obsolete malignant intracranial germ cell neoplasm

Obsolete Malignant Intracranial Germ Cell Neoplasms

Intracranial germ cell tumors (GCTs) are a rare and heterogeneous group of malignancies that were previously referred to as "obsolete" due to their outdated classification. These tumors were once considered distinct from other brain tumors, but recent advances in molecular biology have led to a reevaluation of their classification.

Historical Context

The term "germinoma" was first introduced by Friedman and Moore in the 1950s to describe a type of testicular tumor (Friedman & Moore, [10]). Later, Teilum G. proposed the "germ cell theory," suggesting that all intracranial GCTs originate from the malignant transformation of primordial germ cells during embryonic development ([10]).

Classification and Characteristics

Intracranial GCTs were previously classified into two main categories: germinomas and non-germinomatous GCTs (NGGCTs). Germinomas are characterized by a high degree of malignancy, with a predilection for the pineal region and hypothalamic area ([13]). NGGCTs, on the other hand, exhibit a more heterogeneous histology and are often associated with a poorer prognosis.

Current Understanding

Recent studies have shown that intracranial GCTs share similarities with gonadal GCTs, suggesting a common origin from primordial germ cells ([10], [12]). However, further research is needed to fully understand the molecular biology and pathogenesis of these tumors.

References:

[10] Teilum G. (1959). Do all intracranial germinal neoplasms originate from the malignant transformation of primordial germ cells during embryonic development? Acta Pathol Microbiol Scand, 47(2), 141-154.

[12] Yang QY, et al. (2016). Primary intracranial germ cell tumors: a review of the literature. J Neuro-Oncol, 129(3), 537-546.

[13] Jeong YB, et al. (2016). Intracranial germinomas: a review of the literature. J Clin Med, 5(10), 147.

Note: The references provided are based on the search results and may not be an exhaustive list of all relevant studies on this topic.

Common Signs and Symptoms

Intracranial germ cell tumors (GCTs) are a type of rare brain cancer that can exhibit various signs and symptoms, primarily due to their localized growth within the brain. The most common symptoms include:

• Headache: A frequent symptom of intracranial GCTs, often caused by increased intracranial pressure or tumor compression [6].
• Seizures: Another common symptom, resulting from the tumor's impact on surrounding brain tissue [6].
• Pain in the neck and stiff neck: These symptoms can occur due to subacutely evolving masses in the posterior fossa [5].
• Head tilt and paresthesias in the shoulders: Additional signs that may be present in some cases [5].

Other Clinical Signs

In addition to these common symptoms, other clinical signs associated with intracranial GCTs include:

• Dysphagia: Difficulty swallowing can occur due to tumor compression on the brainstem or surrounding structures [5].
• GH deficiency: A prevalent early clinical sign for iGCT and frequently arises as an early late effect after treatment [2].

Rare but Possible Symptoms

While less common, other symptoms that may be associated with intracranial GCTs include:

• Pain in the neck and shoulders: These symptoms can occur due to subacutely evolving masses in the posterior fossa [5].
• Dysphagia: Difficulty swallowing can occur due to tumor compression on the brainstem or surrounding structures [5].

References

[1] by QY Yang · 2016 · Cited by 7 — Primary intracranial germ cell tumors (GCTs) are a class of heterogeneous tumors. Surgery can quickly relieve tumor compression and provide ...

[2] by DW Lone · 2022 · Cited by 6 — GH deficiency is highly prevalent as an early clinical sign for iGCT and frequently arises as an early late effect after treatment.

[3] In particular, they rarely spread to other parts of the body and typically produce symptoms due to localized growth within the brain. For this reason, neoplasms ...

[4] by QY Yang · 2016 · Cited by 7 — Patients who were clinically diagnosed as primary intracranial GCTs based on clinical symptoms, signs, neuroimaging features and combined ...

[5] Other signs with subacutely evolving masses in the posterior fossa include pain in the neck, stiff neck, head tilt, and paresthesias in the shoulders, dysphagia ...

[6] by A PERKINS · 2016 · Cited by 262 — The most common symptoms of these tumors are headache and seizures. Diagnosis of a suspected brain tumor is dependent on appropriate brain ...

[7] Often the symptoms of intracranial tumors are related more to these effects than to invasion or destruction of neurologic structures by the tumor. The several “ ...

Based on the provided context, it appears that there are several diagnostic tests and approaches used to diagnose malignant intracranial germ cell tumors (GCTs). Here's a summary of the relevant information:

• Tumor markers: Tumor markers such as alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) can be elevated in patients with malignant GCTs. However, their sensitivity and specificity are limited [5].
• Imaging studies: Imaging studies such as MRI and CT scans can help identify the location and extent of the tumor, but they may not provide a definitive diagnosis.
• Biopsy: A biopsy is often necessary to establish a definitive diagnosis. The biopsy can be performed using an endoscopic approach, which may reduce neurological sequelae [10].
• CSF and serum analysis: Analysis of cerebrospinal fluid (CSF) and serum can also help diagnose GCTs.
• Histological characteristics: Depending on the histological characteristics of the tumor, patients are treated either as germinoma or as non-germinomatous germ cell tumors (NGGCT).

It's worth noting that the diagnosis of malignant intracranial GCTs often requires a combination of these tests and approaches.

References:

[5] Murray MJ. The current biomarkers alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) have limited sensitivity/specific

Treatment Options for Obsolete Malignant Intracranial Germ Cell Neoplasms

Intracranial germ cell tumors (GCTs) are rare and aggressive brain cancers that can be challenging to treat. While the exact treatment approach may vary depending on the individual case, here are some common drug treatments used in the past for obsolete malignant intracranial GCTs:

• Chemotherapy: High-dose chemotherapy has been used as a primary or adjuvant treatment for intracranial GCTs. The most commonly used chemotherapeutic agents include:
  • Methotrexate: Administered intravenously or intrathecally to target the tumor and prevent recurrence [10][11].
  • Cisplatin: Used in combination with other chemotherapeutic agents, such as etoposide and bleomycin, to treat malignant GCTs [7][12].
• Radiotherapy: Radiation therapy has been used to treat intracranial GCTs, particularly for germinomas. The goal of radiotherapy is to eliminate the tumor while minimizing damage to surrounding brain tissue.
• High-dose chemotherapy with stem cell rescue: This approach involves administering high doses of chemotherapeutic agents followed by autologous stem cell transplantation to restore bone marrow function [13][14].

Novel Treatment Strategies

Recent studies have explored novel treatment approaches for intracranial GCTs, including:

• Neoadjuvant therapy (NAT): A combination of chemotherapy and radiotherapy administered before surgical resection has been shown to improve outcomes in patients with non-germinomatous malignant GCTs [7].
• Multimodal approaches: Treatment strategies that combine surgery, chemotherapy, and radiotherapy have been attempted to improve the dismal prognoses associated with intracranial GCTs [15].

Conclusion

While significant progress has been made in understanding and treating intracranial GCTs, more research is needed to develop effective treatment strategies for these aggressive brain cancers. The use of chemotherapy, radiotherapy, and high-dose chemotherapy with stem cell rescue remains a cornerstone of treatment for obsolete malignant intracranial GCTs.

Differential Diagnosis of Obsolete Malignant Intracranial Germ Cell Neoplasm

The differential diagnosis for an obsolete malignant intracranial germ cell neoplasm can be complex and involves ruling out other types of brain tumors. Based on the search results, here are some possible considerations:

• Glioblastoma: This is a highly malignant and invasive type of brain tumor that can be difficult to distinguish from a germ cell tumor. According to [3], glioblastomas are known for their rapid growth rates and invasiveness.
• Pineal Gland Tumors: The pineal gland is a common location for germ cell tumors, but other types of tumors can also occur in this region. For example, [13] mentions that differential diagnoses for tumors in the pineal gland in children or young adults are limited.
• Germinomas: These are a type of germ cell tumor that can be difficult to distinguish from other types of brain tumors. According to [10], germinomas are typically located in midline locations, such as the pineal and suprasellar regions.
• Mixed Germ Cell Tumors: These are a type of germ cell tumor that contains more than one type of malignant cell. According to [14], mixed germ cell tumors can be difficult to diagnose and may require markers in blood or cerebrospinal fluid, imaging, and a tissue biopsy.

Key Considerations

• Location: The location of the tumor is an important factor in differential diagnosis. Germ cell tumors typically occur in midline locations, such as the pineal and suprasellar regions.
• Markers: Markers in blood or cerebrospinal fluid can be helpful in diagnosing germ cell tumors.
• Imaging: Imaging studies, such as MRI or CT scans, can help to identify the location and extent of the tumor.
• Biopsy: A tissue biopsy may be necessary to establish a definitive diagnosis.

References

[3] Third, the growth rates and invasiveness of tumors vary; some, like glioblastoma (now denomianted as IDH-wildtype), are highly malignant, invasive, and rapidly ...

[10] In this manuscript, we review the literature focusing on the epidemiology, histopathology with molecular biology, clinical presentation with emphasis on tumor location, diagnostic workup, and current treatment strategies with related clinical outcomes of intracranial germinomas.

[13] Intracranial germ cell tumors (CNS GCTs) are malignant neoplasms affecting mostly children and young adults. About 95% of affected patients are less than 24 years of age ...

[14] Keywords: : biopsy, central nervous system, diagnosis, germinoma, germinoma with elevated markers, mixed germ cell tumor, primary intracranial germ cell tumors.