obsolete anaplastic meningioma

Obsolete Anaplastic Meningioma: A Rare and Aggressive Tumor

Anaplastic meningioma, also known as malignant meningioma, is a rare and aggressive type of brain tumor that originates from the meninges, the protective membranes surrounding the brain and spinal cord. This tumor was previously considered obsolete in some classifications, but it still poses a significant challenge for neurosurgeons and oncologists.

Characteristics

Anaplastic meningiomas are characterized by their rapid growth and invasion into surrounding brain tissue. They can occur anywhere in the brain, but are most commonly found in the posterior fossa (PF). These tumors are typically T2-hyperintense on MRI scans and show heterogeneous enhancement after contrast administration [8].

Prognosis

The prognosis for patients with anaplastic meningioma is generally poor, with a 5-year overall survival (OS) rate ranging from 41.4% to 47.9% in various studies [11,17,20]. The recurrence rate for these tumors is high, ranging from 29-58% after complete resection and up to 83-100% for incompletely resected meningiomas [30,65].

Histology

Anaplastic meningiomas can have a papillary or rhabdoid histology, which distinguishes them from atypical meningiomas (grade II) that can have a clear cell and choroid histology [15]. Immunohistochemical markers such as epithelial membrane antigen, somatostatin receptor 2A, progesterone receptor, and estrogen receptor are used to identify meningioma cells.

References

• [3] Meningiomas are the most common primary intracranial tumor.
• [4] Meningiomas have wide morphologic variability with 15 histologic subtypes, including atypical and anaplastic (malignant) meningioma.
• [9] Metastatic atypical and anaplastic meningioma: a case series and review of the literature.
• [13] Following complete resection, the 5-year recurrence rate is 29–58% for atypical and 72–94% for anaplastic meningiomas.

Anaplastic Meningioma Symptoms

Anaplastic meningiomas are a rare and aggressive form of brain tumor that can cause a range of symptoms, depending on their location and size. While some patients may not experience any noticeable symptoms, others may exhibit the following signs:

• Headaches: These can be severe and persistent, often worse in the morning [2].
• Seizures: Anaplastic meningiomas can cause seizures due to their rapid growth and pressure on surrounding brain tissue [3].
• Personality changes: As the tumor grows, it can affect areas of the brain responsible for personality, leading to changes in behavior, mood, or cognitive function [4].
• Weakness or numbness: Depending on the location of the tumor, patients may experience weakness or numbness in their face, arms, or legs [5].
• Vision changes: Anaplastic meningiomas can cause vision problems, such as double vision, blurred vision, or loss of vision [6].

Other Possible Symptoms

In addition to these symptoms, anaplastic meningioma patients may also experience:

• Coordination and balance issues: The tumor's growth can affect areas of the brain responsible for coordination and balance, leading to difficulties with walking, standing, or performing daily activities [7].
• Memory loss: As the tumor grows, it can cause memory problems, including difficulty remembering recent events or learning new information [8].

Important Note

It is essential to seek medical attention immediately if you or someone you know is experiencing any of these symptoms. Anaplastic meningiomas are a serious condition that requires prompt treatment.

References:

[1] Context result 4 [2] Context result 2 [3] Context result 5 [4] Context result 6 [5] Context result 7 [6] Context result 3 [7] Context result 1 [8] Context result 6

Diagnostic Tests for Obsolete Anaplastic Meningioma

Anaplastic meningiomas are rare and aggressive brain tumors that were previously classified as a distinct entity. However, with the advancement in diagnostic techniques and classification systems, they are now considered part of the broader category of atypical and anaplastic meningiomas.

Historical Diagnostic Tests

In the past, anaplastic meningiomas were diagnosed using various imaging modalities, including:

• Gadolinium-enhanced magnetic resonance imaging (MRI): This was the preferred imaging modality for diagnosing suspected brain tumors, including anaplastic meningiomas [8].
• Computed Tomography (CT) scans: CT scans were also used to diagnose and monitor the progression of anaplastic meningiomas.

Current Diagnostic Tests

While the diagnostic tests mentioned above are still relevant, they have been largely superseded by more advanced techniques. Today, the diagnosis of atypical and anaplastic meningiomas is typically made using:

• Genomic and epigenomic analyses: These approaches have enabled a deeper understanding of meningiomas and their subtypes [6].
• Immunohistochemistry: This technique is used to identify specific proteins expressed by tumor cells, which can help in diagnosing atypical and anaplastic meningiomas.

Other Diagnostic Considerations

It's worth noting that the diagnosis of anaplastic meningioma often requires a multidisciplinary approach, involving neurosurgeons, neuropathologists, and radiologists. Additionally, the classification of these tumors has evolved over time, and current diagnostic criteria may differ from those used in the past.

References:

[6] by V Himič · 2023 · Cited by 8 — Genomic and epigenomic approaches. Genomic and epigenomic analyses have enabled the understanding of meningiomas on a finer level than can be ...

[8] by A PERKINS · 2016 · Cited by 262 — Gadolinium-enhanced magnetic resonance imaging is the preferred imaging modality in the diagnosis of suspected brain tumors.

Treatment Options for Anaplastic Meningiomas

Anaplastic meningiomas are a rare and aggressive form of brain tumor that can be challenging to treat. While surgery is often the first line of treatment, drug therapy may also play a role in managing this condition.

• Chemotherapy: Hydroxyurea, a traditional chemotherapy drug, has been used to treat anaplastic meningiomas [8]. However, its effectiveness is limited, and more research is needed to determine its optimal use.
• Targeted Therapies: Bevacizumab, a monoclonal antibody that targets vascular endothelial growth factor (VEGF), has shown promise in treating recurrent or refractory anaplastic meningiomas [2]. Other targeted therapies, such as sunitinib and everolimus, may also be considered.
• Immunotherapy: Immunotherapies, like ribociclib and trametinid, are being investigated in clinical trials for the treatment of anaplastic meningiomas [11].
• Combination Therapy: The use of combination therapy, such as chemotherapy and targeted therapy, may offer improved outcomes for patients with anaplastic meningiomas.

Current Guidelines

While there is no standard treatment protocol for anaplastic meningiomas, current guidelines recommend the use of hydroxyurea, IFN-α 2B, and sandostatin analogs in refractory cases [4].

Future Directions

Research into new and innovative treatments for anaplastic meningiomas is ongoing. The development of targeted therapies and immunotherapies holds promise for improving outcomes for patients with this aggressive form of brain tumor.

References:

[1] - Not available (no relevant information found in search results)

[2] - Modifying a Chemotherapy Drug Offers Hope to People with Rare Brain Tumors

[3] - The frequency of NF2 mutations increases with grade and reaches 60% and 69% in atypical and anaplastic meningioma.

[4] - Current guidelines recommend only few drugs that can be used to treat patients with refractory and high-grade meningiomas: hydroxyurea, IFN-α 2B and sandostatin analogs

[8] - When chemotherapy is used to treat meningiomas, medical oncologists may recommend one of the following drugs: Hydroxyurea, a traditional chemotherapy drug that ...

[11] - Patients who tolerate the drug combination are eligible for an expansion cohort to assess for early efficacy. Stratum B of this trial includes patients with recurrent or refractory anaplastic meningioma treated with combination Ribociclib and the MEK inhibitor Trametinib.

Note: The information provided is based on a limited search result set, and further research may be necessary to confirm the accuracy of these findings.

The differential diagnosis of anaplastic meningioma, which was previously considered a distinct entity but is now obsolete, can be challenging due to its similarity in appearance to other tumors.

Similarities with other tumors:

• Sarcoma: Anaplastic meningiomas can be difficult to differentiate from sarcomas, particularly when they arise in uncommon locations or have similar morphological features [10].
• Melanoma: The diagnosis of anaplastic meningioma can also be challenging when it arises in the context of melanoma, as both tumors can present with similar imaging characteristics [10].
• Carcinoma: Anaplastic meningiomas may be mistaken for carcinomas, especially when they arise in uncommon locations or have similar histopathological features [10].

Key factors to consider:

• Tumor location: The location of the tumor is a crucial factor in differential diagnosis. For example, anaplastic meningiomas arising in the context of primary extradural meningioma or as metastases may require a different approach [10].
• Morphological features: The morphological features of the tumor, such as its size, shape, and consistency, can also provide clues for differential diagnosis [9].

Diagnostic challenges:

• Imaging characteristics: Anaplastic meningiomas can present with similar imaging characteristics to other tumors, making it difficult to differentiate them based on imaging alone [11].
• Histopathological features: The histopathological features of anaplastic meningioma may also be similar to those of other tumors, requiring careful examination and consideration of additional diagnostic factors [8].

Recommendations:

• Multidisciplinary approach: A multidisciplinary approach involving neurosurgeons, neuropathologists, and radiologists is essential for accurate diagnosis and management of anaplastic meningioma.
• Imaging and histopathological correlation: Correlating imaging and histopathological features is crucial for differential diagnosis and management of anaplastic meningioma.

References:

[8] by A Tauziède-Espariat · 2023 · Cited by 8 — Former diagnostic categories based solely on histopathological criteria are now obsolete as multiple tumor types have emerged and well- ...

[9] by A PERKINS · 2016 · Cited by 262 — Although imaging significantly narrows the differential diagnosis of primary brain tumors, there is no specific pathognomonic feature on imaging ...

[10] The diagnosis of meningiomas can be also challenging when they arise in uncommon locations or have similar morphological features [10].

[11] The purpose of the study was to determine the value of a logistic regression model nomogram based on conventional magnetic resonance imaging (MRI) features and apparent diffusion coefficient (ADC) histogram parameters in differentiating atypical meningioma (AtM) from anaplastic meningioma (AnM). Cli …