diffuse astrocytoma, MYB- or MYBL1-altered

Diffuse Astrocytoma, MYB- or MYBL1-Altered: A Rare and Pediatric-Type Glioma

Diffuse astrocytoma, MYB- or MYBL1-altered is a rare and low-grade type of glioma that primarily affects children. This tumor is characterized by genetic alterations in the MYB or MYBL1 genes.

Key Characteristics:

• Age: Typically arises in children, with median ages of 7.2 years for MYB-altered and 5.0 years for MYBL1-altered tumors [2].
• Grade: Low-grade glioma, which means it grows slowly and is less aggressive compared to higher-grade gliomas.
• Genetic Alterations: Involves mutations or alterations in the MYB or MYBL1 genes, which are distinct from other types of gliomas.

Additional Information:

• This tumor type is closely related to pediatric-type diffuse low-grade gliomas (pLGG) [3].
• Diffuse astrocytoma, MYB- or MYBL1-altered is a rare and very rare condition, respectively [4][8].

References:

[2] Sep 23, 2024 — Typically arises in children (median age is 7.2 years for MYB altered and 5.0 years for MYBL1 altered) ... [3] by DC Moreira · 2024 · Cited by 4 — Pediatric-type diffuse low-grade gliomas (pLGG) harboring recurrent genetic alterations involving MYB or MYBL1 are closely related tumors. [4] Apr 4, 2022 — Diffuse astrocytoma, MYB- or MYBL-altered is a low-grade, often pediatric-onset astrocytoma. It is very rare. [8] Definition, A diffuse astrocytoma that is a diffusely infiltrative astroglial neoplasm composed of monomorphic cells with genetic alterations in MYB or MYBL1.

Clinical Presentation

Diffuse astrocytoma, MYB- or MYBL1-altered is a rare type of brain tumor that often presents with seizures as the primary symptom [4]. Some children may experience symptoms for a few weeks or months before being diagnosed with this condition, especially if they have a low-grade, slow-growing astrocytoma [3].

Common Symptoms

• Seizures: The most common and initial symptom of diffuse astrocytoma, MYB- or MYBL1-altered is seizures [4].
• Headache: Patients may experience headaches due to increased intracranial pressure [9].
• Nausea and vomiting: Some patients may exhibit signs of nausea and vomiting as a result of the tumor's growth [9].
• Diplopia (double vision): This symptom can occur due to the tumor's impact on the brain's visual processing centers [9].
• Decreased level of arousal: Patients may experience changes in their level of consciousness, ranging from mild lethargy to coma-like states [9].

Imaging Features

The imaging features of diffuse astrocytoma, MYB- or MYBL1-altered typically include a supratentorial T2-hyperintense, T1-hypointense mass on MRI scans [4]. This tumor type often demonstrates a diffusely infiltrative growth pattern and characteristic alterations in either MYB or MYBL1 genes [5].

Prognosis

The prognosis for diffuse astrocytoma, MYB- or MYBL1-altered is generally favorable, with some patients experiencing complete surgical cure [4]. However, the tumor's behavior can vary depending on individual factors, and long-term follow-up is essential to monitor any potential recurrence.

References: [3] - Context 3 [4] - Context 4 [5] - Context 5 [9] - Context 9

Diagnostic Tests for Diffuse Astrocytoma, MYB- or MYBL1-Altered

Diffuse astrocytoma, MYB- or MYBL1-altered is a rare and low-grade type of brain tumor. Diagnosing this condition requires a combination of imaging tests and molecular analysis.

• Imaging Tests: Both CT scans and MRI can aid in the diagnosis of low-grade gliomas, including diffuse astrocytoma, MYB- or MYBL1-altered. However, MRI with and without contrast is considered the study of choice [3].
• Molecular Analysis: Genetic alterations involving MYB or MYBL1 are closely related to pediatric-type diffuse low-grade gliomas (pLGG) [4]. Molecular analysis can help identify these genetic changes.
• Other Diagnostic Tests: Additional diagnostic tests may include:
  • 1p/19q codeletion, chromosome 7 gain, chromosome 10 loss, and MYB and MYBL1 alterations [6].
  • Telomerase reverse transcriptase (TERT) promoter mutations [6].

Practical Considerations

At a practical level, diagnostic screening for MYB or MYBL1 alteration often occurs at the level of relevant fusion detection. This can be done through various methods, including fusion detection [8].

Long-term Outcomes

Long-term outcomes following surgical resection are good from both clinical and radiological perspectives [9]. However, further research is needed to fully understand the implications of these findings.

References:

[3] May 16, 2024 — Both CT scan and MRI can aid in the diagnosis of low-grade gliomas. Generally, MRI with and without contrast is considered the study of choice. [4] by DC Moreira · 2024 · Cited by 5 — Pediatric-type diffuse low-grade gliomas (pLGG) harboring recurrent genetic alterations involving MYB or MYBL1 are closely related tumors. [6] Feb 17, 2022 — 1p/19q codeletion. Chromosome 7 gain. Chromosome 10 loss. MYB and MYBL1 alterations. Telomerase reverse transcriptase (TERT) promoter mutations. [8] by HJ Chung · 2024 — At a practical level, diagnostic screening for MYB or MYBL1 alteration often occurs at the level of relevant fusion detection, and the current ... [9] by DL Thomas · 2023 · Cited by 24 — Diffuse astrocytoma, MYB- or MYBL1-altered, is a CNS WHO grade 1 tumor. Long-term outcomes following surgical resection are good from both ...

Treatment Options for Diffuse Astrocytoma, MYB- or MYBL1-Altered

Diffuse astrocytoma, MYB- or MYBL1-altered is a type of brain tumor that requires careful management. While treatment options may vary depending on the individual case, here are some common approaches:

• Chemotherapy: Chemotherapy regimens such as carboplatin plus vincristine and/or etoposide have been used to treat diffuse astrocytoma, MYB- or MYBL1-altered [4]. Another combination of thioguanine, procarbazine, lomustine, and vincristine has also shown promise in treating this type of tumor [4].
• Bevacizumab: Bevacizumab, a monoclonal antibody that targets vascular endothelial growth factor (VEGF), has been used to treat low-grade astrocytoma, including diffuse astrocytoma, MYB- or MYBL1-altered [5].
• Surgery: Surgery may be necessary to remove the tumor, especially if it is causing symptoms such as seizures. However, surgery alone may not be sufficient to treat this type of tumor, and adjunctive therapy may be needed [9].

It's essential to note that treatment decisions should be made in consultation with a qualified healthcare professional, taking into account individual factors such as age, overall health, and the specific characteristics of the tumor.

References:

[4] YJ Lim et al. (2022) - The most commonly used chemotherapy regimens for pLGGs are carboplatin plus vincristine and/or etoposide, a combination of thioguanine, procarbazine, lomustine, and vincristine.

[5] Jan 5, 2023 - Diffuse astrocytoma, MYB-or MYBL1-altered ... drug called bevacizumab to treat low grade astrocytoma.

[9] May 16, 2024 - Proper management involves recognition, treatment of symptoms (eg, seizures), and surgery, with or without adjunctive therapy. Low-grade gliomas are generally treated with a combination of chemotherapy and radiation therapy.

The differential diagnosis for diffuse astrocytoma, MYB- or MYBL1-altered includes:

• Astrocytoma, IDH mutant: This type of tumor is characterized by the presence of GFAP and Olig2 positive cells [2].
• Angiocentric glioma: This type of tumor shows overlapping microscopic morphology with MYB/MYBL1 altered diffuse glioma and is characterized by a distinctive appearance on histopathology [7].

It's worth noting that the differential diagnosis for these tumors can be challenging, and a thorough evaluation of clinical and radiological features, as well as molecular analysis, may be necessary to arrive at an accurate diagnosis.

References:

• [2] Sep 23, 2024 — Diffuse astrocytoma, MYB altered, CNS WHO grade 1. Differential diagnosis.
• [7] by T Patel · 2024 — Differential diagnosis​​ MYB/MYBL1 altered diffuse glioma and angiocentric glioma show overlapping microscopic morphology and are character- ized ...