A Primary Pigmented Choroid Plexus Papilloma Located Within the Sella Turcica: Case Report and Literature Review

Metastatic choroid plexus papilloma presenting as a sellar mass: A case report and literature review

Background

Choroid plexus papillomas (CPPs) are rare neoplasms arising from choroid plexus epithelium representing <1% of all intracranial tumors. Symptoms vary based on location and regional mass effect; however, hydrocephalus is common due to cerebrospinal fluid flow obstruction and/or overproduction. Distant site metastasis or de novo formation in extraventricular sites is rare.

Case Description

A 57-year-old female with a history of a 4th ventricular CPP status post resection in 2004 and 2018 with subsequent gamma knife therapy in 2019 presented with increased thirst and urination. Since her initial surgery, she has experienced significant gait imbalance, diplopia, dysphagia, and right-sided hemiparesis and hemisensory loss. Magnetic resonance imaging revealed a new 1.5 × 1.8 cm suprasellar lesion. She underwent a left supraorbital craniotomy for tumor resection, with pathology revealing metastatic World Health Organization grade II CPP.

Conclusion

Extraventricular manifestation of CPP is rare. De novo or metastatic involvement of the sella has seldom been reported. Treatment should target gross total surgical resection. Adjuvant chemotherapy and radiation may be useful in higher-grade lesions.

A rare trifocal presentation of a choroid plexus papilloma: Case report and review of the literature

Introduction

CPP's present as slow-growing intraventricular neoplasms arising from epithelium of choroid plexus. They account for approximately 0.5-4% of intracranial neoplasms in adults and children, respectively. A trifocal presentation is exceedingly rare.

Research question

We describe the case of a trifocal presentation of a CPP and explored the importance of genetic analyses.

Material and methods

We present the case of an 18-year old adolescent who was treated for a fourth ventricular and suprasellar neoplasm. Brain MRI revealed an intraventricular lesion in the fourth ventricle, as well as a suprasellar lesion and a lesion located in the left internal auditory meatus. An adult-subtype CPP (WHO grade 1) was confirmed by means of histological and genetic analyses in the first two regions.

Results

Optimal treatment strategy remains controversial, although it is accepted that surgical resection alone remains the gold standard, whereas chemoradiotherapy is reserved for specific cases. There are only a few articles reporting on a multifocal presentation or the coexistence of synchronous histologically different primary brain neoplasms. Reports on genetic examination are scarce.

Discussion and conclusion

CPP's should be included in the differential diagnosis of posterior fossa tumors, both in children and adults. Genetic analyses (TP53/TERT mutations) should be considered, since they entail important diagnostic, prognostic and therapeutic implications. When a TERT mutation is present, adjuvant radiotherapy should be used with caution, since it plays a role in tumorigenesis, even when GTR could not be achieved. There is an association between TERT methylation status and malignant transformation, indicating that these patients should be followed more closely.

Primary papillary epithelial tumour of the sella: expanding the spectrum of TTF-1-positive sellar lesions

AIM

To describe four novel primary epithelial tumours of the sella with papillary architecture and Thyroid Transcription Factor 1 (TTF-1) expression.

METHODS

Paraffin-embedded tissue from the four cases and recurrence of patient 1 was investigated with haematoxylin-eosin, special histochemical stains, immunohistochemistry with a broad panel of antibodies and next-generation sequencing. The ultrastructure of one tumour was studied in tissue retrieved from paraffin.

RESULTS

The lesions occurred in three females aged 20, 26 and 42 years and a male aged 49 years. They presented with signs and symptoms secondary to pituitary stalk compression. Preoperative neuroimaging documented mixed solid and cystic, enhancing sellar masses with suprasellar extension. Histologically, the tumours showed thin papillae lined by a single layer of cytokeratin and TTF-1-positive cuboidal and cylindrical cells with mildly atypical nucleus. Next-generation sequencing performed in three cases did not identify any mutations. The main differential diagnosis included metastasis from lung or thyroid carcinoma, extraventricular choroid plexus papilloma and sellar ependymoma.

CONCLUSION

We suggest the descriptive term of primary papillary epithelial tumour of the sella (PPETS) for this entity and propose that it could represent the intracranial equivalent of thyroid-like low-grade nasopharyngeal papillary adenocarcinoma. The cell of origin of PPETS remains undetermined although the intense and ubiquitous expression of TTF-1 may suggest a derivation from the infundibulum or ventricular recess. Our study expands the spectrum of sellar TTF-1-positive tumour and challenges the view that they all derive from pituicytes.

Pigmented primary epithelial tumor of the sella: A report of an intriguing case

This is a report of an uncommon primary pigmented papillary epithelial tumor of the sella in a 38-year-old man, who presented with clinicoradiological features of pituitary adenoma. Histologically, the tumor showed features reminiscent of choroid plexus papilloma, that is, conspicuous papillary epithelial morphology with presence of intacytoplasmic melanin and no mitotic activity. Immunohistochemically, the tumor was positive for pancytokeratin (AE1/AE3), S-100 protein and CD56, while it was negative for glial fibrillary acid protein, thyroid transcription factor-1, epithelial membrane antigen, other cytokeratins and pituitary hormones. These findings were not typical of any WHO-defined entity and is thus best regarded as a pigmented papillary epithelial tumor of sella of uncertain histogenesis. The present case is a valuable addition to the spectrum of primary pigmented papillary epithelial tumors originating at an unusual location.

Primary Choroid Plexus Papilloma over Sellar Region Mimicking with Craniopharyngioma: A Case Report and Literature Review

Choroid plexus papillomas (CPPs) are slow-growing and benign tumors, representing less than 1% of all intracranial neoplasms. They are predominantly located in the lateral ventricles in children, and in the fourth ventricle in adults. Primary CPP over sellar regions is extremely rare. There was previously only one case reported in men.

We report the case of a 43-year-old male who initially presented with bilateral temporal hemiapnosia. A brain magnetic resonance imaging (MRI) revealed heterogenous enhanced mass lesion with cyst component compressing upward onto the optic chiasm. A craniopharyngioma was initially suspected. Further endoscopic trans-sphenoidal surgery (ETS) was performed for total tumor resection. After surgery, the patient had visual field improved without tumor recurrence on post-operative MRI in clinical follow-up. Histopathological examination of the lesion confirmed the diagnosis of CPP, with fibrovascular cores covered by a single layer of cuboidal to columnar epithelial cells.

CPP is a rare tumor without specific clinical patterns or imaging findings. Therefore, pre-operative differential diagnosis is difficult for this kind of tumor with complete separation from ventricular system. An ETS for total tumor resection provided effective treatment.