====== Central Nervous System Germ Cell Tumor ======


**[[Central Nervous System]] [[Germ Cell Tumor]]s (CNS GCTs)** are rare tumors originating from [[germ cell]]s that abnormally migrate and become lodged in the [[central nervous system]] (CNS). These tumors are most commonly found in [[child]]ren and [[young adult]]s, typically presenting in the [[pineal]] or [[suprasellar region]]s of the brain.

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===== Classification of CNS GCTs =====

CNS germ cell tumors are broadly categorized into two groups:

1. **[[Germinoma]]s**:
   - The most common type of CNS GCT.

   - Highly sensitive to radiation and chemotherapy.

   - Typically have a favorable prognosis.

2. **Non-Germinomatous Germ Cell Tumors (NGGCTs)**:

   - Include teratomas, yolk sac tumors, embryonal carcinomas, and choriocarcinomas.

   - More aggressive than germinomas.

   - Often requires intensive multimodal therapy.

   - May secrete markers such as [[alpha-fetoprotein]] (AFP) or [[beta-human chorionic gonadotropin]] (β-hCG).

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Common Locations:

- **Pineal Region**: Germinomas are frequently found here, often causing symptoms due to compression of surrounding structures.

- **Suprasellar Region**: May affect the pituitary-hypothalamic axis, leading to hormonal imbalances.

- **Other Sites**: Rarely, these tumors can occur elsewhere in the brain or spine.

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Symptoms:

Symptoms depend on the tumor's location and size, often including:

1. **Increased Intracranial Pressure** (e.g., headaches, nausea, vomiting, papilledema):
   - Due to hydrocephalus from obstruction of cerebrospinal fluid (CSF) flow.

2. **Neurological Symptoms**:

   - Double vision, ataxia, or weakness, depending on the affected brain region.

3. **Endocrine Dysfunction** (especially in suprasellar tumors):

   - Diabetes insipidus.

   - Delayed or precocious puberty.

   - Hypopituitarism.

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===== Diagnosis =====

see [[Germ Cell Tumor diagnosis]].



### Treatment:
1. **Germinomas**:
   - **Radiation Therapy**: Mainstay of treatment, often with curative intent.
   - **Chemotherapy**: Used in conjunction with radiation to reduce the radiation dose and long-term side effects.

2. **Non-Germinomatous Germ Cell Tumors (NGGCTs)**:
   - **Multimodal Approach**:
     - Surgery for resection when feasible.
     - Chemotherapy (e.g., cisplatin-based regimens).
     - Radiation therapy tailored to the extent of the disease.

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### Prognosis:
1. **Germinomas**:
   - 5-year survival rate >90% with appropriate treatment.
2. **NGGCTs**:
   - Prognosis varies by subtype and extent of disease.
   - Tumors secreting high levels of AFP or β-hCG often have a poorer prognosis.

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### Follow-Up:
Patients require long-term monitoring for:
1. Recurrence through imaging and tumor marker levels.
2. Late effects of therapy, including neurocognitive impairment, endocrine dysfunction, and secondary malignancies.

CNS GCTs, though rare, are often treatable with a combination of surgery, radiation, and chemotherapy, particularly when detected early. Multidisciplinary care is essential for optimizing outcomes.