterozygous TSC2 variant c.899G > T as the causative mutation in a Chinese family with TSC, resulting in wide intrafamilial phenotypic variability. Our study illustrates the importance of clinical evaluation and genetic testing for family members of the patient affected with TSC.

Primary cardiac tumors associated with genetic syndromes: a comprehensive review

Various cardiac tumors occur in the setting of a genetic syndrome such as myxomas in Carney complex and rhabdomyomas in tuberous sclerosis. Tumor biology can be different in syndromic forms, and on imaging children sometimes demonstrate additional manifestations of the underlying syndrome. We discuss the imaging appearance of cardiac tumors occurring in the framework of a genetic syndrome, the findings that suggest an underlying syndrome, and the impact on management.

Punch-out lesion following regression of a large left ventricular outflow rhabdomyoma

Abstracts We report the case of a patient with rhabdomyoma of the left ventricular outflow tract, causing severe obstruction at birth. The tumour regressed completely by 6 years of age, leaving a punch-out lesion. The potential for spontaneous regression of these tumours and the formation of a myocardial lesion following rhabdomyoma regression are discussed.

Early Detection of Tuberous Sclerosis Complex: An Opportunity for Improved Neurodevelopmental Outcome

BACKGROUND

Tuberous sclerosis complex (TSC) is an autosomal dominant condition associated with epilepsy, benign tumors, and variable neurodevelopmental outcomes. The diagnosis is most commonly made after epilepsy onset, although a proportion are diagnosed prenatally. Presymptomatic or early treatment with agents such as vigabatrin offers the hope of improved neurodevelopmental outcome. Therefore early diagnosis, before the onset of seizures, is important. In a cohort of children with TSC, we evaluated the age and mode of initial presentation, assessed the neurocognitive and epilepsy outcome, and analyzed whether those diagnosed before the onset of seizures have a different outcome compared with those diagnosed postseizures.

METHODS

We reviewed patients at the TSC clinic at Sydney Children's Hospital who were born between 2001 and 2015.

RESULTS

A total of 74 patients were identified: 34 (46%) diagnosed preseizure (21 prenatally) and 40 (54%) postseizure. In the preseizure cohort, 77% presented with cardiac rhabdomyoma(s) and 72% developed seizures. The postseizure cohort had more severe epilepsy, requiring more antiepileptic drugs for seizure control (median five, compared with three in the preseizure cohort [P = 0.01]). Developmental disability occurred in 65% of the preseizure cohort compared with 72% of the postseizure cohort. Severe developmental disability most often occurred in children who had their first seizure before age 12 months.

CONCLUSION

Children who are diagnosed with TSC before the onset of seizures have less severe epilepsy and better developmental outcome.

Tuberous Sclerosis Complex: A Review

Tuberous sclerosis complex (TSC) is a neurocutaneous syndrome that can present at any age and can affect multiple organ systems. This disorder is usually identified in infants and children based on characteristic skin lesions, seizures, and cellular overgrowth or hamartomas in the heart, brain, and kidneys. Tuberous sclerosis complex is a genetic disorder caused by a mutation in either the TSC1 or TSC2 gene leading to dysfunction of hamartin or tuberin, respectively. Hamartin and tuberin form a protein complex that helps regulate cellular hyperplasia. Accurate diagnosis is essential in implementing appropriate surveillance and treatment to patients with this disorder. Specific guidelines for diagnosis, surveillance, and management have been proposed by the International Tuberous Sclerosis Complex Consensus Group. Treatment of tuberous sclerosis complex is in part symptomatic; however, for certain clinical manifestations, specific treatments may be indicated. [Pediatr Ann. 2017;46(4):e166-e171.].

Successful use of sirolimus for refractory atrial ectopic tachycardia in a child with cardiac rhabdomyoma

Cardiac rhabdomyomas are common in tuberous sclerosis. We report a child who developed rhabdomyoma related arrhythmia refractory to antiarrhythmic drug therapy. Reversion of the atrial ectopic tachycardia was achieved with mammalian target of rapamycin pathway (mTOR) inhibitor sirolimus. As per our knowledge, this is the first time that sirolimus has been successfully used in this setting.

Manifestations of Tuberous Sclerosis Complex: The Experience of a Provincial Clinic

BACKGROUND

Tuberous sclerosis complex (TSC) is a neurocutaneous disorder with a wide spectrum of manifestations. Recent consensus recommendations stress the importance of multidisciplinary management of children with TSC. The objective of this study was to examine the manifestations of TSC at a large referral centre to determine the care needs of this population.

METHODS

A retrospective, systematic chart review was performed of children with TSC managed at British Columbia Children's Hospital. Patients were identified through epilepsy and clinical neurophysiology databases.

RESULTS

The study population comprised 81 patients, born between 1987 and 2014, who were a median of 10 years (range, 0.2-23.2) at most recent follow-up. Epilepsy occurred in 91% of patients, including 32% with a history of infantile spasms. Nineteen patients underwent epilepsy surgery, nine (47%) of whom were seizure-free at most recent follow-up. Overall, 61% of epilepsy patients had been seizure-free for at least 1 year at the time of last follow-up. Neuropsychiatric disorders were diagnosed in 49% of children, with autism (25%), attention deficit hyperactivity order (19%) and anxiety (16%) being the most common. Cardiac rhabdomyomata occurred in 35% of children and renal angiomyolipomas were seen in 43%. A total of 91% had skin manifestations.

CONCLUSION

This study outlines the multisystem manifestations of TSC, observed through a large pediatric referral center. Epilepsy and neuropsychiatric disorders are the major source of morbidity in this age group and provide many challenges to the treating clinician. Because a subset of the study population is still quite young, the prevalence of neuropsychiatric disorders is likely underestimated.

Regression of Neonatal Cardiac Rhabdomyoma in Two Months Through Low-Dose Everolimus Therapy: A Report of Three Cases

Cardiac rhabdomyoma (CR) is the most common cardiac tumor in newborns. Approximately 75% of cases are associated with tuberous sclerosis complex. Although these tumors usually spontaneously regress after 2 years of age, they can be life-threatening when they obstruct major cardiac inflow or outflow pathways. Everolimus is an inhibitor of the mammalian target of rapamycin, reducing its production of the proteins harmartin and tuberin. Everolimus has demonstrated a remarkable suppression effect in children with tuberous sclerosis complex at doses of 4.7-5.6 mg/M²/day and serum trough levels of 5-15 ng/mL. Since 2012, five case reports of neonates with CR have also reported the tumor-regressing effect of everolimus. However, the optimal dosage for neonates is still unknown. Over the past 2 years, we have deliberately used a low dose everolimus regimen (0.3-0.67 mg/M²/day) in three neonates with large CRs, in an effort to maintain serum trough levels at 3-7 ng/mL. In all three cases, the tumors regressed smoothly within 2 months. Regarding the drug's side effect of predisposing patients to infection, we observed that adenovirus pneumonia occurred in one case at 3 months of age, and chicken pox occurred in another case at 9 months of age; both recovered smoothly. Our three cases of neonatal CR demonstrate that a low-dose everolimus regimen is an effective treatment for tumor regression.

Is mTOR Inhibitor Good Enough for Treatment All Tumors in TSC Patients?

Tuberous sclerosis complex (TSC) is an autosomal dominant and multi-system genetic disorder in humans. TSC affects around 25,000 to 40,000 individuals in the United States and about 1 to 2 million individuals worldwide, with an estimated prevalence of one in 6,000 newborns. TSC occurs in all races and ethnic groups, and in both genders. TSC is caused by defects or mutations in two genes, TSC1 and TSC2. Loss of TSC1/TSC2 leads to dysregulation of mTOR, resulting in aberrant cell differentiation and development, and abnormal enlargement of cells. TSC is characterized by the development of benign and/or malignant tumors in several organs including renal/liver angiomyolipomas, facial angiofibroma, lymphangiomyomatosis, cardiac rhabdomyomas, retinal astrocytic, renal cell carcinoma, and brain subependymal giant cell astrocytomas (SEGA). In addition, TSC disease causes disabling neurologic disorders, including epilepsy, mental retardation and autism. Particularly problematic are the development of renal angiomyolipomas, which tend to be larger, bilateral, multifocal and present at a younger age compared with sporadic forms. In addition, SEGA block the flow of fluid within the brain, causing a buildup of fluid and pressure that leads to blurred vision and seizures. In the current review, we describe the pathology of TSC disease in key organs and summarize the use of mTOR inhibitors to treat tumors in TSC patients.

Systemic disease manifestations associated with epilepsy in tuberous sclerosis complex

OBJECTIVE

Epilepsy is one of the most disabling symptoms of tuberous sclerosis complex (TSC) and is a leading cause of morbidity and mortality in affected individuals. The relationship between systemic disease manifestations and the presence of epilepsy has not been thoroughly investigated. This study utilizes a multicenter TSC Natural History Database including 1,816 individuals to test the hypothesis that systemic disease manifestations of TSC are associated with epilepsy.

METHODS

Univariate analysis was used to identify patient characteristics (e.g., age, gender, race, and TSC mutation status) associated with the presence of epilepsy. Individual logistic regression models were built to examine the association between epilepsy and each candidate systemic or neurologic disease variable, controlling for the patient characteristics found to be significant on univariate analysis. Finally, a multivariable logistic regression model was constructed, using the variables found to be significant on the individual analyses as well as the patient characteristics that were significant on univariate analysis.

RESULTS

Nearly 88% of our cohort had a history of epilepsy. After adjusting for age, gender, and TSC mutation status, multiple systemic disease manifestations including cardiac rhabdomyomas (odds ratio [OR] 2.3, 95% confidence interval [CI] 1.3-3.9, p = 0.002), retinal hamartomas (OR 2.1, CI 1.0-4.3, p = 0.04), renal cysts (OR 2.1, CI 1.3-3.4, p = 0.002), renal angiomyolipomas (OR 3.0, CI 1.8-5.1, p < 0.001), shagreen patches (OR 1.7, CI 1.0-2.7, p = 0.04), and facial angiofibromas (OR 1.7, CI 1.1-2.9, p = 0.03) were associated with a higher likelihood of epilepsy. In the multivariable logistic regression model, cardiac rhabdomyomas (OR 1.9, CI 1.0-3.5, p = 0.04) remained significantly associated with the presence of epilepsy.

SIGNIFICANCE

The identification of systemic disease manifestations such as cardiac rhabdomyomas that confer a higher risk of epilepsy development in TSC could contribute to disease prognostication and assist in the identification of individuals who may receive maximal benefit from potentially novel, targeted, preventative therapies.

Myocardial Fatty Foci in Tuberous Sclerosis Complex: Imaging Findings

Tuberous sclerosis complex (TSC) is a rare autosomal dominant genetic syndrome. The hallmark of the disease is multiple hamartomatous lesions in multiple organ systems. Common cardiac manifestations of TSC are rhabdomyomas, which are a benign tumor of striated muscle. In some patients with TSC, myocardial fatty foci (MFF) deposition has been described with or without the presence of rhabdomyomas.

We present the case of a 24-year-old female with TSC and refractory seizures, who was evaluated with cardiac magnetic resonance (CMR) for an intracardiac right ventricular mass thought to be rhabdomyoma on echocardiography and for multiple areas of myocardial fatty deposition. Myocardial fatty deposition is a common finding in patients at cardiac imaging. In patients with TSC, it is critical that fatty deposits and lipomas are clearly distinguished from rhabdomyoma. CMR is an integral part of characterizing cardiac masses as it has superior soft tissue characterization and a wider field of view compared to echocardiography. A positive correlation has been shown between the number of MFF and the degree of extracardiac tuberous sclerosis (TS) manifestations suggesting that MFF may indicate more severe multiorgan disease in patients with TSC.

Cardiac MR is superior to echocardiogram in evaluating and distinguishing intracardiac lipomas and fatty deposits from rhabdomyomas. Published studies have indicated that in patients with TSC, the presence of MFF correlates with the severity of multiorgan disease as was seen in our case.

Rapamycin and rapalogs for tuberous sclerosis complex

BACKGROUND

Previous studies have shown potential benefits of rapamycin or rapalogs for treating people with tuberous sclerosis complex. Although everolimus (a rapalog) is currently approved by the FDA (U.S. Food and Drug Administration) and the EMA (European Medicines Agency) for tuberous sclerosis complex-associated renal angiomyolipoma and subependymal giant cell astrocytoma, applications for other manifestations of tuberous sclerosis complex have not yet been established. A systematic review is necessary to establish the clinical value of rapamycin or rapalogs for various manifestations in tuberous sclerosis complex.

OBJECTIVES

To determine the effectiveness of rapamycin or rapalogs in people with tuberous sclerosis complex for decreasing tumour size and other manifestations and to assess the safety of rapamycin or rapalogs in relation to their adverse effects.

SEARCH METHODS

Relevant studies were identified by authors from the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, and clinicaltrials.gov. Relevant resources were also searched by the authors, such as conference proceedings and abstract books of conferences, from e.g. the Tuberous Sclerosis Complex International Research Conferences, other tuberous sclerosis complex-related conferences and the Human Genome Meeting. We did not restrict the searches by language as long as English translations were available for non-English reports.Date of the last searches: 14 March 2016.

SELECTION CRITERIA

Randomized or quasi-randomized studies of rapamycin or rapalogs in people with tuberous sclerosis complex.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two authors using standard acquisition forms. The data collection was verified by one author. The risk of bias of each study was independently assessed by two authors and verified by one author.

MAIN RESULTS

Three placebo-controlled studies with a total of 263 participants (age range 0.8 to 61 years old, 122 males and 141 females, with variable lengths of study duration) were included in the review. We found high-quality evidence except for response to skin lesions which was judged to be low quality due to the risk of attrition bias. Overall, there are 175 participants in the treatment arm (rapamycin or everolimus) and 88 in the placebo arm. Participants all had tuberous sclerosis complex as proven by consensus diagnostic criteria as a minimum. The quality in the description of the study methods was mixed, although we assessed most domains as having a low risk of bias. Blinding of treatment arms was successfully carried out in all of the studies. However, two studies did not report allocation concealment. Two of the included studies were funded by Novartis Pharmaceuticals.Two studies (235 participants) used oral (systemic) administration of everolimus (rapalog). These studies reported response to tumour size in terms of the number of individuals with a reduction in the total volume of tumours to 50% or more relative to baseline. Significantly more participants in the treatment arm (two studies, 162 participants, high quality evidence) achieved a 50% reduction in renal angiomyolipoma size, risk ratio 24.69 (95% confidence interval 3.51 to 173.41) (P = 0.001). For the sub-ependymal giant cell astrocytoma, our analysis of one study (117 participants, high quality evidence) showed significantly more participants in the treatment arm achieved a 50% reduction in tumour size, risk ratio 27.85 (95% confidence interval 1.74 to 444.82) (P = 0.02). The proportion of participants who showed a skin response from the two included studies analysed was significantly increased in the treatment arms, risk ratio 5.78 (95% confidence interval 2.30 to 14.52) (P = 0.0002) (two studies, 224 participants, high quality evidence). In one study (117 participants), the median change of seizure frequency was -2.9 in 24 hours (95% confidence interval -4.0 to -1.0) in the treatment group versus -4.1 in 24 hour (95% confidence interval -10.9 to 5.8) in the placebo group. In one study, one out of 79 participants in the treatment group versus three of 39 in placebo group had increased blood creatinine levels, while the median percentage change of forced expiratory volume at one second in the treatment arm was -1% compared to -4% in the placebo arm. In one study (117 participants, high quality evidence), we found that those participants who received treatment had a similar risk of experiencing adverse events compared to those who did not, risk ratio 1.07 (95% confidence interval 0.96 - 1.20) (P = 0.24). However, as seen from two studies (235 participants, high quality evidence), the treatment itself led to significantly more adverse events resulting in withdrawal, interruption of treatment, or reduction in dose level, risk ratio 3.14 (95% confidence interval 1.82 to 5.42) (P < 0.0001).One study (28 participants) used topical (skin) administration of rapamycin. This study reported response to skin lesions in terms of participants' perception towards their skin appearance following the treatment. There was a tendency of an improvement in the participants' perception of their skin appearance, although not significant, risk ratio 1.81 (95% confidence interval 0.80 to 4.06, low quality evidence) (P = 0.15). This study reported that there were no serious adverse events related to the study product and there was no detectable systemic absorption of the rapamycin during the study period.

AUTHORS' CONCLUSIONS

We found evidence that oral everolimus significantly increased the proportion of people who achieved a 50% reduction in the size of sub-ependymal giant cell astrocytoma and renal angiomyolipoma. Although we were unable to ascertain the relationship between the reported adverse events and the treatment, participants who received treatment had a similar risk of experiencing adverse events as compared to those who did not receive treatment. Nevertheless, the treatment itself significantly increased the risk of having dose reduction, interruption or withdrawal. This supports ongoing clinical applications of oral everolimus for renal angiomyolipoma and subependymal giant cell astrocytoma. Although oral everolimus showed beneficial effect on skin lesions, topical rapamycin only showed a non-significant tendency of improvement. Efficacy on skin lesions should be further established in future research. The beneficial effects of rapamycin or rapalogs on tuberous sclerosis complex should be further studied on other manifestations of the condition.

Cognitive impairment and spontaneous epilepsy in rats with malformations of cortical development

PURPOSE

To examine the cognition, spontaneous epilepsy, and electroencephalography (EEG) characteristics of rats with malformations of cortical development (MCD) and their use as an animal model for investigating the pathogenesis of intractable epilepsy and screening novel antiepileptic drugs.

METHODS

An epileptic rat model of MCD was established with the F1 generation of pregnant rats after X-irradiation with 175 cGy (Group L), 195 cGy (Group M), or 215 cGy (Group H). Long-term video-EEG monitoring was used to record the seizures in the rats with MCD. Cognition was assessed with the Morris water maze. The EEGs were recorded and analyzed in the frontal and parietal lobes and hippocampi of adult rats. Finally, the brain tissues were processed for Nissl staining.

RESULTS

The model groups exhibited markedly prolonged escape latencies and distinct decrements in the percent distance traveled in the target quadrant and platform-crossing frequency. These findings were dose-dependent. Frequent interictal epileptiform discharges were observed in the frontal and parietal lobes and hippocampi of adult rats, and their incidences were markedly higher in the model groups compared with that in the normal controls, with Group M having the highest incidence. Spontaneous seizures were observed in the model groups (mean incidence, 46.7%). The daily mean frequency of seizures and the incidence of spontaneous seizures were highest in Group M. Nissl staining revealed a dose-dependent pattern of hippocampal abnormalities, cortical and subcortical nodular heterotopia, and callosal agenesis in the model groups.

CONCLUSION

The 195 cGy dose was most appropriate for establishing an epileptic model of MCD with X-irradiation.