Proteus syndrome: an update

Alterations of the AKT Pathway in Sporadic Human Tumors, Inherited Susceptibility to Cancer, and Overgrowth Syndromes

The AKT kinases are critical signaling molecules that regulate cellular physiology upon the activation of tyrosine kinase receptors and phosphatidylinositol 3-kinases (PI3K). AKT kinases govern many cellular processes considered hallmarks of cancer, including cell proliferation and survival, cell size, tumor invasion, metastasis, and angiogenesis. AKT signaling is regulated by multiple tumor suppressors and oncogenic proteins whose loss or activation, respectively, leads to dysregulation of this pathway, thereby contributing to oncogenesis. Herein, we review the enormous body of literature documenting how the AKT pathway becomes hyperactivated in sporadic human tumors and various hereditary cancer syndromes. We also discuss the role of activating mutations of AKT pathway genes in various chimeric overgrowth disorders, including Proteus syndrome, hypoglycemia with hypertrophy, CLOVES and SOLAMEN syndromes, and hemimegalencephaly.

Proteus Syndrome: A Rare Congenital Disorder

An uncommon congenital hamartomatous disorder called Proteus syndrome is characterized by multifocal tissue expansion originating from all three germinal layers. Diagnosis mainly relies on clinical and radiological criteria. Here, we present a case of a 13-year-old female child exhibiting bony, soft tissue, and vascular abnormalities, along with developmental delay. We conclude by highlighting the importance of imaging studies in conjunction with physical examination, which are characterized by general and specific criteria to diagnose this rare condition until a specific gene test becomes available.

Human vascular organoids with a mosaic AKT1 mutation recapitulate Proteus syndrome

Vascular malformation, a key clinical phenotype of Proteus syndrome, lacks effective models for pathophysiological study and drug development due to limited patient sample access. To bridge this gap, we built a human vascular organoid model replicating Proteus syndrome's vasculature. Using CRISPR/Cas9 genome editing and gene overexpression, we created induced pluripotent stem cells (iPSCs) embodying the Proteus syndrome-specific AKTE17K point mutation for organoid generation. Our findings revealed that AKT overactivation in these organoids resulted in smaller sizes yet increased vascular connectivity, although with less stable connections. This could be due to the significant vasculogenesis induced by AKT overactivation. This phenomenon likely stems from boosted vasculogenesis triggered by AKT overactivation, leading to increased vascular sprouting. Additionally, a notable increase in dysfunctional PDGFRβ+ mural cells, impaired in matrix secretion, was observed in these AKT-overactivated organoids. The application of AKT inhibitors (ARQ092, AZD5363, or GDC0068) reversed the vascular malformations; the inhibitors' effectiveness was directly linked to reduced connectivity in the organoids. In summary, our study introduces an innovative in vitro model combining organoid technology and gene editing to explore vascular pathophysiology in Proteus syndrome. This model not only simulates Proteus syndrome vasculature but also holds potential for mimicking vasculatures of other genetically driven diseases. It represents an advance in drug development for rare diseases, historically plagued by slow progress.

Phenotypic Features of Cystic Lung Disease in Proteus Syndrome: A Clinical Trial

Rationale: Limited information is available regarding cystic lung disease in Proteus syndrome, a rare overgrowth disorder caused by a somatic activating variant in AKT1. Objectives: To define the phenotype of cystic lung disease in Proteus syndrome. Methods: Medical records, pulmonary function tests, and chest computed tomography of 39 individuals with Proteus syndrome evaluated at a single center were retrospectively reviewed. Lung histopathology from five affected individuals was examined. Results: Cystic lung disease affected 26 (67%) of 39 individuals. The mean age of affected individuals was 17.1 years. The lung cysts varied in size and location. Focal regions of heterogeneous lung parenchyma resembling emphysema were found in 81% of affected individuals. Mass effect was seen in 12% of affected individuals; pneumothorax occurred in one. Dyspnea and respiratory infections were reported by 38% and 35% of affected individuals, respectively. Abnormal pulmonary function and scoliosis were found in 96% of affected individuals. Lung disease progressed in seven of 10 affected individuals, and all five affected individuals younger than 20 years of age had progressive cystic lung disease. Three affected individuals had symptomatic improvement after lung resection. Histopathology showed cystic air space enlargement of varying severity. Conclusions: Cystic lung disease is common in Proteus syndrome and is likely to progress in affected individuals younger than 20 years of age. Screening asymptomatic individuals with Proteus syndrome for cystic lung disease is indicated. Surgical lung resection is a therapeutic option for affected individuals with severe disease. Clinical trial registered with www.clinicaltrials.gov (NCT00001403).

Proteus syndrome with sciatic nerve fibrolipomatous hamartoma: an uncommon finding in a rare disease: report of two cases with literature review

Proteus syndrome is an extremely rare condition, characterized by progressive asymmetric overgrowth of multiple body tissues. Here, we present two cases of Proteus syndrome demonstrating typical clinical and radiological features of Proteus syndrome, in addition to an uncommon fibrolipomatous hamartoma of the sciatic nerve. The first case is a 5-year-old girl who presented with seizures. The patient showed facial dysmorphic features, left head enlargement, kyphoscoliosis, asymmetric overgrowth of the right lower limb, right foot drop, and cribriform connective tissue nevi on the right palm and the right sole. Radiological examinations demonstrated left calvarial hyperostosis, dysplasia of the left cerebral hemisphere, dysregulation of the subcutaneous adipose fat of the body, kyphoscoliosis, and lipoma of the filum terminale. CT of both thighs showed asymmetric soft tissue overgrowth of the right thigh, associated with diffuse enlargement and fatty infiltration of the right sciatic nerve starting from the upper thigh, down to its bifurcation into the tibial and common peroneal nerves. The second case is an 18-year-old girl who presented with left conductive deafness. The patient showed facial dysmorphic features, right head enlargement, asymmetric overgrowth of the right upper limb, kyphoscoliosis, left foot drop, and cribriform connective tissue nevi on the nose and the left foot. Radiological examinations demonstrated right calvarial hyperostosis, left external auditory canal hyperostosis and stenosis, and kyphoscoliosis. CT and MRI of both thighs showed diffuse enlargement of the left sciatic nerve starting from the upper thigh down to the mid-thigh and showing interfascicular adipose tissue proliferation, giving the typical features of nerve lipomatosis.

Proteus syndrome in pregnancy: A case report

Proteus syndrome is a rare, multi-system, genetic syndrome characterised by atypical and excessive growth of skeletal tissue. Clinical presentations include abnormal musculoskeletal growth and cutaneous lesions. Due to its rarity, there have been a limited number of published case reports of Proteus syndrome. This is the first case report on the management of Proteus syndrome in pregnancy. We present the case of a pregnant woman with Proteus syndrome in her first pregnancy in a large teaching hospital and discuss the considerations and challenges faced in her antenatal, intrapartum and postnatal care.

Clinical Phenotype and Bone Biopsy Characteristics in a Child with Proteus Syndrome

Proteus syndrome is a rare genetic disorder, which is characterized by progressive, segmental, or patchy overgrowth of diverse tissues of all germ layers, including the skeleton. Here, we present a 9-year-old girl with a somatic-activating mutation (c.49G > A; p.Glu17Lys) in AKT1 gene in a mosaic status typical for Proteus syndrome. She presented with hemihypertrophy of the right lower limb and a "moccasin" lesion among others. A transiliac bone biopsy was analyzed for bone histology/histomorphometry as well as bone mineralization density distribution (BMDD) and osteocyte lacunae sections (OLS) characteristics based on quantitative backscattered electron imaging. Bone histomorphometry revealed highly increased mineralizing surface (Z-score + 2.3) and mineral apposition rate (Z-score + 19.3), no osteoclasts (Z-score - 2.1), and an increased amount of primary bone in the external cortex. BMDD abnormalities included a decreased mode calcium concentration in cancellous bone (Z-score - 1.7) and an increased percentage of highly mineralized cortical bone area (Z-score + 2.4) compared to reference. OLS characteristics showed several differences compared to reference data; among them, there were the highly increased OLS-porosity, OLS-area, and OLS-perimeter on the external cortex (Z-scores + 6.8, + 4.4 and 5.4, respectively). Our findings suggest that increased bone formation reduced matrix mineralization in cancellous bone while the enhanced amount of primary bone in the external cortex increased the portion of highly mineralized cortical bone and caused OLS-characteristics abnormalities. Our results indicate further that remodeling of primary bone might be disturbed or delayed in agreement with the decreased number of osteoclasts observed in this child with Proteus syndrome.

Phenotype and Surgical Treatment in a Case of Proteus Syndrome With Craniofacial and Oral Findings

BACKGROUND/AIM

Proteus syndrome is a sporadic disease that is particularly noticeable due to the disproportional growth of body segments. The disease is a genetic mosaic. The mutations can arise from any of the germ layers, an explanation of the very variable phenotype. The aim of this report is to communicate the diagnosis and management of an unusual case of Proteus Syndrome with special attention to oral and craniofacial findings.

CASE REPORT

A 15-year-old patient was referred for surgical treatment of pronounced skull malformations and correction of oral mucosal hyperplasia. Treatment caused significant improvement in facial appearance and oral soft tissue conditions.

CONCLUSION

Surgical measures adapted to the local findings and symptoms can often relieve severe disfigurement of the patient.

Proteus Syndrome: A Rare Case in An Adult Ward

Proteus syndrome is an extremely rare disorder that manifests as an asymmetric, disproportionate overgrowth of any connective tissue, such as bone, fat or epidermal nevi, in a mosaic or patchy pattern. It has an estimated prevalence of less than 1/1,000,000 live births. The diagnosis can be difficult because the phenotypes of the patients are variable. Many individuals develop cutaneous capillary malformation and prominent varicosities (large and complex vascular malformations). Thus, Proteus syndrome patients are at risk of developing deep vein thrombosis and pulmonary embolism. The authors present the case of a patient with Proteus syndrome who was admitted because of pulmonary thromboembolism and presented hypertrophy of the left arm and left hemithorax.

LEARNING POINTS

Proteus syndrome is an extremely rare disorder that manifests as an asymmetric, disproportionate overgrowth of any connective tissue.The diagnosis can be difficult because the phenotypes are variable.It is important to keep in mind the importance of anticoagulation because patients are at risk of developing deep vein thrombosis and pulmonary embolism.

Diagnostic Approach to Macrocephaly in Children

Macrocephaly affects up to 5% of the pediatric population and is defined as an abnormally large head with an occipitofrontal circumference (OFC) >2 standard deviations (SD) above the mean for a given age and sex. Taking into account that about 2-3% of the healthy population has an OFC between 2 and 3 SD, macrocephaly is considered as "clinically relevant" when OFC is above 3 SD. This implies the urgent need for a diagnostic workflow to use in the clinical setting to dissect the several causes of increased OFC, from the benign form of familial macrocephaly and the Benign enlargement of subarachnoid spaces (BESS) to many pathological conditions, including genetic disorders. Moreover, macrocephaly should be differentiated by megalencephaly (MEG), which refers exclusively to brain overgrowth, exceeding twice the SD (3SD-"clinically relevant" megalencephaly). While macrocephaly can be isolated and benign or may be the first indication of an underlying congenital, genetic, or acquired disorder, megalencephaly is most likely due to a genetic cause. Apart from the head size evaluation, a detailed family and personal history, neuroimaging, and a careful clinical evaluation are crucial to reach the correct diagnosis. In this review, we seek to underline the clinical aspects of macrocephaly and megalencephaly, emphasizing the main differential diagnosis with a major focus on common genetic disorders. We thus provide a clinico-radiological algorithm to guide pediatricians in the assessment of children with macrocephaly.

Normal Ranges of Upper Extremity Length, Circumference, and Rate of Growth in the Pediatric Population

Background: Upper extremity length and circumference abnormalities are present in a number of conditions in the pediatric population. In most cases, upper limb hypoplasia and hypertrophy are diagnosed when one limb appears substantially different from the other during physical examination. However, occasionally when this discrepancy exists, it can be difficult to determine which limb is the abnormal one. The purpose of this study was to establish normal values for upper extremity length, circumference, and rate of growth in children aged 0 to 17 years. Methods: In all, 377 participants had 4 measurements taken of each upper extremity: upper arm length, upper arm circumference, forearm length, and forearm circumference. Statistical analysis was performed to identify differences and rates of growth. Results: Mean values for arm and forearm length and circumference for each age, 0 to 17 years, were established. The determination of a child's expected arm length is dependent on his or her height, age, and sex, while the calculation of a child's expected forearm length depends on his or her weight, age, and sex. Male and female arms and forearms have similar growth rates of lengths and circumferences. No significant differences were found between right and left extremities for each of the 4 measurements taken. Conclusions: Contralateral limbs can be used for comparison of length and circumference of the arm and forearm in cases of unilateral upper extremity abnormality. The establishment of normal values for upper extremity length, circumference, and growth rate will be a useful diagnostic tool for upper extremity hypoplasia and hypertrophy.

Proteus syndrome of the foot: A case report and literature review

Proteus syndrome (PS) is an extremely rare and sporadic disorder characterized by asymmetric and/or disproportionate overgrowth of limbs, hamartomas, and vascular malformations. The onset of overgrowth usually involves the skin, bone, fat, and other connective tissues in a patchy or mosaic pattern. Partial gigantism of the affected limb or digit is a pathognomonic sign of PS. Thus far, only a few cases of PS have been recorded in the literature. In the present report, a case of PS in a 35-year old woman with classic cerebriform plantar hyperplasia and macrodactyly of the left foot was documented. The clinical and molecular characteristics and differential diagnosis of PS are also discussed in this report.

Clinical report: one year of treatment of Proteus syndrome with miransertib (ARQ 092)

A 20-yr-old man with Proteus syndrome (PS) and somatic mosaicism of the AKT1 c.49G > A p.(E17K) variant had asymmetric overgrowth of the right frontal and facial bones, asymmetric spinal overgrowth with thoracolumbar scoliosis, dilatation of the inferior vena cava, testicular cystadenoma, bilateral knee deformities, macrodactyly, and apparent intellectual disability. Miransertib (ARQ 092) is an oral, allosteric, selective pan-AKT inhibitor initially developed for cancer therapeutics, now being evaluated for the treatment of PS. After baseline evaluation, the patient started unblinded treatment of 10 mg oral miransertib daily (∼5 mg/m²/day), escalated to 30 mg daily (∼15 mg/m²/day), and then to 50 mg daily (∼25 mg/m²/day) after 3 mo of treatment. Adverse events included dry mouth, one episode of gingivostomatitis, and loose, painful dentition due to preexisting periodontal disease, all of which resolved spontaneously. After 11 mo of treatment, the patient reported improved general well-being, increased mobility of the ankle, spine, and hands, a subjective decrease in size of the right facial bone overgrowth, and reduced areas of cerebriform connective tissue nevi on the soles. Whole-body MRI findings were stable without apparent disease progression. We conclude that 1 yr of treatment with miransertib was beneficial in this case.

Characterization and Childhood Tumor Risk Assessment of Genetic and Epigenetic Syndromes Associated With Lateralized Overgrowth

Lateralized overgrowth (LO), or segmental overgrowth, is defined as an increase in growth of tissue (bone, muscle, connective tissue, vasculature, etc.) in any region of the body. Some overgrowth syndromes, characterized by both generalized and lateralized overgrowth, have been associated with an increased risk of tumor development. This may be due to the underlying genetic and epigenetic defects that lead to disrupted cell growth and proliferation pathways resulting in the overgrowth and tumor phenotypes. This chapter focuses on the four most common syndromes characterized by LO: Beckwith-Wiedemann spectrum (BWSp), PIK3CA-related overgrowth spectrum (PROS), Proteus syndrome (PS), and PTEN hamartoma tumor syndrome (PHTS). These syndromes demonstrate variable risks for tumor development in patients affected by LO, and we provide a comprehensive literature review of all common tumors reported in patients diagnosed with an LO-related disorder. This review summarizes the current data on tumor risk among these disorders and their associated tumor screening guidelines. Furthermore, this chapter highlights the importance of an accurate diagnosis when a patient presents with LO as similar phenotypes are associated with different tumor risks, thereby altering preventative screening protocols.

Maxillofacial manifestations of Proteus syndrome: a systematic review with a case report

OBJECTIVES

Proteus syndrome (PS) is an extremely rare disorder with asymmetric and disproportionate bone overgrowth. Craniofacial abnormalities in PS are less frequent than skeletal abnormalities. Although there are recognized oral and maxillofacial manifestations of PS, few case reports describing these manifestations are available. Thus, the objective of this systematic review and case report is to describe oral and maxillofacial manifestations of PS and to report a PS case.

METHODS

A 31-year-old male presented with restricted mouth opening and pain during mastication. A panoramic radiograph and an occlusal radiograph were obtained. Reports with relevant keywords were assessed. Data were summarized and demonstrated using a critical appraisal checklist for case reports.

RESULTS

The panoramic radiograph demonstrated unilateral overgrowth of the mandible, impacted teeth, and deciduous prolonged retention. Thirteen PS case reports were identified.

CONCLUSIONS

Proteus syndrome oral and maxillofacial manifestations may include dental agenesis, impacted teeth, malocclusion, asymmetric dental growth and maturation, frontal line displacement, asymmetric tongue enlargement, mandibular hemihypertrophy and asymmetry, presence of exostoses/hyperostosis, degenerative changes in the temporomandibular joint, alterations of maxillary and mandibular vertical and/or horizontal growth, and enlargement of mandibular canal and foramen. The PROSPERO systematic review registration number is CRD42019140942.

Thrombosis risk factors in PIK3CA-related overgrowth spectrum and Proteus syndrome

Increased risk of thromboembolism has been recognized in individuals with mosaic overgrowth disorders, Proteus syndrome (PS) and PIK3CA-related overgrowth spectrum (PROS), including Klippel-Trenaunay syndrome and CLOVES syndrome. PS and PROS have distinct, yet overlapping clinical findings and are caused by somatic pathogenic variants in the PI3K/AKT gene signaling pathway. PS is caused by a single somatic activating AKT1 c.49G > A p.E17K variant while PROS can be caused one of multiple variants in PIK3CA. The role of prothrombotic factors, endothelial cell adhesion molecules, and vascular malformations in both PS and PROS have not been previously investigated. A pilot study of prospective clinical and laboratory evaluations with the purposes of identifying potential risk factors for thrombosis was conducted. Doppler ultrasounds and magnetic resonance angiogram/ venography (MRA/MRV) scans identified vascular malformations in PS and PROS that were not appreciated on physical examination. Abnormal D-dimers (0.60-2.0 mcg/ml) occurred in half of individuals, many having vascular malformations, but no thromboses. Soluble vascular endothelial markers, including thrombomodulin, soluble vascular adhesion molecule (sVCAM), soluble intercellular adhesion molecule (sICAM), E-selectin, and P-selectin were significantly higher in PS and PROS compared to controls. However, no single attribute was identified that explained the risk of thrombosis. Predisposition to thrombosis is likely multifactorial with risk factors including chronic stasis within vascular malformations, stasis from impaired mobility (e.g., following surgery), decreased anticoagulant proteins, and effects of AKT1 and PIK3CA variants on vascular endothelium. Based on our findings, we propose clinical recommendations for surveillance of thrombosis in PS and PROS.

Tumor risk and surveillance for children with hereditary disorders affecting growth

PURPOSE OF REVIEW

Hereditary disorders affecting growth (both overgrowth and growth retardation) are frequently associated with heightened risk of neoplastic disease. This review summarizes the tumor spectra associated with these conditions and identifies disease-specific screening approaches.

RECENT FINDINGS

An understanding of the molecular events underlying many of these growth disorders has evolved significantly over the past several years. Recognition of genotype-phenotype associations, in many cases, informs the cancer risk profile. Additionally, accumulating data suggest a benefit of rational presymptomatic surveillance for at-risk individuals, with a reduction in tumor-associated morbidity. Recent clinical practice recommendations have established risk-driven paradigms for tumor surveillance in the context of hereditary tumor predisposition syndromes, including those affecting growth.

SUMMARY

Clinicians caring for children with growth disorders should be aware of syndromic associations and the associated cancer risks. Knowledge of tumor spectra and recommended surveillance strategies may facilitate tumor diagnosis at an early stage and reduce morbidity of the disease and associated treatments.

Schimmelpenning Syndrome: An Association with Vascular Anomalies

Objective:

Schimmelpenning syndrome is a rare neurocutaneous disorder characterized by craniofacial nevus sebaceus in association with seizures, developmental delay, and ocular or skeletal pathology. Vascular anomalies also have been described in this condition, and some authors have suggested that the two entities are associated. The purpose of this study was to determine the prevalence of vascular anomalies in Schimmelpenning syndrome.

Methods:

We reviewed the medical records of patients with Schimmelpenning syndrome who were evaluated or were managed at Children's Hospital Boston between 1980 and 2005. In addition, all published cases purported to be Schimmelpenning syndrome were analyzed to determine whether the primary diagnosis was accurate and whether or not there were concurrent vascular anomalies.

Results:

Three of nine patients (33.3%) in our series had a vascular malformation. One patient had coarctation, aortic aneurysm, renal artery, and carotid stenosis; another had a thoracic lymphatic anomaly with chylothorax; and the third had lymphedema of the lower extremities and lymphatic malformation of the neck/chest with chylothorax. Additional findings were seizures (78%), ocular pathology (78%), developmental delay (56%), and skeletal abnormalities (67%). Of 119 cases of authenticated Schimmelpenning syndrome in the literature, 18 vascular malformations were documented in 15 patients (12.6%): venous (n = 7); arterial (n = 5); lymphatic (n = 3); capillary (n = 2); and arteriovenous (n = 1).

Conclusions:

Vascular malformations occur with a higher frequency (12.6 to 33%) in patients with Schimmelpenning syndrome compared with the general population (<1%). Therefore, we conclude that there is an association between vascular anomalies and Schimmelpenning syndrome.

Venous Thromboembolism in Pediatric Vascular Anomalies

The presence of a vascular anomaly suggests that capillaries, veins, arteries, and/or lymphatic vessels have demonstrated abnormal development and growth. Often dilated and misshaped, these vessels augment normal flow of blood and lymphatic fluids that increases the overall risk to develop intralesional thrombosis. Abnormal endothelial and lymphoendothelial cells activate hemostasis and hyperfibrinolytic pathways through poorly understood mechanisms, which contribute to the development of localized intravascular coagulopathy. Vascular malformations, tumors, and complex combined syndromes demonstrate varying degrees of prothrombotic activity and consumptive coagulopathy depending on the vessels involved and the pattern and extent of abnormal growth. The clinical impact of venous thromboembolism in pediatric vascular anomalies varies from painful syndromes that disrupt quality of life to life-threatening embolic disease. There remains little literature on the study, evaluation, and treatment of thrombosis in pediatric vascular anomalies. However, there have been great advances in our ability to image complex lesions, to surgically and interventionally augment disease, and to provide enhanced supportive care including patient education, compression therapy, and strategic use of anticoagulation.

A rare case of dysembryoplastic neuroepithelial tumor combined with encephalocraniocutaneous lipomatosis and intractable seizures

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous syndrome that affects ectomesodermal tissues (skin, eyes, adipose tissue, and brain). The neurologic manifestations associated with ECCL are various including seizures. However, ECCL patients very rarely develop brain tumors that originate from the neuroepithelium. This is the first described case of ECCL in combination with dysembryoplastic neuroepithelial tumor (DNET) that presented with intractable seizures. A 7-year-old girl was admitted to our center because of ECCL and associated uncontrolled seizures. She was born with right anophthalmia and lipomatosis in the right temporal area and endured right temporal lipoma excision at 3 years of age. Seizures began when she was 3 years old, but did not respond to multiple antiepileptic drugs. Brain magnetic resonance (MR) imaging performed at 8 and 10 years of age revealed an interval increase of multifocal hyperintense lesions in the basal ganglia, thalamus, cerebellum, periventricular white matter, and, especially, the right temporal area. A nodular mass near the right hippocampus demonstrated the absence of N-acetylaspartate decrease on brain MR spectroscopy and mildly increased methionine uptake on brain positron emission tomography, suggesting low-grade tumor. Twenty-four-hour video electroencephalographic monitoring also indicated seizures originating from the right temporal area. Right temporal lobectomy was performed without complications, and the nodular lesion was pathologically identified as DNET. The patient has been seizure-free for 14 months since surgery. Although ECCL-associated brain tumors are very rare, careful follow-up imaging and surgical resection is recommended for patients with intractable seizures.

Tip of an Iceberg: Skull Fracture as an Adult Presentation of Encephalocraniocutaneous Lipomatosis

The severity of seizures presenting to the emergency department ranges from benign to life threatening. There are also a wide number of possible etiologies. Computed tomography (CT) emergency imaging may be required at presentation to elucidate a possible cause and assess signs of intracranial trauma. This case describes a serious seizure episode in a young man while on holiday. A CT brain showed a skull fracture as a consequence of seizure-related head trauma but unexpectedly there were image findings consistent with encephalocraniocutaneous lipomatosis. The important radiological features of encephalocraniocutaneous lipomatosis and a differential diagnosis are presented.

Unilateral hypertrophic skin lesions, hemimegalencephaly, and meningioma: The many faces of Proteus syndrome

Proteus syndrome is a rare condition with a wide spectrum of abnormalities. It is characterized by hamartomatous malformations involving multiple organs. Serious complications may ensue, such as pulmonary embolism, cystic lung disease, and various neoplasms such as parotid adenomas, ovarian cystadenomas, and meningiomas. We report here a case of Proteus syndrome in a 21-year-old woman who had facial hemihypertrophy, cerebriform plantar hyperplasia, hemimegalencephaly, and meningioma for the rarity of the entity.

Epidemiological and genetic clues for molecular mechanisms involved in uterine leiomyoma development and growth

BACKGROUND

Uterine leiomyomas (fibroids) are highly prevalent benign smooth muscle tumors of the uterus. In the USA, the lifetime risk for women developing uterine leiomyomas is estimated as up to 75%. Except for hysterectomy, most therapies or treatments often provide only partial or temporary relief and are not successful in every patient. There is a clear racial disparity in the disease; African-American women are estimated to be three times more likely to develop uterine leiomyomas and generally develop more severe symptoms. There is also familial clustering between first-degree relatives and twins, and multiple inherited syndromes in which fibroid development occurs. Leiomyomas have been described as clonal and hormonally regulated, but despite the healthcare burden imposed by the disease, the etiology of uterine leiomyomas remains largely unknown. The mechanisms involved in their growth are also essentially unknown, which has contributed to the slow progress in development of effective treatment options.

METHODS

A comprehensive PubMed search for and critical assessment of articles related to the epidemiological, biological and genetic clues for uterine leiomyoma development was performed. The individual functions of some of the best candidate genes are explained to provide more insight into their biological function and to interconnect and organize genes and pathways in one overarching figure that represents the current state of knowledge about uterine leiomyoma development and growth.

RESULTS

In this review, the widely recognized roles of estrogen and progesterone in uterine leiomyoma pathobiology on the basis of clinical and experimental data are presented. This is followed by fundamental aspects and concepts including the possible cellular origin of uterine fibroids. The central themes in the subsequent parts are cytogenetic aberrations in leiomyomas and the racial/ethnic disparities in uterine fibroid biology. Then, the attributes of various in vitro and in vivo, human syndrome, rodent xenograft, naturally mutant, and genetically modified models used to study possible molecular mechanisms of leiomyoma development and growth are described. Particular emphasis is placed on known links to fibrosis, hypertrophy, and hyperplasia and genes that are potentially important in these processes.

CONCLUSIONS

Menstrual cycle-related injury and repair and coinciding hormonal cycling appears to affect myometrial stem cells that, at a certain stage of fibroid development, often obtain cytogenetic aberrations and mutations of Mediator complex subunit 12 (MED12). Mammalian target of rapamycin (mTOR), a master regulator of proliferation, is activated in many of these tumors, possibly by mechanisms that are similar to some human fibrosis syndromes and/or by mutation of upstream tumor suppressor genes. Animal models of the disease support some of these dysregulated pathways in fibroid etiology or pathogenesis, but none are definitive. All of this suggests that there are likely several key mechanisms involved in the disease that, in addition to increasing the complexity of uterine fibroid pathobiology, offer possible approaches for patient-specific therapies. A final model that incorporates many of these reported mechanisms is presented with a discussion of their implications for leiomyoma clinical practice.

Proteus syndrome: Report of a case with AKT1 mutation in a dental cyst

Proteus syndrome (PS) is a sporadic and rare congenital disorder characterized by a patchy or mosaic postnatal overgrowth, sometimes involving the face. The onset of overgrowth typically occurs in infancy and can commonly involve skin, connective tissue, central nervous system, eyes and viscera. The progressive overgrowth causes severe complications, such as skeletal deformities, cystic lung disease, invasive lipomas, connective tissue hyperplasia, benign and malignant tumours and deep venous thrombosis with pulmonary embolism, which can cause premature death. This disorder is caused by somatic mosaicism for a specific activating AKT1 mutation that would be lethal in a non-mosaic state. In this report, current knowledge of the aetiology, the diagnosis and the craniofacial manifestations of the disorder are reviewed. The short-term management of a 7-year-old patient with unusual oral manifestations is described. For the first time mutation of AKT1 (c.49G > A) gene was detected both in cranial exostosis and in central odontogenic fibroma of the lower jaw.

Familial multiple lipomas coexisting with celiac disease: a case report

Introduction

Gluten enteropathy (celiac disease) is a chronic disease and presents as diarrhea, weight loss and anemia.

Case presentation

A 35-year-old Caucasian man with gluten enteropathy, familial multiple lipomas and seborrheic keratosis was seen in our clinic. After confirmation of the diagnosis, he was advised to follow a gluten-free diet. His clinical improvement was evaluated and confirmed with biopsy.

Conclusion

Celiac disease is known to be associated with many systemic diseases and skin lesions but its association with familial multiple lipomas has not yet been reported.

Operative management of splenic injury in a patient with proteus syndrome

A 20-year-old female with Proteus syndrome sustained splenic injury after fall from a bike. She was initially managed non-operatively at a different hospital for three days and was then referred to our level I trauma center in view of increasing abdominal pain and distention. On admission in the Emergency Department (ED), her pulse rate was 120 per minute and blood pressure was 108/68 mm Hg. Clinical examination showed a distended abdomen with left hypochondrial pain. Ultrasonogram (USG) and Computed Tomography (CT) of the abdomen showed splenomegaly and grade III splenic injury with significant hemoperitoneum. Her hemoglobin was 2.9 g/dl with packed cell volume (PCV) of 12%. In view of low hemoglobin and possibility of pathologic spleen, splenectomy was done. Microscopic examination of the spleen showed hemangiolymphangioma. The patient was discharged on the 5^th post-operative day and is doing well at 6 months of follow-up.

Soft-tissue necrosis complicating tibial osteotomy in a child with Proteus syndrome

INTRODUCTION

Proteus syndrome is a rare congenital hamartomatous disease frequently responsible for musculoskeletal deformities. The results and complications of surgical treatment are not well documented owing to the scarcity of reported cases.

CASE REPORT

The authors report a case of poor evolution of valgus proximal tibial osteotomy in a 6-year-old girl with Proteus syndrome. The surgery was complicated by extensive deep wound necrosis exposing the tibial bone, necessitating surgical excision, antibiotherapy and controlled wound healing. At 1 year postoperatively, the deformity recurred.

DISCUSSION

The possibility of serious wound complications and of recurrence must be kept in mind when operating on a limb deformity in patients with Proteus syndrome. Potential complications should be taken into account in selecting the surgical correction technique: epiphysiodesis may be preferable to osteotomy.

Radiographic findings of Proteus Syndrome

The extremely rare Proteus Syndrome is a hamartomatous congenital syndrome with substantial variability between clinical patient presentations. The diagnostic criteria consist of a multitude of clinical findings including hemihypertrophy, macrodactyly, epidermal nevi, subcutaneous hamartomatous tumors, and bony abnormalities. These clinical findings correlate with striking radiographic findings.

Low-level mesodermal somatic mutation mosaicism: late-onset craniofacial and cervical spinal hyperostoses

Craniofacial and cervical spinal hyperostoses are rarely seen in the absence of other abnormalities. Only seven patients with isolated cranial hyperostoses have been reported, and only a single patient with both calvarial and cervical vertebral hyperostoses. We report on an adult with late-onset right-sided asymmetrical hyperostoses of the cranium, mandible, and cervical vertebrae in the absence of an AKT1 mutation. At presentation, the patient displayed neither generalized overgrowth nor dysregulated adipose tissue. Standard polymerase chain reaction and Sanger sequencing of DNA extracted from formalin-fixed paraffin-embedded frontal bone and mandibular angular bone was negative for an AKT1 mutation. Though the patient's clinical manifestations did not fulfill the consensus diagnostic criteria of Proteus syndrome, the mosaic distribution of lesions, the sporadic occurrence, and the patient's progressive course were consistent with a somatic mosaicism similar to that syndrome. Hence, the patient's phenotype may have been caused by a very late mesodermal somatic mutation during embryogenesis.

Lymphatic vessel abnormalities arising from disorders of Ras signal transduction

A number of genetic diseases in man have been described in which abnormalities in the development and function of the lymphatic vascular (LV) system are prominent features. The genes that are mutated in these diseases are varied and include genes that encode lymphatic endothelial cell (LEC) growth factor receptors and their ligands and transcription factors that control LEC fate and function. In addition, an increasing number of genes have been identified that encode components of the Ras signal transduction pathway that conveys signals from cell surface receptors to regulate cell growth, proliferation, and differentiation. Gene targeting studies performed in mice have confirmed that the LV system is particularly susceptible to perturbations in the Ras pathway.

Proteus syndrome: Clinical diagnosis of a series of cases

OBJECTIVES

This paper describes the clinical diagnosis of Proteus syndrome (PS) in children referred for evaluation of asymmetric disproportionate overgrowth.

MATERIALS AND METHODS

Retrospective, descriptive, cross-sectional study conducted from January 1998 to December 2010.

RESULTS

During the study period, 2011 new patients were evaluated. Thirteen (0.65%) patients presented features suggestive of PS. These patients were formally evaluated based on the revised diagnostic criteria proposed by Biesecker. The mean age was 6.92 ± 5.1 years. Ten patients (76.9%) were females. All subjects had asymmetric disproportionate overgrowth. Other dysmorphic features were as follows: macrodactily (84.6%); linear epidermal nevus (41.6%); hemangioma (30.7%); and lipoma (23%). Six patients fulfilled the diagnostic criteria for PS.

CONCLUSIONS

The diagnostic rate of only 46.1% of patients with PS confirms the diagnostic difficulties and the need for continuous monitoring and periodic review of these patients since the clinical manifestations of this syndrome become more evident with aging. Molecular tests may help the differential diagnosis of Proteus syndrome when they became commercially available.

Proteus syndrome review: molecular, clinical, and pathologic features

Proteus syndrome is caused by an activating AKT1 mutation (c.49G>A, p.Glu17Lys). Many variable features are possible in this mosaic disorder, including: (i) disproportionate, asymmetric, and distorting overgrowth; (ii) bone abnormalities different from those observed in other disorders; (iii) a characteristic cerebriform connective tissue nevus made up of highly collagenized connective tissue; (iv) epidermal nevi in early life, consisting of acanthosis and hyperkeratosis; (v) vascular malformations of the capillary, venous, or lymphatic types; (vi) dysregulated adipose tissue including lipomas, lipohypoplasia, fatty overgrowth, and localized fat deposits; (vii) other unusual features, including bullous lung alterations; specific neoplasms; a facial phenotype associated with intellectual disability and/or seizures, and/or brain malformations; and (viii) deep vein thrombosis, resulting in premature death. Concluding remarks address diagnostic criteria, natural history, management, psychosocial issues, and differential diagnosis.

Proteus syndrome: Clinical profile of six patients and review of literature

OBJECTIVE:

Proteus syndrome (PS) is characterized by patchy or segmental overgrowth and hyperplasia of multiple tissues and organs, along with susceptibility to development of tumors. Very few cases are reported in literature from developing countries. Due to certain overlapping features with other overgrowth syndromes, diagnosis is usually delayed. Our aim was to describe clinical profile of this rare condition in six patients.

MATERIALS AND METHODS:

Retrospective case sheet review of patients followed in a Pediatric Genetic and Metabolic clinic at a tertiary care institute of North India with a diagnosis of hemihypertrophy/overgrowth syndrome.

RESULTS:

Six cases presented with asymmetric overgrowth and peculiar features suggestive of PS were included in this study. Age at presentation was 2 months to 10 years; two were males and four were females. Hemihypertrophy was noticed in only one case at birth, and focal overgrowths in rest of other patients were seen later during childhood.

CONCLUSION:

Due to certain overlapping features with other overgrowth syndromes, diagnosis of PS is usually delayed. Pediatricians are the first persons who come across such patients and they should be aware about this rare condition.

Diverse mechanisms of AKT pathway activation in human malignancy

AKT/PKB (Protein Kinase B) are central proteins mediating signals from receptor tyrosine kinases and phosphatidylinositol 3-kinase. AKT kinases are involved in a number of important cellular processes including cell proliferation and survival, cell size in response to nutrient availability, tumor invasion/metastasis, and angiogenesis.Various components of the AKT signaling pathway are encoded by tumor suppressor genes and oncogenes whose loss or activation, respectively, plays an important role in tumorigenesis. The growing body of evidence connecting deregulated AKT signaling with sporadic human cancers and inherited cancer predisposition syndromes is discussed. We also highlight new findings regarding the involvement of activating mutations of AKT1, AKT2, and AKT3 in somatic overgrowth disorders: Proteus syndrome, hypoglycemia with hypertrophy, and hemimegalencephaly, respectively. In addition, we review recent literature documenting the various ways the AKT signaling pathway is activated in human cancers and consequences for molecularly targeted therapies.

Genodermatoses caused by genetic mosaicism

Genetic mosaicism is defined as the existence of at least two genetically distinct cell populations within one individual. Mosaic presentation of genetic disorders is common and is often particularly obvious in the skin, because there it will generate recognizable patterns. Recognizing those can frequently assist in establishing a diagnosis. In this review, we discuss the mechanisms that give rise to genetic mosaicism. We describe its most frequent cutaneous manifestations that are relevant to paediatric practice. While most mosaic genetic diseases are rare, it is important to recognize them so that patients and parents may receive appropriate genetic counselling. Moreover, recent developments are now resulting in novel, targeted treatments for such disorders that promise to considerably improve patients' lives.

Single lobe disease in cases of advanced endemic goiter: a new phenotype

OBJECTIVES

To report a new phenotype of advanced endemic goiter that affects only one lobe of the thyroid gland.

PATIENTS AND METHODS

This study included 60 patients from the west of Sudan with long-standing unilateral simple endemic goiter that required obectomy, with emphasis on the gross appearance, measurements and cytological features of the contralateral lobe.

RESULTS

Out of 60 patients with unilateral goiter, 50 (83%) were found to have the disease on the ipsilateral lobe only (monolobar goiter). The contralateral lobe in these 50 patients showed no nodularity, and its volume was within the normal limits. All patients with monolobar disease had total lobectomy on the affected side, and postoperatively they continued to have normal blood levels of T3, T4 and TSH.

CONCLUSION

We report a new phenotype of advanced endemic goiter that affects only one lobe of the thyroid gland, and in the presence of a structurally and functionally normal contralateral lobe.

A severe and rapidly progressive case of proteus syndrome in a neonate who presented with unilateral hydrocephalus apart from other typical features of the proteus syndrome

Proteus syndrome is a rare hamartomatous disorder affecting multiple tissues and manifesting itself in a variety of ways. The understanding of the complete spectrum of clinical features, the natural clinical course of the disease and the proper management of such a rare but highly variable syndrome depend heavily on experiences gathered by previously reported cases. We present an unusually severely affected and rapidly progressive case of proteus syndrome in a neonate who presented with craniofacial hemihypertrophy, subcutaneous masses, capillary hemangioma, varicose veins, epidermal nevi and macrodactyly. The cranial ultrasonogram revealed unilateral hydrocephalus with partial obstruction of the foramen of monro.

Connective tissue nevi in children: institutional experience and review

BACKGROUND

Connective tissue nevi (CTN) are circumscribed hamartomas of the skin in which there is an abnormal mixture of normal components of the dermis that may be sporadic or associated with syndromes such as Buschke-Ollendorff, tuberous sclerosis, and Proteus.

OBJECTIVE

We sought to specify the clinical and histologic features of CTN in childhood and to propose a diagnostic approach and updated classification.

METHODS

This was a retrospective study in a tertiary pediatric outpatient population, accessing clinical and histopathological records.

RESULTS

We classified 114 cases of CTN from 1980 to 2008.

LIMITATIONS

The majority of cases were confirmed by histopathological examination. Therefore, our series excludes many CTN that were not biopsied. In addition, follow-up was variable.

CONCLUSION

Our series demonstrates the usefulness of a modified classification for CTN. Biopsy should be done when clinical diagnosis is uncertain, or in multiple lesions. When biopsy is performed it should include normal-appearing skin for comparison and, in Buschke-Ollendorff syndrome, limited anterior-posterior x-rays of the hands, wrists, feet, ankles, knees, and pelvis instead of a full skeletal survey.