Clinical Neuropathology最新文献

Endolymphatic sac tumor (ELST) is a rare disease that originates from the endolymphatic sac system of the inner ear. Being a low-grade malignant tumor, ELST has a mild morphology and is characterized by a slow but aggressive growth. Most clinicians and pathologists are unfamiliar with this disease. ELST can be misdiagnosed as metastatic renal cancer because of the similarity in morphology and expression of nephrogenic markers such as PAX8. The presented case of a 27-year-old man revealed that observing the characteristic location and confirming the absence of renal neoplasm to rule out the possibility of metastasis are critical for obtaining an accurate final diagnosis.

Atypical teratoid/rhabdoid tumor (AT/RT) is a highly malignant tumor of the central nervous system characterized by biallelic inactivation of SWI/SNF chromatin remodeling complex members SMARCB1/INI1 or (rarely) SMARCA4/BRG1. Most high-grade central nervous system lesions showing loss of nuclear SMARCB1 or SMARCA4 protein expression can indeed be categorized as AT/RT. However, some high-grade lesions have been identified, whose clinical and/or molecular features justify separation from AT/RT. Furthermore, other recently described tumor types such as desmoplastic myxoid tumor, SMARCB1-mutant, and low-grade diffusely infiltrative tumor, SMARCB1-mutant, may even manifest as low-grade lesions. Here, we review recent developments in the definition of the molecular landscape of AT/RT and give an update on other rare high- and low-grade SWI/SNF-deficient central nervous system tumors.

Objective: This research aims to examine the expression of carbonic anhydrase IX (CAIX) protein in hemangioblastoma of the central nervous system and its potential application in pathological diagnosis and differential diagnosis.

Materials and methods: Immunohistochemistry was used to identify the expression of CAIX and the α-inhibin protein. The sensitivity and specificity of CAIX and α-inhibin for identifying hemangioblastoma of the central nervous system were compared. In addition, 86 patients with meningiomas were gathered to detect CAIX protein expression. Hemangioblastoma and angiomatous, microcystic the two subtypes of meningiomas, were compared for CAIX and EMA protein expression.

Results: In hemangioblastoma, there were significant differences in the median positive percentage and staining intensity of CAIX and α-inhibin (p < 0.05). There was no discernible difference in the expression of the CAIX protein between sporadic hemangioblastoma of the central nervous system and those linked to von Hippel‒Lindau disease. In comparison to angiomatous and microcystic meningiomas, the positive rate of CAIX in hemangioblastomas was substantially greater (p < 0.001). The expression of EMA in microcystic meningioma (6/6) and angiomatous meningioma (17/17) was significantly different from hemangioblastoma (0/30) (p < 0.0001).

Conclusion: Hemangioblastoma might be diagnosed with high specificity and sensitivity through CAIX immunohistochemistry. The combination of CAIX with EMA is useful for the diagnosis and differential diagnosis of hemangioblastoma.

Thyroid transcription factor-1 (TTF-1) is a nuclear protein primarily recognized for its role in the development and differentiation of thyroid, lung, and certain diencephalic tissues. Although well-established as an immunohistochemical marker in thyroid and lung cancers, recent studies have explored its expression and diagnostic value in primary central nervous system (CNS) tumors. This systematic review aims to consolidate current knowledge on TTF-1 immunohistochemistry in primary CNS tumors, assessing its prevalence, diagnostic utility, and clinical implications. The review encompasses various CNS tumor types, including subependymal giant cell astrocytoma, chordoid glioma, pituicytoma, ependymomas, astrocytomas, glioblastomas, medulloblastomas, and choroid plexus tumors, highlighting the potential role of TTF-1 in differentiating these neoplasms from other CNS and metastatic tumors. By synthesizing findings from multiple studies, this review underscores the diagnostic value of TTF-1 in the neuropathological evaluation of CNS tumors and suggests directions for future research to refine its clinical application.

Background: A 71-year-old man presented with a history of headaches, blurred vision, diplopia, and right-sided ptosis. Magnetic resonance imaging (MRI) of the head revealed a 2.5 cm pituitary fossa lesion distorting the optic chiasm, with cavernous sinus invasion and frontal, temporal, and parieto-occipital lesions. Computed tomography (CT) found a retrosternal thyroid goiter. Biopsy of the occipital lobe lesion revealed metastatic papillary adenocarcinoma. Ultrasound-guided fine needle aspiration of the goiter and abnormal lymph nodes revealed Thy5. The patient underwent endoscopic transsphenoidal resection of the pituitary tumor, confirming papillary carcinoma of the thyroid. We sought to understand the clinico-radiological and histopathological features, treatment strategies, and outcomes of patients with thyroid cancer metastasis to the pituitary fossa.

Materials and methods: A date- and language-unrestricted literature search was performed across the MEDLINE, Embase, and Scopus databases using keywords relating to metastasis, the pituitary and thyroid glands, and the brain. Citations reporting patients with thyroid metastasis to the pituitary fossa were included. A proforma was used to extract and store data from the included citations.

Results: After deduplication, 2,833 citations were screened for eligibility, and 49 citations were included in the analysis.

Conclusion: We present a rare case illustration and comprehensive literature review of patients with thyroid cancer metastasis to the pituitary fossa.

Background: Chordoid glioma is a rare well-circumscribed glial neoplasm arising in adults and predominantly affects females. Tanycytes of the third ventricle have been proposed as the cell of origin owing to its location. It is characterized by chordoid features with myxoid and inflammatory stroma and recurrent PRKCA p.D463H missense mutation.

Case report: We present two cases (30-year-old female and 45-year-old male) with similar complaints of behavioral change and headache. Midline suprasellar homogeneously enhancing mass was seen on contrast-enhanced magnetic resonance imaging. Histopathology and immunohistochemistry was characteristic of chordoid glioma with cords and clusters of epithelioid cells arranged in a solid pattern. There were variable amounts of myxoid stroma and lymphoplasmacytic infiltrate. No mitosis, necrosis, or brain invasion was noted. The cells expressed strong diffuse positivity for glial fibrillary acid protein (GFAP) and weak nuclear thyroid transcription factor (TTF-1). Epithelial membrane antigen (EMA)and brachyury were negative. Subsequently, the lady underwent gross total excision and died soon after the operation. The male patient received radiotherapy and is currently doing well after 6 months of follow-up.

Conclusion: The rare occurrence as well as the radiological and morphological overlaps in chordoid gliomas make them a true masquerader. Combination of GFAP and TTF-1 in the immunohistochemical panel can be useful in differential diagnosis. Mainstay of treatment is complete surgical excision, with adjuvant radiotherapy becoming increasingly important.

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare distinctive neoplasm of infants with rapid expansile growth and a high rate of recurrence. Most commonly, the lesion affects the maxilla followed by the skull and orbit. One such case was diagnosed in a 5-month-old boy who presented with rapidly enlarged swelling over the back of the skull. Surgical excision was done. Typical histological features and immunohistochemical studies confirmed the diagnosis.

Two of the rarest radiation-induced adverse effects are focal neuronal gigantism (FNG) and SMART syndrome (stroke-like migraine attacks after radiation therapy). Both conditions develop years, and sometimes decades, after receipt of therapeutic radiation to the brain. To date, there are only 3 previously reported cases of FNG, all of which describe cortical thickening, enlarged "hypertrophic" neurons, and neuronal cytological changes. No detailed studies exist of histological features of SMART or the comparison between FNG and SMART. In this study, we contrast histological and neuroimaging features of 3 FNG vs. 4 SMART cases, the latter diagnosed by a neuroradiologist, neurooncologist, and/or neurosurgeon. We confirm the cortical thickening, dyslamination, neuronal cytomegaly, and gliosis in FNG vs. cortical architectural preservation and normal neuronal cytology in SMART, although both showed gliosis, scattered neurons with cytoplasmic accumulation of tau and neurofibrillary protein and variable co-existence of other radiation-induced lesions. Both conditions lacked significant inflammation or consistent small vessel hyalinization throughout the entire resection specimen. The absence of pathognomonic histologic alterations in SMART cases suggests underlying vascular dysregulation. Despite differing histology, some overlap may exist in neuroimaging features. Molecular assessment conducted in 2 cases of FNG was negative for significant alterations including in the MAPK pathway.

The Brain Tumor Epidemiology Consortium (BTEC) is an international organization with membership of individuals from the scientific community with interests related to brain tumor epidemiology including surveillance, classification, methodology, etiology, and factors associated with morbidity and mortality. The 2023 annual BTEC meeting entitled "Impact of Environment on Pediatric and Adult Brain Tumors" was held in Lexington, KY, USA on May 22 - 24, 2023. The meeting gathered scientists from the United States, Canada, Australia, and Europe and included four keynote sessions covering genomic, epigenomic, and metabolomic considerations in brain tumor epidemiology, cancer clusters, environmental risk factors, and new approaches to cancer investigation. The meeting also included three abstract sessions and a brainstorming session. A summary of the meeting content is included in this report.