Survival patterns of childhood neuroblastoma: an analysis of clinical data from Southern-Eastern European countries.

The prognosis of children with neuroblastoma (NBL) can be dismal with significant variations depending on the stage and biology of the tumor. We assessed the event-free (EFS) and overall (OS) survival using harmonized data from three Southern-Eastern European (SEE) countries. Data for 520 incident NBL cases (2009-2018) were collected from Greece, Slovenia and Russia. Kaplan-Meier curves were fitted, and EFS/OS were derived from Cox proportional models by study variables including the protocol-based risk-group (low/observation, intermediate, high). Over one-third of cases were coded in the high-risk group, of which 23 children (4.4%) received treatment with anti-ganglioside 2 (GD2) mAb. Survival rates were inferior in older (OS 5-year; 1.5-4.9 years: 61%; EFS 5-year; 1.5-4.9 years: 48%) compared to children younger than 1.5 years (OS 5-year; <1.5 years: 91%; EFS 5-year; <1.5 years: 78%). Predictors of poor OS included stage 4 (hazard ratio, HR OS : 18.12, 95% confidence intervals, CI: 3.47-94.54), N-myc amplification (HR OS : 2.16, 95% CI: 1.40-3.34), no surgical excision (HR OS : 3.27, 95% CI: 1.91-5.61) and relapse/progression (HR OS : 5.46, 95% CI: 3.23-9.24). Similar unfavorable EFS was found for the same subsets of patients. By contrast, treatment with anti-GD2 antibody in high-risk patients was associated with decreased risk of death or unfavorable events (HR OS : 0.11, 95% CI: 0.02-0.79; HR EFS : 0.19, 95% CI: 0.07-0.52). Our results confirm the outstanding prognosis of the early NBL stages, especially in children <1.5 years, and the improved outcomes of the anti-GD2 treatment in high-risk patients. Ongoing high-quality clinical cancer registration is needed to ensure comparability of survival across Europe and refine our understanding of the NBL biology.

Polycystin-1 regulates cell proliferation and migration through AKT/mTORC2 pathway in a human craniosynostosis cell model.

Craniosynostosis is the premature fusion of skull sutures and has a severe pathological impact on childrens' life. Mechanical forces are capable of triggering biological responses in bone cells and regulate osteoblastogenesis in cranial sutures, leading to premature closure. The mechanosensitive proteins polycystin-1 (PC1) and polycystin-2 (PC2) have been documented to play an important role in craniofacial proliferation and development. Herein, we investigated the contribution of PC1 to the pathogenesis of non-syndromic craniosynostosis and the associated molecular mechanisms. Protein expression of PC1 and PC2 was detected in bone fragments derived from craniosynostosis patients via immunohistochemistry. To explore the modulatory role of PC1 in primary cranial suture cells, we further abrogated the function of PC1 extracellular mechanosensing domain using a specific anti-PC1 IgPKD1 antibody. Effect of IgPKD1 treatment was evaluated with cell proliferation and migration assays. Activation of PI3K/AKT/mTOR pathway components was further detected via Western blot in primary cranial suture cells following IgPKD1 treatment. PC1 and PC2 are expressed in human tissues of craniosynostosis. PC1 functional inhibition resulted in elevated proliferation and migration of primary cranial suture cells. PC1 inhibition also induced activation of AKT, exhibiting elevated phospho (p)-AKT (Ser473) levels, but not 4EBP1 or p70S6K activation. Our findings indicate that PC1 may act as a mechanosensing molecule in cranial sutures by modulating osteoblastic cell proliferation and migration through the PC1/AKT/mTORC2 cascade with a potential impact on the development of non-syndromic craniosynostosis.

Venous Thromboembolism Risk and Thromboprophylaxis in Pediatric Neurosurgery and Spinal Injury: Current Trends and Literature Review.

Although the entities of venous thromboembolism (VTE), deep venous thrombosis, pulmonary embolus, and thromboprophylaxis in adult patients undergoing brain tumor and spine surgery, traumatic brain injury and elective neurosurgical procedures are widely elucidated, the same is not valid when pediatric patients are under consideration. An attempt to review the peculiarities of these patients through a comprehensive bibliographic review is undertaken. We performed a narrative summary of the relevant literature dedicated to pediatric patients, centered on traumatic brain injury, the general incidence of thromboembolic disease in this patient population, the role of low molecular weight heparin (LMWH) in the treatment and prophylaxis of VTE, and its role in elective neurosurgical procedures, including spinal operations. Additionally, the risk of deep venous thrombosis in elective neurosurgical procedures is reviewed. Due to inherent limitations of the current studies, particularly a restricted number of patients, our data are underpowered to give a definitive protocol and guidelines for all the affected patients. Our current conclusions, based only on pediatric patients, argue that there is limited risk of VTE in pediatric patients suffering from brain tumors and that the possibility of VTE is very low in children undergoing elective neurosurgical procedures. There is no consensus regarding the exact incidence of VTE in traumatic brain injury patients. LMWH seems to be a safe and effective choice for the "at risk" pediatric patient population defined as being older than 15 years, venous catheterization, nonaccidental trauma, increased length of hospital stays, orthopaedic (including spinal) surgery, and cranial surgery.

The Entity of Cerebellar Mutism Syndrome: A Narrative Review Centered on the Etiology, Diagnostics, Prevention, and Therapeutic Options.

Cerebellar mutism syndrome (CMS), also known as posterior fossa syndrome, is an entity that entails a constellation of signs and symptoms which are recorded in a limited number of pediatric patients who have been operated on mainly for tumors involving the posterior cranial fossa, and more precisely, the region of the vermis. Medulloblastoma seems to constitute the most commonly recognized pathological substrate, associated with this entity. The most prevalent constituents of this syndrome are noted to be a, often transient, although protracted, language impairment, emotional lability, along with cerebellar and brainstem dysfunction. Apart from that, a definite proportion of involved individuals are affected by irreversible neurological defects and long-lasting neurocognitive impairment. A bulk of literature and evidence based on clinical trials exist, which reflect the continuous effort of the scientific community to highlight all perspectives of this complex phenomenon. There are several circumstances that intervene in our effort to delineate the divergent parameters that constitute the spectrum of this syndrome. In summary, this is implicated by the fact that inconsistent nomenclature, poorly defined diagnostic criteria, and uncertainty regarding risk factors and etiology are all constituents of a non-well-investigated syndrome. Currently, a preliminary consensus exists about the identification of a group of diagnostic prerequisites that are managed as sine qua non, in our aim to document the diagnosis of CMS. These include language impairment and emotional lability, as proposed by the international Board of the Posterior Fossa Society in their consensus statement. It is common concept that midline tumor location, diagnosis of medulloblastoma, younger age at diagnosis, and preoperatively established language impairment should be accepted as the most determinant predisposing conditions for the establishment of this syndrome. A well-recognized pathophysiological explanation of CMS includes disruption of the cerebellar outflow tracts, the cerebellar nuclei, and their efferent projections through the superior cerebellar peduncle. Despite the relative advancement that is recorded regarding the diagnostic section of this disease, no corresponding encouraging results are reported, regarding the available treatment options. On the contrary, it is mainly targeted toward the symptomatic relief of the affected individuals. The basic tenet of our review is centered on the presentation of a report that is dedicated to the definition of CMS etiology, diagnosis, risk factors, clinical presentation, and clinical management. Apart from that, an effort is made that attempts to elucidate the paramount priorities of the scientific forum, which are directed toward the expansion our knowledge in the era of diagnostics, prevention, and therapeutic options for patients suffering from CM, or who are at risk for development of this syndrome.

Differential and Common Signatures of miRNA Expression and Methylation in Childhood Central Nervous System Malignancies: An Experimental and Computational Approach.

Epigenetic modifications are considered of utmost significance for tumor ontogenesis and progression. Especially, it has been found that miRNA expression, as well as DNA methylation plays a significant role in central nervous system tumors during childhood. A total of 49 resected brain tumors from children were used for further analysis. DNA methylation was identified with methylation-specific MLPA and, in particular, for the tumor suppressor genes CASP8, RASSF1, MGMT, MSH6, GATA5, ATM1, TP53, and CADM1. miRNAs were identified with microarray screening, as well as selected samples, were tested for their mRNA expression levels. CASP8, RASSF1 were the most frequently methylated genes in all tumor samples. Simultaneous methylation of genes manifested significant results with respect to tumor staging, tumor type, and the differentiation of tumor and control samples. There was no significant dependence observed with the methylation of one gene promoter, rather with the simultaneous presence of all detected methylated genes' promoters. miRNA expression was found to be correlated to gene methylation. Epigenetic regulation appears to be of major importance in tumor progression and pathophysiology, making it an imperative field of study.

Histone Mark Profiling in Pediatric Astrocytomas Reveals Prognostic Significance of H3K9 Trimethylation and Histone Methyltransferase SUV39H1.

Alterations in global histone methylation regulate gene expression and participate in cancer onset and progression. The profile of histone methylation marks in pediatric astrocytomas is currently understudied with limited data on their distribution among grades. The global expression patterns of repressive histone marks H3K9me3, H3K27me3, and H4K20me3 and active H3K4me3 and H3K36me3 along with their writers SUV39H1, SETDB1, EZH2, MLL2, and SETD2 were investigated in 46 pediatric astrocytomas and normal brain tissues. Associations between histone marks and modifying enzymes with clinicopathological characteristics and disease-specific survival were studied along with their functional impact in proliferation and migration of pediatric astrocytoma cell lines using selective inhibitors in vitro. Upregulation of histone methyltransferase gene expression and deregulation of histone code were detected in astrocytomas compared to normal brain tissues, with higher levels of SUV39H1, SETDB1, and SETD2 as well as H4K20me3 and H3K4me3 histone marks. Pilocytic astrocytomas exhibited lower MLL2 levels compared to diffusely infiltrating tumors indicating a differential pattern of epigenetic regulator expression between the two types of astrocytic neoplasms. Moreover, higher H3K9me3, H3K36me3, and SETDB1 expression was detected in grade IIΙ/IV compared to grade II astrocytomas. In univariate analysis, elevated H3K9me3 and MLL2 and diminished SUV39H1 expression adversely affected survival. Upon multivariate survival analysis, only SUV39H1 expression was revealed as an independent prognostic factor of adverse significance. Treatment of pediatric astrocytoma cell lines with SUV39H1 inhibitor reduced proliferation and cell migration. Our data implicate H3K9me3 and SUV39H1 in the pathobiology of pediatric astrocytomas, with SUV39H1 yielding prognostic information independent of other clinicopathologic variables.

Polycystin-1 modulates RUNX2 activation and osteocalcin gene expression via ERK signalling in a human craniosynostosis cell model.

Craniosynostosis refers to the premature fusion of one or more cranial sutures leading to skull shape deformities and brain growth restriction. Among the many factors that contribute to abnormal suture fusion, mechanical forces seem to play a major role. Nevertheless, the underlying mechanobiology-related mechanisms of craniosynostosis still remain unknown. Understanding how aberrant mechanosensation and mechanotransduction drive premature suture fusion will offer important insights into the pathophysiology of craniosynostosis and result in the development of new therapies, which can be used to intervene at an early stage and prevent premature suture fusion. Herein, we provide evidence for the first time on the role of polycystin-1 (PC1), a key protein in cellular mechanosensitivity, in craniosynostosis, using primary cranial suture cells isolated from patients with trigonocephaly and dolichocephaly, two common types of craniosynostosis. Initially, we showed that PC1 is expressed at the mRNA and protein level in both trigonocephaly and dolichocephaly cranial suture cells. Followingly, by utilizing an antibody against the mechanosensing extracellular N-terminal domain of PC1, we demonstrated that PC1 regulates runt-related transcription factor 2 (RUNX2) activation and osteocalcin gene expression via extracellular signal-regulated kinase (ERK) signalling in our human craniosynostosis cell model. Altogether, our study reveals a novel mechanotransduction signalling axis, PC1-ERK-RUNX2, which affects osteoblastic differentiation in cranial suture cells from trigonocephaly and dolichocephaly patients.

Fetal subependymal giant cell astrocytoma: A case report and review of the literature.

BACKGROUND: Subependymal giant cell astrocytomas (SEGAs) appear approximately in 10% of patients with tuberous sclerosis. These tumors are most commonly diagnosed in childhood and adolescence, with in utero diagnosed SEGAs being an extremely rare entity. CASE DESCRIPTION: We present the case of a congenital SEGA detected in an antenatal ultrasound and further investigated with fetal magnetic resonance imaging (MRI) scans at 22 and 32 weeks of gestational age. At 9 days of age, the child underwent craniotomy and partial excision of the tumor, followed by a second more extensive operation 13 days later. The patient was subsequently administered mammalian target of rapamycin inhibitor (everolimus). CONCLUSION: In the latest follow-up MRI, at the age of two, the SEGA remained unchanged. Management of these tumors in neonates is challenging, mainly due to high morbidity and mortality of surgical treatment in these ages.

The 100 Most Cited Papers About Brain Metastases.

BACKGROUND: A vast amount of articles centered on brain metastases have been published. OBJECTIVE: To present the 100 most-cited articles dedicated to brain metastasis and to accomplish a broad literature review. METHODS: In December 2019, we performed a title-focused search using the Thomson Reuters Web of Science database to identify the most cited articles centered on brain metastatic disease. Our search query term was based on using the following algorithm: "brain metastases" OR "brain metastasis" OR "brain metastatic disease" OR "cerebral metastases" OR "cerebral metastasis" OR "cerebral metastatic disease." Afterward, we reviewed the results to certify that they were relevant to the purposes of our research protocol. The 100 most cited papers were chosen and further analyzed. RESULTS: Our search resulted in 11,579 articles, published from 1975 until the completion of our survey. The most cited article, by Patchell et al., was published in 1990, with 1862 citations, and an average of 62.07 citations per year, whereas the last in our list, by Gaspar et al., was published in 2010, with 195 total citations, and an average of 19.50 citations per year. Countries with the highest-cited articles included the United States (75 records), followed by Canada (16 records). CONCLUSIONS: We discovered the top 100 most-cited articles centered on brain metastasis, all of which show a potentially increased level of interest, because they are meaningful scientific reports. In addition, we reviewed the historical development and advances in brain metastasis research and relevant points of interest, alongside the relevant contributions of different authors, fields of special interest, and countries. Many of the most cited articles were written by authors whose specialty was not neurosurgery or by neurosurgeons who were supported by colleagues from other medical fields. As a consequence, many of these articles were not published in neurosurgery-dedicated journals.

Postoperative Tetraplegia to a Child after Cerebellar Pilocytic Astrocytoma Excision at Prone Position: Case Report and Literature Review.

BACKGROUND Various factors have been implicated in the pathogenesis of infarction after posterior fossa surgery such as venous air embolism, patient's position (seated or prone), hyperflexion of the neck, excessive spinal cord traction, cervical canal stenosis, and systemic arterial hypotension. The main aim of this case report was to elucidate a case in which hydrogen peroxide was implicated in a major and systemic complication after a neurosurgical procedure. CASE REPORT We describe the case of a 5-year-old female patient who was admitted to our hospital because of a cerebellar hemispheric astrocytoma associated with obstructive hydrocephalus and accompanied by 2 syringomyelic cavities in the cervicothoracic portion of the spinal cord. Immediately after gross total resection of the lesion, impaired mobility of the upper and lower extremities was observed, a finding that was not consistent with intraoperative neurophysiologic monitoring data. Hydrogen peroxide had been judiciously used to irrigate the resection tumor cavity. In the next few postoperative days, the patient suffered from transient diabetes insipidus and hyperpyrexia, indicative of hypothalamic injury. CONCLUSIONS Neurological evaluation of the patient, after stabilization of her medical condition, revealed residual spasticity of upper and lower extremities, rendering her able to mobilize via the aid of wheelchair only. The most possible pathophysiologic explanation of her neurological deterioration, including hypothalamic dysfunction, was analyzed. The role of hydrogen peroxide as a source of free radical formation, and its co-responsibility for vascular platelet aggregation and vasoconstriction was considered, upon case review, the main responsible etiologic factor.

Edema of the Floor of the Fourth Ventricle Accompanying Shunt Malfunction and Disappearance of It After Shunt Repair: Case Report and Literature Review.

BACKGROUND The ventriculoperitoneal shunt remains, despite recent advances, the mainstay of treatment for hydrocephalus. Although it is used as a routine practice, and besides its recorded and documented safety, it often malfunctions due to a variety of reasons, most commonly referred to as obstruction, breakage, migration and infection. A usual finding of those children suspected to magnetic resonance imaging is the detection of a rim of hyperintensity in the periventricular white matter (halo). CASE REPORT We describe the case of a 7-year-old male patient, treated 4 years ago for an infratentorial ependymoma, who developed hydrocephalus at the time of clinical presentation. During his previous follow-up, he was disease-free but developed clinically evident acute shunt malfunction, accompanied by imaging findings on magnetic resonance imaging (MRI) consisting of interstitial edema surrounding the supratentorial ventricular system, with additional involvement of the floor of the fourth ventricle. This peculiar and novel imaging finding subsided after successful management of hydrocephalus. CONCLUSIONS At present, contemporary computed tomography and MRI modalities constitute the gold standard in order to assess and follow-up patients with established hydrocephalus. Periventricular interstitial edema is a well-established imaging feature of acute hydrocephalus and, in cases of ventriculoperitoneal shunt, of shunt malfunction. Besides that, a newly described, to the best of our knowledge, imaging feature could be the distinction of that signal alteration at the floor of the fourth ventricle. It seems to have prognostic significance regarding the adequacy of management of hydrocephalus, as it disappeared after its successful treatment.

Giant intracranial congenital hemangiopericytoma/solitary fibrous tumor: A case report and literature review.

BACKGROUND: Hemangiopericytoma and solitary fibrous tumor (HPC/SFT) are considered to be one category according to the WHO 2016 classification of central nervous system tumors. HPC/SFT are subdivided into infantile (congenital) and adult type. Both are extremely rare entities, with little knowledge about etiology, prognosis, and optimal therapeutic strategy. CASE DESCRIPTION: A 10-day-old girl was referred to our neurosurgical department due to hypotonia, palsy of the right oculomotor nerve, and prominent frontal fontanel. Imaging studies revealed a large occupying mass in the right middle cerebral fossa and the suprasellar cisterns. Only a subtotal resection of the tumor was possible, and postoperatively, she underwent chemotherapy (CHx). After a 3-year follow-up, the girl has minimum neurologic signs and receives no medications, and she can walk when she is supported. CONCLUSION: Congenital HPC/SFT is considered to have a benign behavior with a good prognosis. Treatment with gross total resection, when it is feasible, is the key to a good prognosis and low rates of recurrence. However, there is no consensus on the therapeutic strategy of a HPC/SFT, which is difficult to be completely resected. Literature lacks a therapeutic algorithm for these tumors, and thus, more clinical studies are needed to reach a consensus.

Herpes Simplex Encephalitis Initially Erroneously Diagnosed as Glioma of the Cerebellum: Case Report and Literature Review.

BACKGROUND: Herpes simplex encephalitis caused by herpes simplex has an estimated annual prevalence in the order of 1 in 250,000 to 500,000 patients and is considered to be the most usually encountered nonendemic pathogenic cause of lethal encephalitis in well-developed countries. There are a few cases reported in the literature in which a diagnostic dilemma between was raised between herpes simplex encephalitis and brain glioma and a definitive diagnosis was difficult to obtain. CASE DESCRIPTION: We report the case of a 5-year-old girl with a previous medical history of premature thelarche. As a part of her investigation, magnetic resonance imaging of the brain was performed, which revealed a space-occupying lesion of the posterior fossa. Magnetic resonance spectroscopy was performed, which advocated for the diagnosis of glioma. She was operated on, but the histopathologic analysis failed to verify the imaging findings. Herpes simplex virus (HSV) 1 was detected in cerebrospinal fluid (CSF) samples. Follow-up magnetic resonance imaging scans illustrated the progression of the disease. CONCLUSIONS: The accumulation of data regarding CSF sample analysis, electroencephalography, brain biopsy, and imaging findings, along with the progression of the clinical picture of our patient, verified the diagnosis of HSV encephalitis. When confronted with confounding data that can pose a diagnostic dilemma between HSV encephalitis and glioma, brain biopsy and polymerase chain reaction of CSF samples could be able to verify the definitive diagnosis. When interpreting our results, we always have to consider the evolution of the clinical picture.

Primary, Dural-Based, Ewing Sarcoma Manifesting with Seizure Activity: Presentation of a Rare Tumor Entity with Literature Review.

BACKGROUND: Primary Ewing sarcoma arising from the calvarial bone and/or underlying dura matter are relatively rarely reported in the literature. Even rarer are considered to be those that originate from the dura and proliferate in both directions, toward the brain parenchyma and through the dura invading the overlying bone. CASE DESCRIPTION: We report the case of a girl aged 11 years who presented with an ictus of generalized tonic-clonic seizures, without known focal neurologic deficit. Neuroradiologic work-up verified the existence of a tumor in the right fronto-parietal area of the brain, invading both the bone and brain parenchyma and emanating from the dura. No other tumor location was discovered after radiologic work-up, and gross total resection was undertaken followed by adjuvant radiation therapy and chemotherapy. CONCLUSIONS: The patient had an uneventful neurologic recovery without persistent neurologic deficit. One year after the operation, with the patient under close clinical and radiologic surveillance, no recurrence of the disease was detected. This case illustrates an extremely uncommon location of primary Ewing sarcoma, along with a constellation of clinical signs and symptoms that are fairly uncommon for this location of this rare disease entity.

Fibrous dysplasia of occipital and temporal bone. A case report.

Fibrous dysplasia is a rare non-malignant condition where fibrous tissue replaces the normal bone architecture. Involvement of temporal and occipital bones is exceptionally rare and is associated with unique complications. A 10-year-old boy presented with right retroauricular enlargement and pain. Imaging studies and biopsy revealed fibrous dysplasia of the temporal and occipital bones. There was no hearing loss or sequelae arising from posterior fossa compression. The patient was discharged with follow-up instructions. Only 10 cases of occipital bone fibrous dysplasia have been reported in the medical literature. Occipital bone fibrous dysplasia can be complicated with Chiari malformation and syringomyelia while temporal bone involvement is associated with hearing loss. These potential developments require close follow-up that includes detailed neurologic examination, imaging and audiology.

Intraparenchymal Pericatheter Cyst after Cerebrospinal Fluid Shunt: A Rare Complication with Challenging Diagnosis - Case Presentation and Review of the Literature.

An intraparenchymal pericatheter cyst is a rare complication of ventriculoperitoneal shunt, which is not well described yet. Due to its rarity, lack of characteristic symptoms and radiological features that often mimic brain tumors or abscesses, especially in head computed tomography without contrast can be easily misdiagnosed. We report the case of a 9-year-old girl who was admitted to a peripheral hospital due to severe headaches and vomiting. The child had a history of craniotomy and ventriculoperitoneal shunt for posterior fossa tumor, performed in our department, 4 years earlier. The patient underwent a brain magnetic resonance imaging (MRI) scan and transmitted to our hospital with the diagnosis of brain tumor. However, a closer look at the MRI established the diagnosis of intraparenchymal pericatheter cerebrospinal fluid cyst; hence, the patient underwent shunt revision and cyst drainage. We researched the literature and described 20 reported cases, discussing the pathophysiological mechanisms, the radiological features, and the optimal treatment of this interesting, yet a challenging complication.

Torkildsen shunt as a salvage procedure for an infant with post-hemorrhagic hydrocephalus.

INTRODUCTION: Torkildsen operation is a ventriculo-cisternal shunt that diverts the cerebrospinal fluid flow from one of the lateral ventricles, via a ventricular catheter, to the cisterna magna of the posterior fossa. It is the first described operation of CSF diversion for the treatment of hydrocephalus [1] (Scarff, 1963). PRESENTATION OF CASE: We present the case of a premature infant who presented with post hemorrhagic hydrocephalus who underwent several failed CSF diversion surgeries before Torkildsen shunt procedure. The patient overcame the irregularities of CSF circulation that were observed before the operation and his post-operative course was uneventful, in terms of CSF -related complications. DISCUSSION: We summarize the historical data and the technical aspects of the procedure, and we present a brief literature review of the indications and limitations associated with it. CONCLUSION: Torkildsen shunt can be effective in selected patients with hydrocephalus even in the modern era of computed tomography and magnetic resonance imaging. the procedure enables one to avoid a standard ventriculoperitoneal shunt, especially in cases it is not technically feasible.

Primitive synovial sarcoma of suboccipital region in child.

Synovial sarcoma (SS) most commonly affects the lower limbs of males in the third to fifth decades of life, with masses of the head and neck accounting for 3-10% of all cases, mainly as a metastatic lesion. The lack of specific symptoms and radiological features in addition to the diversity of their microscopic aspects may cause confusion in the diagnosis; hence, knowledge of the unusual locations of SSs is very important. The immunohistochemistry, and more recently the cytogenetic studies, contribute to the differential diagnosis. We report the case of a 12-year-old girl with a rare primary SS in the suboccipital region, which underwent complete surgical resection.

Effectiveness of a single intra-articular bone marrow aspirate concentrate (BMAC) injection in patients with grade 3 and 4 knee osteoarthritis.

AIM: To evaluate the clinical efficacy and safety of an intra-articular injection of bone marrow aspirate concentrate (BMAC) as a treatment option for osteoarthritis (OA) of the knee. MATERIALS AND METHODS: Between June 2014 and February 2017, data from 233 patients with knee osteoarthritis treated with BMAC injection at a single center, were retrospectively evaluated. Only patients with idiopathic osteoarthritis were included. Exclusion criteria were post-traumatic osteoarthritis, previous knee surgery, age less than 50 years old or more than 85 years old, active infection, uncontrolled diabetes mellitus, rheumatological or other systemic disease, malignancy, or treatment with immunosuppressive drugs. Bone marrow from the iliac crest was aspirated/concentrated with a standardized technique using a single-spin manual method. Patients were evaluated before and after the procedure, using the numeric pain scale (NPS) and Oxford knee score (OKS). Mean follow-up period was 11 months, range (6-30 months). RESULTS: A total of 121 of 233 patients had completed data as previously defined and were included in the statistical analysis. There were 85 females and 36 males, with mean age 70 years (range 50-85). Compared to baseline, the mean NPS decreased from 8.33 to 4.49 (p < 0.001) and the mean OKS increased from 20.20 to 32.29 (P < 0.001) at final follow-up. There were no complications. CONCLUSION: A single intra-articular injection of BMAC is a safe and reliable procedure that results in clinical improvement of knee OA.

Chromatin remodeling defects in pediatric brain tumors.

Brain tumors are regarded as the most prevalent solid neoplasms in children and the principal reason of death in this population. Even though surgical resection, radiotherapy and chemotherapy have improved outcome, a significant number of patients die in 6-12 months after diagnosis while those who survive, frequently experience side effects and relapses. Several studies suggest that many types of cancer including pediatric brain tumors are characterized by alterations in epigenetic profiles with deregulated chromatin remodeling and posttranslational covalent histone modifications playing a prominent role. Moreover, interplay of genetic and epigenetic changes has been associated to tumor growth and invasion as well as to modulation of patient's response to current treatment. Therefore, detection of tumor-specific histone changes and elucidation of the underlying gene defects will allow successful tailoring of personalized treatment. The goal of this review is to provide an update of genetic and epigenetic alterations that characterize pediatric brain tumors focusing on histone modifications, aiming at directing future molecular and epigenetic therapeutic targeting.