Choroid Plexus Papilloma Research Articles

Endoscopic transcortical expanded transforaminal transvenous transchoroidal approach to third ventricle lesion resection using an endoport

ObjectiveTo investigate the clinical experience and application value of endoscopic resection of lesions in and around the third ventricle using a transcortical expanded transforaminal transvenous transchoroidal approach with an endoport. MethodsClinical data and follow-up results of seven patients who underwent the removal of lesions in the third ventricle and its adjacent area with an endoport-guided endoscopic system from January 2018 to December 2020 in the Department of Neurosurgery, Zhongshan Hospital Affiliated to Fudan University, were analyzed retrospectively. Two other patients from the Affiliated Pediatric Hospital of Fudan University and the Affiliated Hospital of Guizhou Medical University, respectively, were included in the analysis. ResultsA total of nine cases of third ventricle tumors were included in the study, including six women and three men, with an average age of 37.8 years (4–84 years old) and a follow-up time of 6–44 months. These nine tumor cases included two pilocytic astrocytomas, one diffuse midline glioma (H3 K27-altered), two craniopharyngiomas, two choroid plexus (CP) papillomas, one germinoma, and one pineal parenchymal tumor of intermediate differentiation. Total resection was completed in eight cases, with one near-total resection. There were no complications related to the surgical approach, such as epilepsy, aphasia, or hemiplegia. ConclusionsThe endoscope transcortical expanded transforaminal transvenous transchoroidal approach using an endoport can safely and effectively remove third ventricle lesions. This approach can reach a wide area, from the anterior to the posterior third ventricle.

Case Report on Choroid Plexus Papilloma

Choroid Plexus Papillomas (CPPs) is also known as benign but rare central nervous system(CNS) which affect the tufts of villi that make the ventricular system choroid plexus, which is responsible for production of cerebrospinal fluid(CSF). They make up between 0.5-1% in adult and 3-4% of paediatric group.Here we are introducing 11-year-old- female who visited with her parents in paediatric outpatient unit with the complaints of headache in the frontal region and backregion. She had 4-5 episodes of vomiting in previous week, she also developed the double vision since last 2 days. The patient underwent Magnetic Resonance Imaging of the brain and found the evidence of papilla enema in both eyes. Patient went to eye department for Vitreo-retained(VR) surgery. After that client was shifted to ward for the further management where she was administered the appropriate paediatric dose of antiedema and antiepileptic medication and other supportive measures. After treatment, the patient's condition was improved than before. Symptoms such as blurred vision relieved after surgery. These tumours rarely develop in children’s third ventricles, fourth ventricles or CP angle.

The Ipsilateral Interhemispheric Transprecuneal Approach to the Atrium: Technical Considerations and Clinical Outcome on a Series of 7 Patients.

Surgical removal of tumors of the atrium is challenging due to their deep location, vascularization, and to their complex three-dimensional relationships with the highly functional white matter fibers of the region. To assess the feasibility and the effectiveness of the ipsilateral interhemispheric transprecuneus approach (IITA) for tumors involving the atrium and the posterior third of the temporal horn, a retrospective chart review of all patients who had undergone a surgical treatment for intraventricular tumors between January 2008 and January 2017 was performed, and the step-by-step approach is described. Ten patients affected by lesions of the atrium of the lateral ventricle underwent surgical treatment, seven of which were approached through the IITA. The mean age was 42.8 years (range 6-63 years). The symptoms presented included severe, drug-resistant headache (90%), lateral homonymous hemianopsia (50%), seizures (30%), and speech disturbances (30%). Histological examinations revealed seven patients with meningioma (70%), one with a metastasis (10%), one with a choroid plexus papilloma (10%) and one with a cavernoma (10%). In all cases, a gross total removal was obtained. All patients had a significant improvement in their headache. Two patients experienced a worsening of the pre-operative visual disturbances, while two patients had a significant improvement. No patients without pre-operative visual disturbances described a post-operative worsening of visual symptoms. The IITA represents a feasible approach for tumors of the atrium. The three-quarter prone position facilitates the enlargement of the interhemispheric fissure by increasing the working angle and facilitating the exposure of the lateral wall of the atrium.

188: Choroid Plexus Papilloma in a Adult: Case Report

188: Choroid Plexus Papilloma in a Adult: Case Report

Surgical Experience with Lateral Ventricular Choroid Plexus Papilloma in Children

Surgical Experience with Lateral Ventricular Choroid Plexus Papilloma in Children

637 Choroid Plexus Tumours in the Paediatric Population - a Five Year Review

Abstract Aim A systematic, qualitative review of the literature available on choroid plexus tumours (CPTs) in the paediatric population, published within the last 5 years. Method Medline and Embase databases were used to identify suitable papers, and 70 papers were eligible for inclusion. Inclusion criteria: (1) Paediatric population, (2) Choroid plexus lesions of any grade, (3) Human subjects, (4) Abstract available, (5) Author name available, (6) Abstract in English. Results Choroid plexus tumours are rare neuroepithelial tumours. It was found that 74% of CPTs present within the first decade of life. They have a slight male predilection, with a male to female ratio of 1.2:1. The most frequent symptoms found in this study included headache, vomiting, and motor weakness. Both CT and MRI images of CPTs usually demonstrate densely enhancing, multilobulated, intraventricular masses. Choroid plexus tumours can be divided into three histological grades and have been subdivided into 3 methylation groups, which is proposed to be a more accurate classification than histological information alone. The review found that management is one of the most controversial aspects of CPT's. Treatment options include surgical resection, traditional chemotherapy, marrow ablative chemotherapy, and radiotherapy, depending on the case. Conclusions Larger cohorts are necessary for prospective, randomised studies are needed to develop a standardised treatment for paediatric patients with CPTs and improve outcomes. As with many low incidence conditions, there appears to be a vicious cycle of low incidences and poor outcomes, which perpetuate limited research into the area alongside a clinical need for better management.

Characterization of TRPV4-mediated signaling pathways in an optimized human choroid plexus epithelial cell line.

The objectives of these studies were twofold: 1) to characterize the human choroid plexus papilloma (HIBCPP) cell line as a model of the blood-cerebrospinal fluid barrier (BCSFB) via morphology, tightness, and polarization of transporters in choroid plexus epithelia (CPe), and 2) to utilize Ussing-style electrophysiology to elucidate signaling pathways associated with the activation of the transient receptor potential vanilloid 4 (TRPV4) channel involved in cerebrospinal fluid (CSF) secretion. RT-PCR was implemented to determine gene expression of cell fate markers, junctional complex proteins, and transporters of interest. Scanning electron microscopy and confocal three-dimensional renderings of cultures grown on permeable supports were utilized to delineate the morphology of the brush border, junctional complexes, and polarization of key transporters. Electrophysiology was used to understand and explore TRPV4-mediated signaling in the HIBCPP cell line, considering both short-circuit current (Isc) and conductance responses. HIBCPP cells grown under optimized culture conditions exhibited minimal multilayering, developed an intermediate resistance monolayer, retained differentiation properties, and expressed, and correctly localized, junctional proteins and native transporters. We found that activation of TRPV4 resulted in a robust, multiphasic change in electrogenic ion flux and increase in conductance accompanied by substantial fluid secretion. This response appears to be modulated by a number of different effectors, implicating phospholipase C (PLC), protein kinase C (PKC), and phosphoinositide 3-kinase (PI3K) in TRPV4-mediated ion flux. The HIBCPP cell line is a representative model of the human BCSFB, which can be utilized for studies of transporter function, intracellular signaling, and regulation of CSF production.

Incidence and survival of choroid plexus tumors in the United States.

There are limited data available on incidence and survival of patients with choroid plexus tumors (CPT). This study provides the most current epidemiological analysis of choroid plexus tumors from 2004 to 2017 in the United States. Data on 2013 patients with CPT were acquired from the Central Brain Tumor Registry of the United States in collaboration with the Centers for Disease Control and Prevention (CDC) and the National Cancer Institute, from 2004 to 2017. CPT cases were classified by the following pathological subtypes: choroid plexus papilloma (CPP), atypical choroid plexus papilloma (aCPP), and choroid plexus carcinoma (CPC). Frequencies and age-adjusted incidence rates (AAIR) per 100 000 and rate ratios per 100 000 (IRR) were reported for age, sex, race, and ethnicity for each pathological subtype with 95% confidence intervals (95% CI). Using CDC's National Program of Cancer Registries survival database, survival curves and hazard ratios (HRs) evaluated overall survival from 2001 to 2016. CPP had the highest overall incidence (AAIR: 0.034, 95% CI: 0.033-0.036), followed by CPC (AAIR: 0.008, 95% CI: 0.008-0.009) and aCPP (AAIR: 0.005, 95% CI: 0.005-0.006). Incidence was highest among children less than one year old among all subtypes (CPP AAIR: 0.278; aCPP AAIR: 0.140; CPC AAIR: 0.195), reducing as patients aged. Overall survival was worse among patients with CPC, being five times more likely to die compared to patients with CPP (HR: 5.23, 95% CI: 4.05-7.54, P < .001). This analysis is the most current and comprehensive study in the US on the incidence and survival for CPT. Population based statistics provide critical information in understanding disease characteristics, which impact patient care and prognosis.

Incidence and Surgical Outcome of Intraventricular Tumors at a Tertiary Care Hospital in Lahore, Pakistan

Objectives: To determine the incidence and outcome of intraventricular tumors treated micro-surgically at the Punjab Institute of Neurosciences, Lahore, Pakistan.&#x0D; Materials and Methods: A retrospective study of a series of 42 patients with the initial diagnosis of intraventricular tumors who underwent microsurgical resection over a period of 04 years. The extent of resection was decided by post-operative imaging (CT Brain), performed on immediate or 1st post-op day, and by MRI on outdoor follow-up after an average of 4 weeks. Post-operative complications and the Glasgow outcome scale were also recorded.&#x0D; Results: The majority of patients presented with nonspecific symptoms. 47.6% patients presented with headache, nausea/vomiting (40.5%), decreased vision (21.4%), fits (19%) and hydrocephalus (9.52%).29patients (72.5%) underwent microsurgical excision through the anterior transcortical approach, followed by 08 (19.05%) via the posterior transcortical approach. GTR was achieved in 33 (78.57%). Based on histopathology reports, 14 (33.3%) were ependymomas, 11(26.2%) meningiomas, 07 (16.67%) sub-ependymomas, 5 (11.9%) central neurocytomas, and 2(4.76%) Choroid Plexus Papilloma. Significant postoperative intraventricular bleed was noted in 04 (9.52%) patients, minor I/V bleed in 06 (14.28%), hydrocephalus in 07 (16.67%), subdural collection in 02 (4.76%), and motor deficit in 03 (7.15%) patients. Based on Glasgow Outcome Scale, 32 (76.2%) had GOS5/5, 7 (16.67%) with GOS 4/5, while 02 patients expired in the postoperative period.&#x0D; Conclusion: Intraventricular tumors require special neurosurgical consideration. Early diagnosis, better preoperative planning, and an adequate microsurgical approach are necessary to achieve maximum safe resection and improvement in patients’ symptoms and overall condition.

Rare Case of Pediatric Disseminated Choroid Plexus Papilloma: Literature Review and Call for Reclassification

Introduction: Choroid plexus tumors are rare neuroectodermal tumors that arise from the choroid plexus. Choroid plexus papillomas (CPPs) represent the lowest grade of these types of tumors and have a WHO grade I designation. Despite their typical low grade, some CPPs can exhibit aggressive behaviors including parenchymal invasion and dissemination throughout the neuro-axis. Due to their association with the choroid plexus, patients with CPP commonly present with signs and symptoms of hydrocephalus and increased intracranial pressure. Case Presentation: A 2-year-old male presented in extremis with acute hydrocephalus and seizure. He was found to have a large left intraventricular mass with innumerable intraparenchymal and extra-axial cysts throughout his neuro-axis. A literature review revealed five similar disseminated CPP cases with innumerable lesions. This is the youngest reported patient with disseminated CPP and the first with multiple compressive lesions. Following cranial resection and thoracic decompression, the patient’s lesions have remained stable (2 years of follow-up). A literature search of the PubMed/Medline databases was performed using the search terms [“disseminated choroid plexus papilloma” OR “choroid plexus papilloma” OR “metastatic choroid plexus papilloma”] up to March 2021. Articles were then screened for similar patient radiographic presentation and histological diagnosis. To mitigate publication bias, referenced articles were utilized to identify other case reports and case series. Discussion/Conclusion: We describe a rare case of a lateral ventricle CPP with widespread leptomeningeal dissemination causing acute obstructive hydrocephalus and compressive myelopathy requiring cerebrospinal fluid diversion and intracranial resection followed by thoracic spine decompression. This case report serves to broaden knowledge of disseminated CPP and to encourage complete neuro-axis imaging for choroid plexus tumors. Additionally, we propose a naming paradigm refinement that includes radiographic characteristics.

Delayed cerebrospinal fluid ascites following ventriculoperitoneal shunt

Background: Cerebrospinal fluid (CSF) ascites is an abnormal accumulation of CSF within the peritoneal cavity caused by the peritoneum's inability to absorb the CSF, following a ventriculoperitoneal (VP) shunt surgery. Excessive CSF production (e.g, choroid plexus papilloma and choroid plexus villous hypertrophy), high CSF protein secondary to chronic infection (e.g. tuberculosis), and brain tumours (e.g, optic gliomas and craniopharyngiomas) have all been suggested as contributing factors to the formation of CSF ascites. Peritoneal inflammation as a result of several shunt revisions or some non-specific inflammatory reaction to shunt material has also been explored.&#x0D; Case Presentation: A 3-year-old girl with lumbar myelomeningocele and delayed CSF ascites following VP shunt is reported. Therapeutic paracentesis was employed to relieve abdominal distension, although recurring accumulation was common. The VP shunt was removed and instead of a Ventriculo-atrial shunt, she underwent Endoscopic Third Ventriculostomy (ETV). CSF ascites gradually disappeared after ETV over a two-week period.&#x0D; Conclusions: Abdominal paracentesis to relieve ascites and conversion of a Ventriculoperitoneal shunt to a Ventriculo-atrial shunt are commonly used to treat CSF ascites, however Endoscopic Third Ventriculostomy, where feasible, is another alternative treatment that can be performed to treat this condition.

LINC-24. Survival and genetic evaluation of patients diagnosed with choroid plexus tumor treated at a Brazilian institution

INTRODUCTION: Choroid plexus tumors (CPT) are rare intraventricular neoplasms of epithelial origin. They usually occur in the 2nd year of life, corresponding to 0.4-0.6% of intracranial tumors in this age group. They are classified, according to WHO 2021: choroid plexus carcinoma (CPC), atypical choroid plexus papilloma (ACPP) and choroid plexus papilloma (CPP). Li-Fraumeni syndrome (LFS) is present in 50% of patients with CPC. In Brazil, the TP53p.R337H mutation affects 0.3% of the population in the South/Southeast. OBJECTIVE: Evaluate the genetic assessment and overall-survival (OS) of patients with CPT treated at IOP/GRAACC/UNIFESP. PATIENTS/METHODS: Between 1995-2021, 48 patients were diagnosed with CPT in our institution, 27 CPC, 18 CPP and 3 ACPP. From 2012-2021 patients were referred for genetic evaluation, 16 of which had CPC (2 had previously CPP). Family history for neoplasms was present in 87.5%, 37.5% compatible with Li-Fraumeni Syndrome (LFS) of which 50% with positive mutations. The molecular investigation of TP53 gene in patients with CPC was performed and positive in 62,5%:R337H(6 patients), R110C*, R158H*, H179R*, R196* (*1 patient each). For those with R337H, p53 protein immunohistochemistry resulted in 90-100% positivity. Treatment strategies consisted of surgery with gross total resection being achieve in all ACPP, 94,4% CPP and 55,5% CPC. Chemotherapy was performed in only 1 case of ACPP and all CPC with a variety of schemas, including high dose of chemotherapy and autologous bone marrow transplant for slow responders or recurrent disease. The three- and five-years OS for CPC was 72.5% and 61.7%, respectively. For CPP and ACPP 5y OS was 100%. CONCLUSION: The present study is in agreement with the literature showing an excellent survival for CPP and ACPP but an inferior outcome for patients with CPC and TP53 mutation despite being assisted by a well-prepared multidisciplinary team with an adequate treatment.

RARE-26. Evaluating the clinical utility of DNA methylation profiling for choroid plexus tumors

INTRODUCTION: Choroid plexus tumors (CPT) are rare, potentially aggressive CNS tumors with defined histologic criteria for grading. In recent years, several patients within our practice have demonstrated discordance between histological diagnosis and clinical behavior. DNA methylation profiling has emerged as a potential diagnostic adjunct for aiding clinical planning and treatment approach. In this study, we sought to retrospectively evaluate the clinical utility of DNA methylation profiling within our cohort of patients with CPT. METHODS: We performed a retrospective chart review of all patients with choroid plexus tumors treated at Dana-Farber / Boston’s Children’s Cancer and Blood Disorder Center between 1990-2021, evaluating the histology, treatment approach, and clinical outcome. Available tissue samples were sent to the National Institute of Health for DNA methylation profiling. RESULTS: Seventeen patients with CPT were identified. Median age at diagnosis was 1.8 years (range: 0.4-27.7). Histologic diagnosis included choroid plexus papilloma (CPP; n=4), atypical choroid plexus papilloma (aCPP; n=5), and choroid plexus carcinoma (CPC, n=8). DNA methylation in an initial subset placed these tumors with the pediatric type A (n=5), pediatric type B (n=6), and adult (n=1) subgroups. For one patient, methylation profiling returned as unclassifiable (possibly representing an alternative diagnosis). Discrepancies with the histologic grade were noted in several cases: one patient diagnosed with CPP grouped with pediatric type B CPT on methylation analysis, had rapid recurrence, and a diagnosis of CPC was made on a re-resection specimen; another patient with aCPP with concerning features was classified as pediatric type A by methylation, and is without evidence of disease after initial complete resection. Survival outcomes based on histologic diagnosis and molecular subgroups are compared and reported. CONCLUSION: DNA methylation profiling is a useful tool for the diagnosis of CPT and may have the potential to guide clinical planning and management.

PATH-11. Detection of genetic and epigenetic alterations in Liquid Biopsies from pediatric brain tumor patients

Abstract BACKGROUND: Liquid biopsies (LBs) hold great promise as a non-invasive method for tumor detection and disease monitoring. Their application in pediatric neuro-oncology patients has been challenging due to the blood-brain barrier limiting the amount of circulating tumor DNA (ctDNA) and low volumes of cerebrospinal fluid (CSF) and serum samples. Here, we assessed the feasibility of LBs in a pediatric brain tumor cohort (n=12 patients) by adapting pre-analytical protocols to low cell-free DNA (cfDNA) input and bioinformatic pipelines for genome-wide analyses. METHODS: Genomic DNA isolated from tumor tissues, including medulloblastoma (n=6), ependymoma (n=4), low-grade glioma (n=1), and choroid plexus papilloma (n=1), and cfDNA isolated from matched CSF and serum samples were subjected to low-coverage whole genome sequencing (lcWGS) and the EPIC DNA methylation array. For methylation analyses, samples were prepared using both traditional bisulfite- and recently developed enzymatic-based methylation conversion. Molecular tumor (sub)type predictions were performed using the Heidelberg Brain Tumor Classifier. RESULTS: lcWGS revealed tumor-specific copy number variations (CNVs) in both CSF and serum samples. The detection rate of tumor-specific CNVs (median 92% vs. 23%) and the ctDNA fraction (median 31% vs. 1.5%) were higher in CSF vs. serum samples. Bisulfite-converted as well as enzymatically converted tumor DNA and cfDNA samples could be readily analyzed using the Heidelberg Classifier. In comparison to bisulfite-based conversion, enzymatic-based conversion improved the quality of methylation analyses for minimal input cfDNA samples. CONCLUSIONS: Our results highlight the feasibility of liquid biopsies from both CSF and serum in brain tumor patients. In contrast to CNV-based tumor detection from serum samples, ctDNA analysis from CSF allowed a more comprehensive genetic and epigenetic profiling which is expected to assist in less-invasive tumor classification, identification of drug targets, or the investigation of tumor evolution. Altogether, this study provides the rationale for further implementation of LBs in pediatric neuro-oncology.

TBIO-12. Screening for Cancer Predisposition Syndromes in Pediatric Neuro-Oncology Patients: a Single Institution Experience

BACKGROUND: Traditional screening for cancer predisposition syndromes centers on family history, phenotypic features, and tumor histology. With expanded accessibility of next generation sequencing, identification of de novo germline mutations is increasing and the predictive value of family history has become less clear. While identification of germline mutations often affects care of pediatric neuro-oncology patients, germline sequencing is not currently standard of care. We hypothesize that routine screening for germline mutations in pediatric neuro-oncology patients reveals unsuspected cancer predisposition syndromes and impacts care. METHODS: A retrospective analysis was performed on pediatric neuro-oncology patients at a single institution who had targeted next generation sequencing of approximately 500-cancer associated genes (UCSF500) on tumor and paired germline DNA. We determined the proportion of patients with germline mutations and assessed impact on future screening and current tumor treatment. We interrogated clinical notes, family history, and interviewed treating physicians to determine if predispositions were previously suspected. RESULTS: Between June 2015-December 2019, 187 patients had paired testing; of these 29 (16%) harbored germlines mutations that were pathogenic or likely pathogenic. Germline mutations were found in patients with high-grade glioma (n=12), low-grade glioma (n=7), medulloblastoma (n=4), ATRT (n=2), and choroid plexus papilloma (n=1). Known cancer predisposition syndromes were identified or confirmed in 18 patients. Of these, the most common alterations were in TP53 (n=6), CHEK2 (2), NF1 (n=2), SMARCB1 (n=2), and PTEN (n=2). Patients were referred to genetic counseling in 26 cases and malignancy screenings were implemented in 25 cases. Germline findings affected malignancy treatment in 10 cases, most often through use of targeted therapeutics or avoidance of radiation. CONCLUSIONS: In our series, we found that 16% of pediatric neuro-oncology patients harbored germline mutations, the majority of which were associated with cancer predisposition syndromes. These results support standardizing screening for pathogenic germline mutations in pediatric neuro-oncology patients.

RARE-27. Treatment and outcomes in atypical choroid plexus papilloma: a single institution experience

BACKGROUND: Atypical choroid plexus papillomas (aCPP) are rare central nervous system (CNS) tumors often occurring in very young children. While surgical resection has been a mainstay of therapy, there is no consensus and limited data on the treatment of relapsed or metastatic tumors. METHODS: Retrospective review of the treatment and outcome of patients diagnosed with aCPP since 2011 was performed. RESULTS: Of the seven patients, 4 were male and 3 were female with a median age of 3 years at diagnosis (range: antenatal to 18 years old). All non-metastatic patients (six) were treated with surgery and all achieved gross total resection. Two patients had diffuse leptomeningeal contrast enhancement on diagnosis MRI that resolved after resection of primary tumor alone. One patient developed local relapse underwent re-resection with a GTR then was treated with 4 cycles of chemotherapy based on CPT-SIOP-2000 protocol (carboplatin, etoposide) and has not had further relapse in 24 months. One patient had metastatic disease at the time of diagnosis. They were treated with adjuvant chemotherapy, which stabilized disease for 36 months until they had progression. Additional four cycles were given and has again stabilized disease now 8 months from completion of that therapy. One non-metastatic patient died of unknown causes 28 months from diagnosis. CONCLUSIONS: Surgical resection remains the standard of care for patients with aCPP. However, chemotherapy based on the SIOP backbone may be useful to reduce the need for or to delay radiation therapy in select patients in the relapsed or metastatic setting.

EPID-02. Survival Experience in Pediatric Patients of Central Nervous System (CNS) Tumour in Canada

Established in 2016, the Brain Tumour Registry of Canada Surveillance Research Collaboration aims to address the lack of detailed information on CNS tumours in Canada. Using Canadian Cancer Registry (CCR) data with linked vital status, we present survival estimates for all primary CNS tumours (excluding Quebec) among pediatric patients (age 0-14). Pediatric patients diagnosed with primary CNS tumours during 2010-2017 were included. Vital status was obtained by Statistics Canada through linkage to the Canadian Vital Statistics Database and the income tax returns file, with a cut-off date of December 31, 2017. We used the Pohar-Perme method to estimate the net survival rate (NSR) through the period approach. International Classification of Diseases for Oncology (3rd edition) site/histology codes were grouped into 25 histological categories, irrespective of tumour behaviour, according to the schema developed by the Central Brain Tumor Registry of the United States. Of 1725 pediatric CNS tumours, the 1-, 2- and 5-year NSR are 0.89 (95%CI 0.87-0.90), 0.84 (95%CI 0.81-0.86) and 0.80 (95%CI 0.78-0.82), respectively. All non-malignant CNS tumours have a median survival over 8 years. The 5-year NSR range from 0.90 (95%CI 0.47-0.99) for unique astrocytoma variants, 0.95 for tumour of sellar region (95%CI 0.85-0.98) and germ cell tumours, cysts and heterotopias (95%CI 0.67-0.99), to 1.0 for choroid plexus tumours, tumours of cranial and spinal nerves, and meningioma. For malignant CNS tumours, NSR vary greatly depending on histology grouping. 5-year NSR from lowest to highest are glioblastoma (0.10, 95%CI 0.03-0.23), anaplastic astrocytoma (0.19, 95%CI 0.05-0.40), glioma not otherwise specified (0.54, 95%CI 0.46-0.62), embryonal tumours (0.72, 95%CI 0.65-0.79), diffuse astrocytoma (0.74, 95%CI 0.59-0.85), ependymal tumours (0.78, 95%CI 0.67-0.87), germ cell tumours, cysts and heterotopias (0.85, 95%CI 0.70-0.93) and pilocytic astrocytoma (1.0). We report the most comprehensive and up-to-date data on the pediatric primary CNS tumour survival experience in Canada.

RARE-21Sox2 plays an important role in choroid plexus tumor development

Choroid plexus (CP) tumors are rare primary brain neoplasms found most commonly in children and are thought to arise from CP epithelial cells. Sox2 is a transcription factor that not only plays a role in development in the ventricular zone, CP, and roof plate, but also contributes to cancer stemness, tumorigenesis, and drug resistance. Gene expression studies demonstrate aberrant Sox2 expression in human CP tumors, suggesting a role in tumor development. A subset of CP tumors exhibit abnormal NOTCH pathway activity. Using animal models, we previously show that sustained NOTCH activity leads to CP tumors. Immunofluorescence, RT-qPCR, and RNA scope assays have revealed increased Sox2 levels in NOTCH-driven CP tumors compared to wild type CP in mice. To investigate the role of Sox2 in CP tumors, we eliminated Sox2 expression in NOTCH-driven CP tumors. Loss of Sox2 almost completely blocked NOTCH-driven CP tumor growth in these mice, supporting a role for Sox2 in these tumors. Ciliation regulation is one proposed functional pathway for tumorigenesis in CP tumors. Using immunofluorescence assays for cilia (ARL13b) and aquaporin transport protein 1 (AQP1) in combination with super resolution microscopy, we observe a stark contrast between wild type CP epithelial cells which are multiciliated and homogeneously express AQP1, indicative of normal epithelial differentiation, compared to NOTCH-driven CP tumors consisting of mono-ciliated cells with loss of AQP1 expression. In Sox2-deficient NOTCH-driven CP tumors, we observe tumor cells remain mono-ciliated and AQP1-negative, indicating that Sox2 loss does not affect the ciliation machinery. Together this warrants further study into the mechanisms of Sox2 functions in CP tumors. By unraveling the role of Sox2 in CP tumors, we may better understand their origin and biology to ultimately design improved treatment options.

The epidemiology and current treatment of pediatric choroid plexus carcinoma: An analysis of the national cancer database.

e14024 Background: Choroid Plexus Carcinoma (CPC), a subtype of choroid plexus tumors (CPT), is a rare central nervous system neoplasm mostly affecting the pediatric population. The epidemiology of CPC is poorly understood due to the rarity of the disease. By analyzing the National Cancer Database (NCDB), we describe the demographic and social factors that influence the risk and current treatment of the cancer. Methods: We conducted a retrospective cohort analysis utilizing the 2018 National Cancer Database (NCDB) and included patients with Choroid Plexus Carcinoma with a histology-confirmed WHO grade III tumor, between ages 0-99 years (N = 202). Analysis was completed for the frequency of cases, types of treatment received, and overall survival within the pediatric population (age &lt; 18 years, N = 139) and the adult population. Demographic factors were analyzed using Pearson Chi-squared tests, and survival was estimated using Kaplan-Meier curves. Results: The majority of the cases analyzed were white (55.4%), male (54%), and pediatric patients (66.8%, mean age at diagnosis = 15.17 years) with an average Charlson-Deyo Score of 0.24. The mean age at diagnosis of the pediatric population was 2.34 years (min = less than 1 years old/diagnosed in utero, max = 16, std. deviation = 3.84) while the mean age at diagnosis of the adult population was 43.49 years (min = 18, max = 84, std. deviation = 18.23.) The most common primary site for CPC was malignant neoplasm of the cerebral ventricle (87.6%) followed by malignant neoplasm of the brain stem (5.9%). Surgical procedure of the primary site was performed in 92.6% of cases including local excision, subtotal resection, resection, radical resection, partial resection of a lobe of brain, lobectomy, and surgery NOS. Radiation was not used 71.3% of the time, but was more than three times as likely to be used in the adult population after surgery than in the pediatric population after surgery (44.4% vs 14.4%, p value &lt; 0.001). Most patients received chemotherapy (53%) with the administration of chemotherapy higher in the cohort less than 18 years old (69.8% versus 15.9%, p value &lt; 0.001). Multiagent chemotherapy was administered as the first course of therapy as the top chemotherapeutic choice (86%) especially among the pediatric population (88.6%) compared to the adult population (60%) Palliative care was not provided in any of the cases. There was no statistical significance difference between the general survival of CPC between the pediatric and adult population. Conclusions: Historically, CPC is known as a pediatric cancer, but this NCDB study suggests that the frequency of the adult population affected is not negligible (31.2%). There is a difference regarding the current treatment of CPC in the pediatric versus adult population. Further study is needed to determine the impact of treatment and the importance of socioeconomic factors on the survival of CPC.

Choroid plexus carcinoma in a dog—Case report

AbstractObtaining a conclusive definitive diagnosis for an intra‐ventricular tumour in a dog can be challenging. In doing so, all differential diagnoses should be considered. Differentiation between choroid plexus tumours (CPTs) (a choroid plexus papilloma, atypical choroid plexus papilloma or choroid plexus carcinoma) and gliomas, including ependymoma, oligodendroglioma and astrocytoma should be considered. Histopathologic features and immunohistochemistry are essential in the differentiation between intra‐ventricular tumours. A 4‐year‐old Boerboel dog presented with a left head tilt and a wide range of nonspecific clinical abnormalities not limited to weight loss, depression and marked bradycardia. MRI proved useful in providing a diagnosis of an intra‐ventricular tumour and demonstrated the potential of choroid plexus carcinomas (CPCs) to metastasize. In this case, the histological features displayed malignancy with invasion into the neuroparenchyma, drop metastasis and immunohistochemistry with E‐cadherin‐positive result that assisted with differentiation of CPC from other tumours.