Cutaneous venous malformations in familial cerebral cavernomatosis caused by KRIT1 gene mutations

Brain and/or Spinal Cord Tumors Accompanied with Other Diseases or Syndromes

Several medical conditions that interest both the brain and the spinal cord have been described throughout the history of medicine. Formerly grouped under the term Phacomatosis because lesions of the eye were frequently encountered or genodermatosis when typical skin lesions were present, these terms have been progressively discarded. Although originally reported centuries ago, they still represent a challenge for their complexity of cure. Nowadays, with the introduction of advanced genetics and the consequent opportunity of whole-genome sequencing, new single cancer susceptibility genes have been identified or better characterized; although there is evidence that the predisposition to a few specific tumor syndromes should be accounted to a group of mutations in different genes while certain syndromes appeared to be manifestations of different mutations in the same gene adding supplementary problems in their characterization and establishing the diagnosis. Noteworthy, many syndromes have been genetically determined and well-characterized, accordingly in the near future, we expect that new targeted therapies will be available for the definitive cure of these syndromes and other gliomas (Pour-Rashidi et al. in World Neurosurgery, 2021). The most common CNS syndromes that will be discussed in this chapter include neurofibromatosis (NF) types 1 and 2, von Hippel-Lindau (VHL) disease, and tuberous sclerosis complex (TSC), as well as syndromes having mostly extra-neural manifestations such as Cowden, Li-Fraumeni, Turcot, and Gorlin syndromes.

Magnetic Resonance Imaging of Multiple Cerebral and Spinal Cavernous Malformations of a Patient with Dementia and Tetraparesis

Cavernomas are rare cerebrovascular malformations that usually occur in sporadic forms with solitary lesions located most often in the hemispheric white matter, but also in the infratentorial or spinal region. Multiple lesions at different CNS levels are considered a hallmark for the familial form of the disease. The diagnostic modality of choice for cerebral cavernous malformations (CCMs) is magnetic resonance imaging (MRI). We present an intriguing case of a 65-year-old male admitted to our hospital with tetraparesis and cognitive impairment where highly sensitive MRI sequences identified many cerebral cavernous lesions at the supra-, infratentorial and cervical–thoracic spine levels, some of them with recent signs of bleeding in a patient with oral anticoagulant therapy due to atrial fibrillation. The mechanism of cognitive impairment in this patient is most probably the interruption of strategic white matter tracts, as it is known to happen in other subcortical vascular pathologies. MRI can be helpful not only in mapping the anatomical distribution of lesions, but also in weighing the risks and making decisions regarding whether or not to continue oral anticoagulant therapy.

Clinical, neuroradiological and genetic findings in a cohort of patients with multiple Cerebral Cavernous Malformations

Cerebral cavernous malformations (CCM) consist of clusters of irregular dilated capillaries and represent the second most common type of vascular malformation affecting the central nervous system. CCM might be asymptomatic or cause cerebral hemorrhage, seizures, recurrent headaches and focal neurologic deficits. Causative mutations underlining CCM have been reported in three genes: KRIT1/CCM1, MGC4607/CCM2 and PDCD10/CCM3. Therapeutic avenues are limited to surgery. Here we present clinical, neuroradiological and molecular findings in a cohort of familial and sporadic CCM patients. Thirty subjects underwent full clinical and radiological assessment. Molecular analysis was performed by direct sequencing and MLPA analysis. Twenty-eight of 30 subjects (93%) experienced one or more typical CCM disturbances with cerebral/spinal hemorrhage being the most common (43%) presenting symptom. A molecular diagnosis was achieved in 87% of cases, with three novel mutations identified. KRIT1/CCM1 patients displayed higher risk of de novo CCMs appearance and bleedings. Magnetic Resonance Imaging (MRI) showed that infratentorial region was more frequently affected in mutated subjects while brainstem was often spared in patients with negative genetic testing.

Assessing the association of common genetic variants in EPHB4 and RASA1 with phenotype severity in familial cerebral cavernous malformation

Background

To investigate whether common variants in EPHB4 and RASA1 are associated with cerebral cavernous malformation (CCM) disease severity phenotypes, including intracranial hemorrhage (ICH), total and large lesion counts.

Methods

Familial CCM cases enrolled in the Brain Vascular Malformation Consortium were included (n = 338). Total lesions and large lesions (≥5 mm) were counted on MRI; clinical history of ICH at enrollment was assessed by medical records. Samples were genotyped on the Affymetrix Axiom Genome‐Wide LAT1 Human Array. We tested the association of seven common variants (three in EPHB4 and four in RASA1) using multivariable logistic regression for ICH (odds ratio, OR) and multivariable linear regression for total and large lesion counts (proportional increase, PI), adjusting for age, sex, and three principal components. Significance was based on Bonferroni adjustment for multiple comparisons (0.05/7 variants = 0.007).

Results

EPHB4 variants were not significantly associated with CCM severity phenotypes. One RASA1 intronic variant (rs72783711 A>C) was significantly associated with ICH (OR = 1.82, 95% CI = 1.21–2.37, p = 0.004) and nominally associated with large lesion count (PI = 1.17, 95% CI = 1.03–1.32, p = 0.02).

Conclusion

A common RASA1 variant may be associated with ICH and large lesion count in familial CCM. EPHB4 variants were not associated with any of the three CCM severity phenotypes.

Tuberous sclerosis with negative genetic testing and multiple cerebral cavernomas: A new association (Case report)

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder with multisystemic involvement usually resulting from mutations in the tuberous sclerosis 1 (TSC1) or TSC2 genes. However, 10 to 25% of patients do not exhibit these mutations. Cerebral cavernous malformations (CCMs) are capillary-venous malformations that can be asymptomatic or cause variable neurological manifestations, including seizures. Familial CCMs are recognized. In both conditions, specific dermatological lesions are associated. We present the case of a 31-year-old female with TSC diagnosed at the age of 18 years who presented with negative genetic testing. She was admitted to our department in 2019 for a sudden increased frequency of focal seizures. Patient examination revealed multiple facial and intraoral angiofibroma, diplopia, right hemihypoesthesia, brisk deep tendon reflexes, and distal leg paresthesia. VideoEEG indicated a frontal paramedian epileptogenic focus. Cerebral magnetic resonance imaging (MRI) and angioMRI identified multiple fronto-parietal cortical tubers, as well as multiple CCMs, with evidence of bleeding in one. Under antiepileptic drug (AED) and mTOR inhibitor treatment, the seizure frequency significantly improved in a short period of time. This is the first reported case of tuberous sclerosis with negative genetic testing associated with multiple cerebral cavernoma. Such complex patients require multidisciplinary management and detailed genetic testing for increasing knowledge on neuro-cutaneous disorders.

Blue Rubber Bleb Nevus Syndrome With Multiple Cavernoma-Like Lesions on MRI: A Familial Case Report and Literature Review

Blue rubber bleb nevus syndrome (BRBNS), also called Bean's syndrome, is a rare disease associated with multiple venous malformations in the skin and gastrointestinal (GI) tract. Dermatological lesions, which are the first clinically visible manifestations, appear as skin-colored compressible protuberances or as dark-blue venous nodules, rubbery in consistency. Central nervous system (CNS) manifestations are rare, variable, non-specific, and tend to occur late in the disease, mainly reported as seizures and focal neurological deficits secondary to compression. Most cases occur sporadically, however, an autosomal dominant inheritance pattern has been reported. A 74-year-old male with history of focal epilepsy secondary to possible neurocysticercosis presented at the emergency department due to sudden onset of aphasia, left central facial paralysis, and dysphagia secondary to catastrophic intracerebral hemorrhage. Cerebral MRI showed multiple cerebral cavernous malformations (CCM)-like lesions and, on the general exploration, multiple dark-blue nodules, rubbery in consistency. One week later he died due to complicated pneumonia; a brain autopsy was performed showing multiple vascular malformations. His son had a history of focal epilepsy presumed to be related to neurocysticercosis. He had the same skin lesions and brain MRI pattern. Histological analysis of the skin lesions of the two cases showed venous vascular malformations. A non-systematic review was carried out, in which all case reports of blue nevus syndrome with neurological manifestations in adults were included.

Cutaneous findings of familial cerebral cavernous malformation syndrome due to the common Hispanic mutation

Familial cerebral cavernous malformations due to the common Hispanic mutation (FCCM1-CHM) is an endemic condition among the Hispanic population of the Southwestern United States associated with significant morbidity and mortality. Cutaneous vascular malformations (CVMs) can be found in individuals with FCCM1-CHM, but their morphology, prevalence, and association with cerebral cavernous malformations (CCMs) has not been well characterized. A cross-sectional study of 140 individuals with confirmed FCCM1-CHM was performed with statistical analyses of CVM, CCM, and patient characteristics. We then compared these findings to other cohorts with Familial cerebral cavernous malformations (FCCM) due to other mutations. We observed a higher overall prevalence and a different predominant morphological subtype of CVM compared to previous FCCM cohorts. While the number of CVMs was not a reliable indicator of the number of CCMs present, each person with one or more CVMs had evidence of central nervous system (CNS) disease. Awareness of the morphology of these cutaneous lesions can aid in the diagnosis of individuals with FCCM-CHM in Hispanic patients or those with family history of CCM.

Vertebral Intraosseous Vascular Malformations in a Familial Cerebral Cavernous Malformation Population: Prevalence, Histologic Features, and Associations With CNS Disease

OBJECTIVE. The purpose of this study was to investigate whether MRI-typical and MRI-atypical intraosseous vascular malformations are associated with familial cerebral cavernous malformation (FCCM). MATERIALS AND METHODS. In a retrospective matched case-control study, two radiologists reviewed the spinal imaging, both CT and MRI, of 22 patients with FCCM seen between 2006 and 2017 and of age- and sex-matched control subjects for MRI-typical and MRI-atypical intraosseous vascular malformations. Quantitative analysis of lesions identified included vertebral level, size, and number of lesions. Pathologic samples from two lesions were analyzed for histologic and immunohistochemical features. Whether the presence of typical, atypical, and total intraosseous vascular malformations differed between patients and control subjects was tested. For patients with complete spinal imaging, whether intraosseous vascular malformations were associated with age, sex, brain lesion count, and spinal lesion count was also tested. RESULTS. MRI-atypical intraosseous vertebral malformations were more commonly present in patients with FCCM (p = 0.003). Sixteen lesions were found in nine patients and none in the control group. The numbers of MRI-typical intraosseous vascular malformations were similar between patients and control subjects (p = 0.480). Age was associated with typical intraosseous vascular malformations (p = 0.027), though not with atypical malformations. MRI-atypical malformations were larger (mean diameter double) than MRI-typical malformations (p = 0.023). Histologic analysis of two lesions from different patients with pathologic collapse revealed the same histologic features consistent with combined capillary-venous malformations. CONCLUSION. Vertebral capillary-venous malformations (MRI-atypical intraosseous vascular malformations) are common in patients with FCCM and may have a more aggressive clinical course than MRI-typical malformations.

Developmental venous anomalies and brainstem cavernous malformations: a proposed physiological mechanism for haemorrhage

The incidental diagnosis of both developmental venous anomalies (DVAs) and cavernous malformations (CMs) in the central nervous system is increasing with improved imaging techniques. While classically silent diseases, these cerebrovascular pathologies can follow an aggressive course, particularly when present in the brainstem. In the last decade, substantial research has focussed on KRIT1-mediated tight junction gene expression and their role in CM development. However, our understanding of the physiologic conditions precipitating symptomatic CM development or CM haemorrhage with and without concomitant DVAs, remains lacking. The only established risk factor for CM haemorrhage is a previous history of haemorrhage, and literature currently reports trauma as the only precipitant for symptomatic events. While plausible, this occurs in a minority, with many patients experiencing occult events. This manuscript presents a hypothesis for symptomatic CM events by first discussing the anatomical pathways for intracranial venous outflow via the internal jugular veins (IJV) and vertebral venous plexus (VVP), then exploring the role of venous flow diversion away from the IJVs under physiologic stress during dynamic postural shift. The resultant increase in intracranial venous pressure can exacerbate normal and pre-existing structural DVA pathologies, with repeated exposure causing symptomatic or CM-inducing events. This pathophysiological model is considered in the context of the role of the autonomic nervous system (ANS) in postural intracranial venous outflow diversion, and how this may increase the risk of DVA or CM events. It is hoped that this hypothesis invokes further investigation into precipitants for DVA or CM events and their sequela and, also, furthers the current knowledge on pathophysiological development of DVAs and CMs.

Hereditary Multiple Cerebral Cavernous Malformations Associated with Wilson Disease and Multiple Lipomatosis

We report on a patient with 2 Mendelian diseases-symptomatic multiple familial cerebral cavernous malformations (FCCMs) and Wilson disease. Genetic analysis revealed single nucleotide polymorphisms in genes CCM2 and CCM3, associated with cavernous malformations, and homozygote mutation in the ATP7B gene, responsible for Wilson disease. FCCMs were symptomatic in 3 generations. The patient also had multiple lipomatosis, which is suggested to be a familial syndrome. In recent years there has been an increasing amount of publications linking FCCMs with other pathology, predominantly with extracranial and intracranial mesenchymal anomalies. The present study is the description of an unusual association between 2 independent hereditary diseases of confirmed genetic origin-a combination that has not been described previously.

Familial Cerebral Cavernous Malformations Are Associated with Adrenal Calcifications on CT Scans: An Imaging Biomarker for a Hereditary Cerebrovascular Condition

Purpose To determine if adrenal calcifications seen at computed tomography (CT) are associated with familial cerebral cavernous malformations (fCCMs) in carriers of the CCM1 Common Hispanic Mutation. Materials and Methods This study was approved by the institutional review board. The authors retrospectively reviewed abdominal CT scans in 38 patients with fCCM, 38 unaffected age- and sex-matched control subjects, and 13 patients with sporadic, nonfamilial cerebral cavernous malformation (CCM). The size, number, and laterality of calcifications and the morphologic characteristics of the adrenal gland were recorded. Brain lesion count was recorded from brain magnetic resonance (MR) imaging in patients with fCCM. The prevalence of adrenal calcifications in patients with fCCM was compared with that in unaffected control subjects and those with sporadic CCM by using the Fisher exact test. Additional analyses were performed to determine whether age and brain lesion count were associated with adrenal findings in patients with fCCM. Results Small focal calcifications (SFCs) (≤5 mm) were seen in one or both adrenal glands in 19 of the 38 patients with fCCM (50%), compared with 0 of the 38 unaffected control subjects (P < .001) and 0 of the 13 subjects with sporadic CCM (P = .001). Adrenal calcifications in patients with fCCM were more frequently left sided, with 17 of 19 patients having more SFCs in the left adrenal gland than the right adrenal gland and 50 of the 61 observed SFCs (82%) found in the left adrenal gland. No subjects had SFCs on the right side only. In patients with fCCM, the presence of SFCs showed a positive correlation with age (P < .001) and number of brain lesions (P < .001). Conclusion Adrenal calcifications identified on CT scans are common in patients with fCCM and may be a clinically silent manifestation of disease. ^© RSNA, 2017.

Review of familial cerebral cavernous malformations and report of seven additional families

Cerebral cavernous malformations are vascular anomalies of the central nervous system characterized by clusters of enlarged, leaky capillaries. They are caused by loss-of-function mutations in KRIT1, CCM2, or PDCD10. The proteins encoded by these genes are involved in four partially interconnected signaling pathways that control angiogenesis and endothelial permeability. Cerebral cavernous malformations can occur sporadically, or as a familial autosomal dominant disorder (FCCM) with incomplete clinical and neuroradiological penetrance and great inter-individual variability. Although the clinical course is unpredictable, symptoms typically present during adult life and include headaches, focal neurological deficits, seizures, and potentially fatal stroke. In addition to neural lesions, extraneural cavernous malformations have been described in familial disease in several tissues, in particular the skin. We here present seven novel FCCM families with neurologic and cutaneous lesions. We review histopathological and clinical features and provide an update on the pathophysiology of cerebral cavernous malformations and associated cutaneous vascular lesions. © 2016 Wiley Periodicals, Inc.

CCM1 and the second life of proteins in adhesion complexes

It is well recognized that a number of proteins present within adhesion complexes perform discrete signaling functions outside these adhesion complexes, including transcriptional control. In this respect, β-catenin is a well-known example of an adhesion protein present both in cadherin complexes and in the nucleus where it regulates the TCF transcription factor. Here we discuss nuclear functions of adhesion complex proteins with a special focus on the CCM-1/KRIT-1 protein, which may turn out to be yet another adhesion complex protein with a second life.

Neurodermatology

Since the skin and the central and/or peripheral nervous system share a common source (the ectoderm), numerous genetic and acquired diseases (infectious, tumoral or autoimmune disorders) equally affect both. Neurologic diseases or symptoms such as stroke, cerebral or medullary vascular malformations, peripheral, brain or medullary tumors, epilepsy, ataxia, neurologic infections, or cognitive disorders (dementia, mental retardation) may be associated with specific cutaneous manifestations of which the discovery can facilitate the final diagnosis, thereby leading to specific treatment and/or genetic investigations. Careful examination of the skin, hair, and nails by the neurologist is consequently of the utmost importance; when unusual abnormalities of the skin are discovered or when greater expertise is required, consultation with a dermatologist is frequently advisable.

Cavernous malformations

Cavernous malformations (CMs) are vascular lesions found in the central nervous system (CNS) and throughout the body and have been called cavernomas, cavernous angiomas, and cavernous hemangiomas. This article discusses the epidemiology, natural history, diagnosis, treatment and follow-up of children who are found to harbor these lesions. CMs affect children by causing hemorrhage, seizure, focal neurologic deficits, and headache. Diagnosis is best made with magnetic resonance imaging. Patients with multiple lesions should be referred for genetic evaluation and counseling. Individuals with symptomatic, growing, or hemorrhagic malformations should be considered for surgical resection. Close follow-up after diagnosis and treatment is helpful to identify lesion progression or recurrence.

Pathogenesis of vascular anomalies

Vascular anomalies are localized defects of vascular development. Most of them occur sporadically (ie, there is no familial history of lesions, yet in a few cases clear inheritance is observed). These inherited forms are often characterized by multifocal lesions that are mainly small in size and increase in number with patients' age. The authors review the known (genetic) causes of vascular anomalies and call attention to the concept of Knudson's double-hit mechanism to explain incomplete penetrance and large clinical variation in expressivity observed in inherited vascular anomalies. The authors also discuss the identified pathophysiological pathways involved in vascular anomalies and how it has opened the doors toward a more refined classification of vascular anomalies and the development of animal models that can be tested for specific molecular therapies.

Venous malformation: update on aetiopathogenesis, diagnosis and management

The aim of this review was to discuss the current knowledge on aetiopathogenesis, diagnosis and therapeutic management of venous malformations (VMs). VMs are slow-flow vascular anomalies. They are simple, sporadic or familial (cutaneomucosal VMs or glomuvenous malformations), combined (e.g. capillaro-venous and capillaro-lymphaticovenous malformations) or syndromic (Klippel-Trenaunay, blue rubber bleb naevus and Maffucci). Genetic studies have identified causes of familial forms and of 40% of sporadic VMs. Another diagnostic advancement is the identification of elevated D-dimer level as the first biomarker of VMs within vascular anomalies. Those associated with pain are often responsive to low-molecular-weight heparin, which should also be used to avoid disseminated intravascular coagulopathy secondary to intervention, especially if fibrinogen level is low. Finally, development of a modified sclerosing agent, ethylcellulose-ethanol, has improved therapy. It is efficient and safe, and widens indications for sclerotherapy to sensitive and dangerous areas such as hands, feet and periocular area.