Primary papillary epithelial tumor of the sella: a case report of an emerging tumor type.

Primary papillary epithelial tumor of the sella (PPETS) is a newly described tumor entity with prototypical location in the sella. Only two case series with ten cases have been described so far. These tumours have a typical papillary architecture with bland nuclear features, TTF-1 immunopositivity and low MIB-1-labelling index. Many of these tumours were previously assigned under the category of 'ectopic choroid plexus papilloma'. PPETS expands the group of TTF-1 positive tumours of the central nervous system. Histomorphology plays an essential role in making this diagnosis. We report a case of 44-year-old female with a sellar mass lesion, who presented with progressive loss of vision and diagnosed as primary papillary epithelial tumor.

Paediatric choroid plexus carcinoma: a retrospective case series from Karachi.

The objective of this study is to report clinical, radiological, and histopathological characteristics of three paediatric patients diagnosed as Choroid plexus carcinoma seen at our hospital, between 2015 and 2020. Three patients were diagnosed with choroid plexus carcinomas between 2015 and 2018. The mean age at diagnosis was 1.3 years (range 8 months to 1.5 years). All the three patients had subtotal resection and received adjuvant chemotherapy. One patient also received adjuvant radiotherapy. Despite these treatment measures, residual disease was noted in all three patients and two patients were subsequently treated on palliative care grounds. The average duration of follow-up after the first surgery for all three patients was approximately 33 months. Attaining satisfactory outcome in patients with CPC is challenging. Our case series reflects the difficulty in achieving gross total resection and ensuring that the disease does not recur.

Choroid plexus papilloma in a mature cystic teratoma of ovary: A rare case report.

Mature cystic teratoma of the ovary is the most common type of germ cell tumor. It constitutes approximately 20% of all ovarian neoplasms. As a rare occurrence, however, several types of benign and malignant tumours developing secondarily in dermoid cysts have been reported. Those of central nervous origin are almost exclusively gliomas of astrocytic, ependymal or oligodendroglial lineage. Choroid plexus tumors are unusual intracranial tumors which comprised of only 0.4-0.6% of all brain tumors. These are neuroectodermal in origin and similar in structure to a normal choroid plexus in the form of multiple papillary fronds mounted on a well vascularized connective tissue stroma. The present case report highlights the presence of a choroid plexus tumor in a mature cystic teratoma of the ovary in a 27-year-old woman who came for safe confinement and cesarean section.

Malignant congenital orbital teratoma: Glioblastoma multiforme with primitive neuronal pattern and choroid plexus papilloma: A rare diagnosis at an unusual age.

Childhood orbital teratomas are usually congenital lesions that are most often present at birth with progressive, massive unilateral proptosis. During the routine controls of 27-year-old woman between 26-27th weeks of pregnancy her fetal ultrasonography (USG) revealed a mass in the eye of the fetus, and termination was recommended. The family refused the termination option and in the 37th week of pregnancy, vaginal delivery is performed in an external medical center. The mass in the baby's eye was surgically removed. Microscopic examination revealed disorganized ocular tissues, adipose tissue, microcalcification, nerve plexuses as well as areas of neuronal nodules including hypercellular areas, palisatic necrosis, and microvascular proliferation. The immunprofile--patchy GFAP staining in the areas of cellular epithelioid and spindled cells that also show an focal and sparse expression p53 staining and a high proliferation rate in Ki67 staining--confirmed the hematoxylin-eosin (HE) impression of a teratoma with a component of glioblastoma (GBM). In this unique presentation of a malignant orbital teratoma with a GBM, we have identified three tumor components: (1) GBM component, (2) nodules of neuroglial tissue with mature neurons and BRAF mutation, and (3) papillary proliferation possibly representing a choroid plexus papilloma.

Intra-fourth-ventricular choroid plexus papilloma miming ependymoma.

ABSTRACT: Choroid plexus papilloma (CPP), a low incidence central nervous system (CNS) tumor, typically develops as an intraventricular neoplasm arising from the epithelium of the choroid plexus. Infratentorial CPP is predominantly clustered in adults with roughly 70% in the fourth ventricle, while supratentorial CPP commonly found in the lateral ventricles, is the most frequent location in children. The clinical and imaging features of CPP are not typical and may induce the misdiagnosis as other types of primary brain tumors. In this paper, we described a fourth-ventricular CPP that was misdiagnosed as ependymoma despite the manipulation of groundbreaking magnetic resonance imaging (MRI) sequences. These findings indicated that CPP should be considered when performing the differential diagnosis of intraventricular neoplasms.

CSF Rhinorrhea: A Rare Clinical Presentation of Choroid Plexus Papilloma.

Choroid plexus papilloma (CPP) is a rare brain tumour occurring mostly in infants and children. Most CPPs are intraventricular and present with symptoms and signs of increased intracranial pressure (ICP). This case report describes a middle-aged female who presented with spontaneous cerebrospinal fluid (CSF) rhinorrhea from a tumour located in the cerebellopontine angle (CPA). She underwent craniotomy with subtotal tumour resection and remained progression and rhinorrhea-free for several years. Upon clinical progression, the patient was treated with Cyberknife stereotactic radiosurgery. The patient clinically improved and demonstrated a favourable radiologic response to radiosurgery.

Pediatric atypical choroid plexus papilloma: Clinical features and diagnosis.

OBJECTIVE: Atypical choroid plexus papilloma (aCPP) is a newly introduced subtype of choroid plexus tumors (CPTs) defined by the World Health Organization (WHO) in 2007 and is characterized by intermediate characteristics between choroid plexus papilloma (CPP) and choroid plexus carcinoma (CPC). Currently, the available data describing the clinical features of aCPP in children are limited. METHODS: We performed a retrospective review of 24 pediatric patients with CPTs in our institute and focused on the clinical, radiological and histopathological features of 9 patients with aCPP. RESULTS: The median age of aCPP patients was 12 (3-144) months, which was younger than the age of CPP patients (36 (5-132) months, P < 0.05). Of the 9 aCPPs, there were 4 cases of giant masses in the cerebral hemisphere, which was significantly higher than that in CPPs (44.4 % vs 0.0 %, P < 0.05). According to MRI analysis, cysts and necrosis (66.7 % vs 16.7 %, P < 0.05), peritumoral edema (55.6 % vs 8.3 %, P < 0.05) and blurred borders (55.6 % vs 8.3 %, P < 0.05) were more common in aCPPs than in CPPs. T1WI isointense signals were mainly observed in aCPPs and CPPs (aCPP66.7 % vs CPP58.3 %, P >0.05), while T2WI slightly low signals were more common in CPPs (CPP41.7 % vs aCPP0%, P < 0.05); moreover, the tumor volume of aCPPs was significantly larger than that of CPPs (aCPP78.3 cm3 vs 8.4 cm3, P < 0.05). For the DWI sequence scans, isointense signals were more common in aCPPs (aCPP77.8 %>CPP25.0 %, P < 0.05), while slightly low signals were more common in CPPs (CPP58.3 %>aCPP0%, P < 0.05). Both aCPPs and CPPs mainly showed homogeneously strong enhancement (aCPP66.7 % vs CPP91.7 %, P > 0.05). Interestingly, 1 aCPP showed annular enhancement. For the pathological and immunohistochemical studies, the Ki67 proliferation index was significantly higher in aCPPs than in CPPs (13 % vs 6%, P < 0.05), and the S-100(+)/Vim(+)/Syn(+) positive rate was higher in aCPPs (58.3 % vs 11.1 %, P < 0.05). CONCLUSIONS: aCPP shows some distinctive clinical features compared with CPP, such as younger age, larger tumor size, more frequent necrosis and peritumoral edema, blurred borders, slightly low signals on T2WI and isointense signals on DWI, and a higher S-100(+)/Vim(+)/Syn(+) positive rate, which may provide more valuable evidence for differential diagnosis and clinical decisions surrounding aCPP.

Extracerebral choroid plexus papilloma in the pharynx with airway obstruction in a newborn: a case report.

BACKGROUND: Choroid plexus papillomas (CPPs) are rare, usually benign, neoplasms originating in the central nervous system. In this study, we present the first case of a giant airway-obstructing CPP in the pharynx of a newborn. CASE PRESENTATION: A cystic mass located in the pharynx was noted in a fetus at the 29th week of gestation. Elective cesarean section was performed at the 38th week of gestation with successful intubation and ex utero intrapartum treatment. On computed tomography, there was a huge airway-obstructing cystic mass in the choana and pharynx. Elective surgery with total excision was performed, and histological examination confirmed the diagnosis of CPP. CONCLUSION: We report the first case of an extracerebral airway-obstructing CPP in the pharynx of a newborn. Radiologic examinations are not enough for the diagnosis of CPPs, and complete excision of the tumor with histological confirmation is indispensable for accurate diagnosis and treatment.

Choroid plexus papilloma in extragonadal teratoma with predominantly neurogenic elements: a case report and review of the literature.

BACKGROUND: Teratoma is a germ cell tumor that develops gonadal or extragonadal. Benign or malign somatic tumors can develop in teratoma. Choroid plexus papilloma is a benign, grade I intraventricular neoplasm that occur mostly in children. Choroid plexus papilloma in a teratoma is not often seen. CASE: We present the fifth case of a choroid plexus papilloma in a teratoma in the English literature. It was extragonadal and localized on the right side of the neck. It included only neuroglial tissue. CONCLUSION: It is important to separate a teratoma with normal choroid plexus from a teratoma with choroid plexus tumor. Pathologists need to be aware of this entity in the distinction from other papillary neoplasms that may be primary or metastatic.

Multiple Sclerosis and the Choroid Plexus: Emerging Concepts of Disease Immunopathophysiology.

BACKGROUND: The coexistence of multiple sclerosis and intracranial neoplasms is very rare, and whether this occurrence can be explained by a causal relationship or by coincidence remains a matter of debate. Possible roles of the choroid plexus as a site of tumor cell invasion and lymphocyte infiltration into the central nervous system have been hypothesized in recent studies. METHODS: We describe a 13-year-old boy with concurrent multiple sclerosis and choroid plexus papilloma, then review the published literature with a focus on the pathophysiologic mechanisms of neuroinflammation in multiple sclerosis and the potential role of the choroid plexus in this process. RESULTS: A growing body of evidence suggests that both physical and functional dysregulation of the choroid plexus may be a common mechanism underlying the pathophysiology of central nervous system inflammation. CONCLUSIONS: In multiple sclerosis, the choroid plexus could act as a gateway for lymphocyte entry from the peripheral blood into the central nervous system at its earlier stages. However, future studies are needed to identify whether structural alterations of the choroid plexus play a role in the pathophysiology of multiple sclerosis and to provide suitable models to determine their consequences.

DNA methylation signature is prognostic of choroid plexus tumor aggressiveness.

BACKGROUND: Histological grading of choroid plexus tumors (CPTs) remains the best prognostic tool to distinguish between aggressive choroid plexus carcinoma (CPC) and the more benign choroid plexus papilloma (CPP) or atypical choroid plexus papilloma (aCPP); however, these distinctions can be challenging. Standard treatment of CPC is very aggressive and often leads to severe damage to the young child's brain. Therefore, it is crucial to distinguish between CPC and less aggressive entities (CPP or aCPP) to avoid unnecessary exposure of the young patient to neurotoxic therapy. To better stratify CPTs, we utilized DNA methylation (DNAm) to identify prognostic epigenetic biomarkers for CPCs. METHODS: We obtained DNA methylation profiles of 34 CPTs using the HumanMethylation450 BeadChip from Illumina, and the data was analyzed using the Illumina Genome Studio analysis software. Validation of differentially methylated CpG sites chosen as biomarkers was performed using pyrosequencing analysis on additional 22 CPTs. Sensitivity testing of the CPC DNAm signature was performed on a replication cohort of 61 CPT tumors obtained from Neuropathology, University Hospital Münster, Germany. RESULTS: Generated genome-wide DNAm profiles of CPTs showed significant differences in DNAm between CPCs and the CPPs or aCPPs. The prediction of clinical outcome could be improved by combining the DNAm profile with the mutational status of TP53. CPCs with homozygous TP53 mutations clustered as a group separate from those carrying a heterozygous TP53 mutation or CPCs with wild type TP53 (TP53-wt) and showed the worst survival outcome. Specific DNAm signatures for CPCs revealed AK1, PER2, and PLSCR4 as potential biomarkers for CPC that can be used to improve molecular stratification for diagnosis and treatment. CONCLUSIONS: We demonstrate that combining specific DNAm signature for CPCs with histological approaches better differentiate aggressive tumors from those that are not life threatening. These findings have important implications for future prognostic risk prediction in clinical disease management.

Histogram Analysis Parameters ADC for Distinguishing Ventricular Neoplasms of Ependymoma, Choroid Plexus Papilloma, and Central Neurocytoma.

BACKGROUND To determine if histograms of ADC can be used to differentiate ventricular ependymomas, choroid plexus papillomas (CPPs), and central neurocytomas (CNCs). MATERIAL AND METHODS We retrospectively reviewed records from 185 patients from 1 January 2014 to 1 November 2018. We finally included a total of 60 patients: 36 (60.00%) had histologically confirmed ependymomas, 10 (16.67%) had CPPs, and 14 (23.33%) had CNCs, as determined by routine MRI scanning at 3.0T. The ADC histogram features were derived and then compared by Kruskal-Wallis test (they were not normally distributed). Bonferroni test was used to compare the 2 groups and then we determined the ROC. RESULTS Ependymomas had significantly higher mean, perc.01%, perc.10%, perc.50%, perc.90%, and perc.99% than CNCs. Ependymomas had significantly lower skewness than CNCs. Histogram metrics derived from mean, perc.01%, perc.10%, perc.50%, and perc.90% were significantly lower in the CNCs group than in the CPPs group. CPPs showed significantly lower skewness than CNCs. A threshold value of 86.50 for perc.50% to predict ependymomas from CNCs was estimated (AUC=0.97, sensitivity=97.20%, specificity=85.70%). Optimal diagnostic performance to predict CPPs from CNCs (AUC=0.96, sensitivity=100.00%, specificity=85.70%) was obtained when setting Perc.50%=84.00 as the threshold value. CONCLUSIONS The ADC histogram analysis may help to discriminate ependymomas, CPPs, and CNCs.

Immunohistochemical Analysis of Cerebral Intraparenchymal Choroid Plexus Tumor: Case Report.

BACKGROUND: It is very rare for a choroid plexus tumor to occur intraparenchymally in the absence of a relation to the choroid plexus. CLINICAL PRESENTATION: A case of cerebral intraparenchymal choroid plexus tumor in a 30-year-old woman presenting with left hemiparesis is described. Brain magnetic resonance imaging depicted a large cystic mass in the right frontal lobe. Tumor resection was performed by right frontal craniotomy. No connection with the choroid plexus was observed during the operation. Histologically, the tumor exhibited a glandular structure with a papillary pattern suggesting a neoplasm of epithelial origin. Immunohistochemical analyses revealed the tumor as an atypical choroid plexus papilloma. CONCLUSION: Immunohistochemical findings, especially regarding Kir7.1, are very important for the differential diagnosis of cerebral intraparenchymal choroid plexus tumors from metastatic tumors. The present case reveals that an atypical choroid plexus papilloma can occur intraparenchymally without an association with the choroid plexus. Intraparenchymal atypical choroid plexus papillomas may have previously been diagnosed incorrectly as metastatic adenocarcinomas of unknown origin.

Metachronous Type I pleuropulmonary blastoma and atypical choroid plexus papilloma in a young child.

Pleuropulmonary blastoma (PPB) is a rare childhood tumor, often associated with germline DICER1 mutations and a risk for development of other benign and malignant tumors, a constellation termed DICER1 syndrome. A 1-year-old male was diagnosed with Type I PPB and screened regularly thereafter for detection of intrathoracic and intraabdominal disease. Ten months after diagnosis of PPB, he presented with headaches and vomiting. He was diagnosed with atypical choroid plexus papilloma, a lesion not previously reported with PPB. The presence of central nervous system symptoms in patients with PPB or a phenotype suggestive of DICER1 syndrome should prompt early intracranial imaging.

Choroid plexus papilloma in a beluga whale (Delphinapterus leucas).

We report herein a choroid plexus papilloma in a beluga whale (Delphinapterus leucas). This case was positive for choroid plexus tumor marker Kir7.1 on immunohistochemistry. These results and the high conservation of Kir7.1 across species at the amino acid sequence level strongly suggest that antibodies directed against Kir7.1 not only can be employed for the diagnosis of choroid plexus tumors in cetaceans, but are also likely to be diagnostically useful in other animal species.