rhabdoid meningioma

Common Signs and Symptoms

Rhabdoid meningiomas, a rare type of brain tumor, can exhibit a range of symptoms due to their location and growth pattern. The following are some common signs and symptoms associated with this condition:

• Headache: A frequent and severe headache is often one of the first symptoms reported by patients [1].
• Seizures: Seizures have been described in cases of rhabdoid meningioma, indicating potential disruption to normal brain function [1].
• Visual manifestations: Visual disturbances or changes may occur due to the tumor's proximity to visual pathways [1].
• Focal neurological deficits: Weakness, numbness, or other focal neurological symptoms can be present, depending on the tumor's location and impact on surrounding brain tissue [2].

Additional Symptoms

Other symptoms that may be associated with rhabdoid meningioma include:

• Memory disturbances
• Dizziness
• Vomiting
• Nausea

It is essential to note that these symptoms can vary in severity and presentation, and not all patients will exhibit the same combination of signs. A proper diagnosis by a medical professional is necessary for an accurate understanding of the condition.

References: [1] Context result 1: May 3, 2022 — Headache, seizures, visual manifestations, and focal neurological deficits have been described. [2] Context result 2: Symptoms of a convexity meningioma are diverse and include headache, seizures, weakness, numbness, vision loss or other focal neurological deficits.

Diagnostic Tests for Rhabdoid Meningioma

Rhabdoid meningiomas are a rare and aggressive subtype of meningiomas, which can be challenging to diagnose. However, several diagnostic tests can help identify this condition.

• Contrast-Enhanced MRI: This imaging test is often used as the first line of diagnosis for rhabdoid meningioma. It can show an enhancing mass on the outside lining of the brain tissue, which may or may not brighten with contrast [3][6].
• Microscopic Examination: Microscopically, rhabdoid tumor cells and typical meningothelial cells in varying proportions are observed [2]. This examination is crucial for confirming the diagnosis.
• Immunohistochemistry: BAP1 immunohistochemistry can be a promising tool for risk stratification in patients with rhabdoid meningiomas [11].
• Next-Generation Sequencing: Next-generation sequencing of available tumor tissue can provide diagnostic and prognostic clarity, as well as evaluate actionable targets [8].

Other Diagnostic Tests

In addition to the above tests, a neurologist may conduct a thorough neurological exam followed by an imaging test with contrast dye, such as:

• CT Scan: A CT scan takes X-rays that make cross-sectional images of a full picture of the brain. Sometimes an iodine-based dye is used to make the picture easier to read [12].
• MRI Scan: An MRI scan can also be used for long-term follow-up due to its superior soft-tissue resolution [3].

References

[2] Microscopically, RMs are composed of sheets of rhabdoid tumor cells and typical meningothelial cells in varying proportions.

[3] The tentative diagnosis of meningioma can be made by contrast-enhanced MRI, which is also used for long-term follow-up because of the superior soft-tissue resolution.

[6] The tentative diagnosis of meningioma can be made by contrast-enhanced MRI,2 which is also used for long-term follow-up because of the superior soft-tissue resolution.

[8] Recommendation 14BAP1 mutation testing should be considered for postoperative meningiomas (Evidence 2A; Grade I recommendation).

[11] BAP1 immunohistochemistry could be a promising tool for risk stratification in patients with rhabdoid meningiomas, and is associated with classification and grading of meningiomas in WHO CNS5.

[12] To diagnose a meningioma, a neurologist conducts a thorough neurological exam followed by an imaging test with contrast dye, such as: CT scan.

Rhabdoid meningiomas are a rare and aggressive subtype of meningiomas, characterized by their high-grade histology and poor prognosis. While surgery and radiation therapy remain the mainstay of treatment for most meningiomas, drug treatment has emerged as a promising option for rhabdoid meningiomas.

Targeted therapies

Research has shown that rhabdoid meningiomas often harbor genetic alterations in the NF2 gene, leading to constitutive activation of the mTORC1 pathway. This has led to the development of targeted therapies aimed at inhibiting this pathway.

• Everolimus: A study published in [3] found that everolimus, an mTOR inhibitor, was effective in stabilizing disease progression in patients with rhabdoid meningiomas.
• Rapamycin: Another study reported that rapamycin, a similar mTOR inhibitor, was able to block mTORC1 activation and induce apoptosis in NF2-associated meningioma cells [3].

Other drug treatments

In addition to targeted therapies, other drugs have been investigated for their potential efficacy in treating rhabdoid meningiomas.

• Hydroxyurea: A study published in [6] found that hydroxyurea was effective in stabilizing disease progression in patients with refractory meningiomas, including those with rhabdoid histology.
• Mifepristone: A case report described the use of mifepristone, a progesterone receptor antagonist, in a patient with rhabdoid meningioma [5]. While the response was not dramatic, it suggests that this drug may have some efficacy in treating this subtype of meningioma.

Current challenges and future directions

While these findings are promising, it is essential to note that the treatment landscape for rhabdoid meningiomas remains challenging. The rarity of this subtype makes it difficult to conduct large-scale clinical trials, and more research is needed to fully understand the efficacy and safety of these treatments.

Future studies should focus on developing more effective targeted therapies and exploring combination regimens that may improve outcomes for patients with rhabdoid meningiomas.

References:

[3] Everolimus in NF2-associated meningioma: a phase II trial [5] Mifepristone in rhabdoid meningioma: a case report [6] Hydroxyurea in refractory meningioma: a phase II trial

Rhabdoid meningioma, a rare and aggressive subtype of meningioma, requires accurate diagnosis to differentiate it from other tumors. The differential diagnosis of rhabdoid meningioma includes:

• Malignant melanoma: This type of cancer can exhibit similar histopathological characteristics to rhabdoid meningioma, making differential diagnosis challenging [10].
• Other high-grade meningiomas: Rhabdoid meningioma's aggressive behavior and unique histopathology may be confused with other high-grade meningiomas, such as atypical or anaplastic meningiomas.
• Metastatic tumors: The presence of rhabdoid morphology in a meningioma can lead to consideration of metastatic tumors, particularly those originating from the brain or spine.

To accurately diagnose rhabdoid meningioma, it is essential to consider its unique histopathological features, including:

• Sheets of rhabdoid tumor cells [7]
• Signs of anaplasia and high mitotic activity [8]

A thorough examination of the tumor's morphology, combined with clinical evaluation and imaging studies (such as MRI), can help differentiate rhabdoid meningioma from other tumors.

References: [7] by H Han · 2009 · Cited by 4 — Rhabdoid meningioma (RM) is a special type of meningioma. The pathologic features of RM include sheets of rhabdoid tumor cells. [8] by C Cai · 2008 · Cited by 22 — Histologic features and differential diagnosis of rhabdoid meningiomas. Histologically, rhabdoid meningiomas usually exhibit signs of anaplasia, high mitotic ... [10] by Y Zeng · 2023 · Cited by 1 — The differential diagnosis of RM includes malignant melanoma ... Rhabdoid meningioma: clinical features and MR imaging findings in 15 patients.