diffuse glioma, H3 G34 mutant

Diffuse Hemispheric Glioma, H3 G34-mutant: A Rare and Aggressive Brain Tumor

Diffuse hemispheric glioma, H3 G34-mutant (DHG H3G34) is a rare and aggressive type of brain tumor that affects the cerebral hemisphere. It is characterized by mutations in the H3F3A gene, which codes for the histone variant H3.3.

Key Features:

• Age: DHG H3G34 typically presents in adolescents and young adults, with a median age at diagnosis around 20 years [4].
• Grade: It is considered a high-grade glioma, similar to glioblastomas (GBMs) [7].
• Location: The tumor is located in the cerebral hemisphere, often presenting as an expansile, contrast-enhancing lesion on MRI imaging [2].
• Histology: Histologically, DHG H3G34 appears as a diffuse high-grade glioma with a primitive embryonal-like appearance [2].

Clinical Features:

• Malignancy: DHG H3G34 is considered a malignant tumor, with a dismal prognosis [7].
• Infiltration: The tumor is highly infiltrative, making complete resection challenging [14].
• IDH status: Unlike many other gliomas, DHG H3G34 is IDH-wildtype [3].

Prognosis:

• Survival: Unfortunately, the prognosis for patients with DHG H3G34 is poor, with limited survival data available [11].
• Factors impacting prognosis: Understanding factors that impact prognosis, such as resection extent and temozolomide use, is crucial for clinical advancements and patient care [14].

References:

[1] Context 10 [2] Context 2 [3] Context 3 [4] Context 4 [7] Context 7 [11] Context 11 [14] Context 14

Symptoms of Diffuse Hemispheric Glioma, H3 G34-mutant

Diffuse hemispheric gliomas, H3 G34-mutant (DHG) are aggressive brain tumors that can cause a range of symptoms. Some common signs and symptoms include:

• Increased intracranial pressure: This can lead to symptoms such as:
  • Headache [3]
  • Nausea [3]
  • Vomiting [3]
• Site-dependent neurological deficits: Depending on the location of the tumor, patients may experience:
  • Epileptic seizures [10]
  • Focal deficit (weakness or numbness in a specific area) [9][10]
  • Increased intracranial hypertension [10]

These symptoms can vary depending on the size and location of the tumor. It's essential to seek medical attention if you or someone you know is experiencing any of these symptoms.

References:

[3] - Symptoms related to increased intracranial pressure, such as headache, nausea and vomiting · May have site dependent neurological deficits ... [9] - by AV Nguyen · 2023 · Cited by 5 — A diagnosis of “diffuse hemispheric glioma, H3G34-mutant” (DHG) was delineated in the pediatric-type diffuse high-grade glioma category. These patients have a ... [10] - Feb 25, 2024 — Site dependent neurological symptoms including epileptic seizure, focal deficit, increased intracranial hypertension (headache, nausea and ...

Diagnostic Testing for Diffuse Glioma, H3 G34 Mutant

Diffuse gliomas are a type of brain cancer that can be challenging to diagnose. The H3 G34 mutation is a specific genetic alteration found in some cases of diffuse glioma.

• H3 G34 testing: This test is used to detect the presence of the H3 G34 mutation in tumor tissue. It is recommended for pediatric and young adult patients with IDH-wild-type (IDH-WT) diffuse gliomas, but not typically for older adults [2].
• Histone 3 (H3) K27M testing: This test is used to detect the presence of the H3 K27M mutation in tumor tissue. It is recommended for diffuse gliomas that involve the midline in the appropriate clinical and pathologic setting [12].
• Imaging studies: Imaging studies such as MRI are typically used to evaluate the extent of tumor spread and to guide biopsy procedures.
• Biopsy and histopathological examination: A biopsy is a procedure where a small sample of tissue is taken from the tumor for examination under a microscope. Histopathological examination involves examining the tumor tissue for specific features, including the presence of the H3 G34 mutation.

When would testing be most diagnostically useful?

The diagnostic value of H3 G34 testing in adults with diffuse glioma is still being studied. However, it has been suggested that testing may be most diagnostically useful when there are clinicopathological features suggestive of a high-grade tumor [1].

• Frequency and clinicopathological features: Studies have shown that the frequency and clinicopathological features of DHG-H3 G34 among adult nonmidline IDH-WT diffuse gliomas with grade 4 morphological features may be higher than previously thought [1].
• Age and prognosis: The median age at diagnosis in diffuse hemispheric gliomas, H3 G34-mutant is around 18-19 years. However, half of the patients are followed by adult neuro-oncologists, and the characteristics and outcome of adult diffuse hemispheric gliomas, H

Treatment Options for Diffuse Hemispheric Glioma (H3 G34-mutant)

Diffuse hemispheric glioma with a H3 G34 mutation is a type of brain cancer that requires prompt and effective treatment. While there are no specific treatments mentioned in the search results, we can infer some potential options based on related information.

• Surgery: Whenever possible, surgery should be considered as an initial treatment for pHGG (primary high-grade glioma), including H3 G34-mutant diffuse hemispheric glioma [10]. The goal of surgery is to remove the tumor and alleviate symptoms.
• Temozolomide chemotherapy: Temozolomide is a standard treatment at progression after surgery and radiotherapy for most patients with IDH-mutant gliomas, which may include H3 G34-mutant diffuse hemispheric glioma [6]. However, the effectiveness of temozolomide in older patients with MGMT promoter methylation can be beneficial [7].
• Immunotherapy: Peptide-pulsed dendritic cell vaccination in combination with immunotherapy (nivolumab and ipilimumab) has been tested in a phase I trial for the treatment of diffuse hemispheric glioma, including H3 G34-mutant cases [1]. However, more research is needed to confirm its efficacy.
• Neoantigen-targeted ppDC: Giving neoantigen-targeted ppDC may be safe, tolerable, and/or effective in treating patients with diffuse hemispheric glioma with a H3 G34 mutation [3] and [8].

It's essential to note that the most suitable treatment plan will depend on individual patient factors, such as tumor location, size, and clinical status. A comprehensive review of the clinical features that impact prognosis for patients with diffuse hemispheric glioma is available in the literature [4]. Consultation with a medical professional or a neuro-oncologist is recommended to determine the best course of treatment.

References: [1] - Context result 1 [3] - Context result 3 [6] - Context result 6 [7] - Context result 7 [8] - Context result 3 and 8 [10] - Context result 10

The differential diagnosis for diffuse hemispheric glioma, H3 G34-mutant includes other pediatric brain tumors that may present with similar clinical features.

• Other pediatric brain tumors to consider in the differential diagnosis include:
  • Medulloblastoma
  • Ependymoma
  • Craniopharyngioma
  • Astrocytoma

These tumors can have overlapping symptoms and imaging characteristics, making accurate diagnosis challenging. A comprehensive diagnostic workup, including histopathological examination, molecular analysis, and radiological evaluation, is essential to distinguish diffuse hemispheric glioma, H3 G34-mutant from other pediatric brain tumors.

According to [2], differential diagnosis includes the other pediatric- brain tumors that may present with similar clinical features.