Psammomatous choroid plexus papilloma

An unexpected sudden death due to a choroid plexus papilloma: an autopsy case report

Background

Choroid plexus papillomas (CPPs) are histopathologically benign and rare central nervous system tumors. These tumors remain more frequent in children than adults. It is infrequent for these tumors to cause a sudden unexpected death. We aim in this case to discuss the unusual and fatal presentation of choroid plexus papilloma and the mechanism of death.

Case presentation

we report the case of a 61-year-old man with no medical history, diagnosed at autopsy with a previously unknown CPP. Initial complaints were chronic headache occurring in the last month and acute chest pain for two days. The forensic autopsy including the histopathologic examination showed a tumoral mass of the choroid plexus in the fourth ventricle diagnosed as a psammomatous CPP. The cause of death in this case was attributed to a massive cerebral edema caused by the tumoral mass.

Conclusions

Through this case report, we stress the importance of an early and a vigorous investigation of every headache and an early detection of this tumor and we highlight as well the role of the post mortem examination to detect such a fatal complication.

Imaging findings of extraventricular choroid plexus papillomas: A study of 10 cases

Extraventricular choroid plexus papillomas (CPPs) are rare. In this study, we reveal the imaging findings of CPPs located in extraventricular sites. The imaging findings of 11 masses [10 masses on magnetic resonance imaging (MRI) and one mass on computed tomography (CT)] of extraventricular CPP in 10 patients were retrospectively observed. The mass site, size, contour, signal intensity, cystic or solid appearance, calcification, capsules, degree and pattern of enhancement, and hydrocephalus were evaluated based on CT or MRI. The misdiagnosis rate of CPPs in extraventricular sites was 80.0% (8/10). Solitary masses and multiple masses were observed in nine patients (90.0%, 9/10) and one patient (10%, 1/10), respectively. In addition to the typical imaging findings [a lobulated, cauliflower-like or mulberry-like mass that is homogeneous isointense or slightly hypointense on T1-weighted imaging (T1WI) and heterogeneous isointense or slightly hyperintense on T2WI], four masses had round or oval contours and three had cystic components; abnormal signal intensity (mixed hyperintense signals on T1WI and T2WI or slightly hyperintense signals on T1WI or hypo-/hyperintense on T2WI) and low or no enhancements were observed in three and six masses, respectively; absence of hydrocephalus and mild or local hydrocephalus were each observed in four subjects, respectively. Hemorrhage and psammomatous bodies and/or calcification were observed in four and three masses, respectively. In conclusion, in addition to the typical imaging findings, atypical imaging findings, including atypical contours, abnormal signal intensity, low enhancement and absence of hydrocephalus were also observed in extraventricular CPPs.

Immunohistochemical and morphometric analysis of immunoglobulin light-chain immunoreactive amyloid in psammoma bodies of the human choroid plexus

The aim of this research was to establish the presence of amyloid and to quantify immunohistochemical reactions of kappa and lambda light chains of psammoma bodies of the choroid plexus. Choroid plexus tissue obtained from 14 right lateral ventricles postmortem was processed histologically and stained with Congo red, thioflavin T, and monoclonal antibodies for kappa and lambda light chains. Morphological analysis was performed with a light microscope at lens magnifications of 4×, 10×, 20×, 25×, and 40×. The morphometric characteristics of psammoma bodies that were kappa and lambda positive and negative were analyzed with ImageJ. Histological analysis showed that the psammoma bodies, stromal blood vessel walls, and some epithelial cells reacted positively with Congo red and thioflavin T. Psammoma bodies were predominantly positive for lambda light chains. Lambda positivity was detected inside some stromal blood vessels, which pointed to a probable systemic origin for these light chains. Morphometric analysis showed that the mean optical densities of lambda- and kappa-positive psammoma bodies were significantly higher than those that gave a negative reaction. The percentage of lambda-positive psammoma bodies was significantly higher than the percentage of lambda-negative psammoma bodies in 80% of the cases, while the reaction with kappa light chains was negative in the majority of the cases. Linear regression analysis showed a significant increase in the percentage of lambda-positive psammoma bodies and their mean optical density with age. Finally, it can be concluded that the positive reaction of psammoma bodies in the choroid plexus with respect to amyloid and lambda light chains may point to the presence of light-chain amyloid in their structures.

Ossified choroid plexus papilloma of the fourth ventricle: elucidation of the mechanism of osteogenesis in benign brain tumors

True ossification within benign brain tumors is rare, and the molecular mechanism for this process is poorly understood. The authors report a case of ossified choroid plexus papilloma (CPP) and analyze it to help elucidate the underlying molecular basis of osteogenesis in benign brain tumors. A 21-year-old man presented with headache and depression that progressed over years. Computed tomography, MRI, and angiography demonstrated a large heavily calcified fourth ventricular tumor with a vascular blush and no hydrocephalus. The tumor was resected and was found to be an ossified CPP. Immunohistochemical staining for VEGF, Sox2, BMP-2, osterix, osteopontin, and osteocalcin was performed in an attempt to elucidate the mechanism of bone formation. The tumor was extensively ossified with mature bone trabeculae. Immunostaining for VEGF was positive. Additional staining showed the presence of osteocalcin in this ossified tumor but not in samples of nonossified CPPs collected from other patients. Staining for osterix and osteopontin was equivocally positive in the ossified CPP but also in the nonossified CPPs examined. The presence of osteocalcin in the ossified CPP demonstrates that there is true bone formation rather than simple calcification. Its appearance within cells around the trabeculae suggests the presence of osteoblasts. The presence of osterix suggests that a pluripotent cell, or one that is already partially differentiated, may be differentiated into an osteoblast through this pathway. This represents the first systematic immunohistochemical analysis of osteogenesis within choroid plexus tumors.

Choroid plexus papillomas: advances in molecular biology and understanding of tumorigenesis

Choroid plexus papillomas are rare, benign tumors originating from the choroid plexus. Although generally found within the ventricular system, they can arise ectopically in the brain parenchyma or disseminate throughout the neuraxis. We sought to review recent advances in our understanding of the molecular biology and oncogenic pathways associated with this disease. A comprehensive PubMed literature review was conducted to identify manuscripts discussing the clinical, molecular, and genetic features of choroid plexus papillomas. Articles concerning diagnosis, treatment, and long-term patient outcomes were also reviewed. The introduction of atypical choroid plexus papilloma as a distinct entity has increased the need for accurate histopathologic diagnosis. Advances in immunohistochemical staining have improved our ability to differentiate choroid plexus papillomas from other intracranial tumors or metastatic lesions using combinations of key markers and mitotic indices. Recent findings have implicated Notch3 signaling, the transcription factor TWIST1, platelet-derived growth factor receptor, and the tumor necrosis factor-related apoptosis-inducing ligand pathway in choroid plexus papilloma tumorigenesis. A combination of commonly occurring chromosomal duplications and deletions has also been identified. Surgical resection remains the standard of care, although chemotherapy and radiotherapy may be considered for recurrent or metastatic lesions. While generally considered benign, these tumors possess a complex biology that sheds insight into other choroid plexus tumors, particularly malignant choroid plexus carcinomas. Improving our understanding of the molecular biology, genetics, and oncogenic pathways associated with this tumor will allow for the development of targeted therapies and improved outcomes for patients with this disease.

Clinicopathologic and immunohistochemical study of choroid plexus tumors: single-institution experience in Mexican population

In recent years, few studies have specifically focused on only histological features in choroid plexus tumors. We retrospectively reviewed the clinicopathologic and histological features in 37 patients with choroid plexus tumors and correlated these with glial fibrillary acidic protein (GFAP) expression and proliferation cell nuclear antigen (PCNA), p53, p21, and Rb labeling indexes, with special attention to tumor recurrence/regrowth. The study included 24 choroid plexus papillomas (CPPs), 4 atypical choroid plexus papillomas (ACPPs), and 9 choroid plexus carcinomas (CPCs). Patient age ranged from 15 to 70 years (mean 44 years). Most of the choroid plexus tumors were located in the IV ventricle. Recurrence was observed in 21 (52%) cases, 14 of which were CPP and 7 of which were CPC (P = 0.032). Histologic findings included major necrosis, fibrosis and psammoma bodies, amyloid deposits, inflammation, and thick vessels in recurrent tumors. The PCNA labeling index was 52.04 + or - 13.92 in CPPs, 76.50 + or - 17 in ACPPs, and 95.22 + or - 21.34 in CPCs (P = 0.009), and 67.43 + or - 28 in recurrent tumors. Similar values were found for p53, p21, and Rb. Furthermore, we observed that these presented more histological changes, adding, than nonrecurrent tumors, as well as a higher proliferation index of cell-cycle markers, and these were dependent predictor factors of survival. Recurrent tumors showed a different biological behavior than nonrecurrent tumors, but histological observations showed no mitotic features in order to consider them as grade II.

Atypical choroid plexus papilloma in an adult

We present an extremely rare case of the atypical choroid plexus papilloma in an adult which developed at the trigone of right lateral ventricle. A 62-year-old woman presented with the history of intermittent and gradually progressive headache and left side hemiparesis for 6 months. The brain magnetic resonance image showed highly enhanced and well demarcated mass at the trigone of lateral ventricle attached to the choroid plexus. Gross total resection was performed by transcortical approach via the middle temporal gyrus. The tumor was diagnosed as an atypical choroid plexus papilloma. She had no neurologic deficit after the surgery. We report a case of atypical choroid plexus papilloma in adult and introduce newly classified pathologic characteristics of this tumor.