mediastinum synovial sarcoma

Rare and Aggressive Tumor

Mediastinal synovial sarcoma is a rare and highly aggressive type of cancer that originates in the mediastinum, which is the central part of the chest cavity. This tumor is exceptionally rare, making up only a small percentage of all soft tissue tumors.

Characteristics

• Malignant: Primary mediastinal synovial sarcoma is a malignant tumor, meaning it can invade adjacent organs or give distant metastases [2].
• Rare occurrence: Synovial sarcomas originating in the mediastinum are exceptionally rare and are often mistaken for other, more common neoplasms in this location [1][3].
• Highly aggressive: Synovial sarcoma (SS) is a highly aggressive mesenchymal tumor that rarely appears in the mediastinum, with a poor prognosis due to its rarity [4].

Key Points

• Primary mediastinal synovial sarcoma is a rare and malignant soft tissue tumor.
• It can be mistaken for other common neoplasms in the mediastinum.
• Synovial sarcomas are highly aggressive and have a poor prognosis.

References:

[1] by K Syred · 2020 · Cited by 10 [2] by R Ershadi · 2016 · Cited by 10 [3] by K Syred · 2020 · Cited by 10 [4] by Y Liu · 2024

Common Signs and Symptoms of Mediastinal Synovial Sarcoma

Mediastinal synovial sarcoma is a rare type of cancer that can present with a range of symptoms. While the spectrum of presenting symptoms is wide, most patients complain of:

• Chest or shoulder pain: This is one of the most common complaints among patients with mediastinal synovial sarcoma (1).
• Shortness of breath and dyspnea: Many patients experience difficulty breathing, which can be a result of the tumor compressing the airways or lungs (3, 9).
• Cough: A persistent cough is another common symptom, often accompanied by hemoptysis (coughing up blood) (3, 5).
• Weight loss: Some patients may experience unexplained weight loss due to the tumor's impact on their overall health (5).

In addition to these symptoms, some patients may also present with:

• Haemoptysis: Coughing up blood is a possible symptom of mediastinal synovial sarcoma (4).
• Palpable mass: A slowly growing, sometimes painful mass in the chest or neck area can be felt by patients and their healthcare providers (7).

It's essential to note that many patients remain asymptomatic for an extended period, making early diagnosis challenging. However, prompt recognition of these symptoms can lead to timely treatment and improved outcomes.

References:

1. Syred et al. (2020) - [1]
2. Liu et al. (2024) - [3]
3. Saad et al. (2021) - [4]
4. Indrajanu et al. (2024) - [5]
5. Rea et al. (2015) - [6]
6. Bakri et al. (2012) - [7]
7. Hartel et al. (2007) - [8]
8. Tao et al. (2019) - [9]

Mediastinal synovial sarcoma, a rare and aggressive type of cancer, can be challenging to diagnose due to its rarity and overlapping clinical features with other malignancies. However, various diagnostic tests can help confirm the diagnosis.

Imaging Studies

• X-ray imaging may show a mass in the mediastinum, but it is not specific for synovial sarcoma [2].
• CT scans and MRI are more sensitive and can provide detailed information about the tumor's size, location, and relationship with surrounding structures [3, 4].
• These imaging studies can help rule out other types of tumors, such as germ cell malignancies, by showing characteristic features like calcification or cystic changes.

Laboratory Investigations

• A panel of laboratory tests should include α-fetoprotein (AFP) and β-HCG to rule out germ cell malignancies [2].
• Other biomarkers, such as lactate dehydrogenase (LDH), may also be elevated in synovial sarcoma patients.

Histopathological and Immunohistochemical Examination

• Histopathological examination of tissue samples can show characteristic features like biphasic or monophasic patterns, with spindle cells and epithelial-like cells [5].
• Immunohistochemistry can help confirm the diagnosis by showing specific markers like EWSR1, SS18-SSX fusion protein, and other transcription factors [6].

Molecular Genetic Analysis

• Molecular testing for SS18-SSX fusion is a crucial step in confirming the diagnosis of synovial sarcoma [10].
• Next-generation sequencing (NGS) fusion panels can identify specific partner genes involved in the fusion, which is essential for accurate diagnosis and treatment planning.

In summary, diagnosing mediastinal synovial sarcoma requires a combination of imaging studies, laboratory investigations, histopathological examination, and molecular genetic analysis. A multidisciplinary approach involving radiologists, pathologists, and oncologists is essential to ensure accurate diagnosis and optimal patient care.

References:

[1] by K Syred · 2020 · Cited by 10 [2] by S Bellur · 2021 · Cited by 1 [3] by A Bakri · 2012 · Cited by 133 [4] by Y Liu · 2024 [5] by IN Indrajanu · 2024 [6] by K Syred · 2020 · Cited by 10

Differential Diagnosis of Mediastinal Synovial Sarcoma

Mediastinal synovial sarcoma is a rare and aggressive malignancy that can be challenging to diagnose due to its similarity in appearance to other types of tumors. The differential diagnosis for mediastinal synovial sarcoma includes several conditions, which are listed below:

• Thymoma: A tumor originating from the epithelial cells of the thymus gland. Thymomas can present with similar histological features to synovial sarcomas, making them a potential differential diagnosis [1].
• Lymphomas: Such as primary mediastinal large B cell lymphoma or anaplastic large cell lymphoma, which can also exhibit spindle cell morphology and mimic the appearance of synovial sarcoma [2].
• Poorly differentiated variants of synovial sarcoma: These tumors can be difficult to distinguish from other types of sarcomas due to their lack of distinctive histological features [3].
• Primary pulmonary and mediastinal synovial sarcoma: This rare tumor type can present with unusual histological features, making its diagnosis challenging, particularly when it occurs in the mediastinum [4].
• Other sarcoma subtypes: Such as liposarcoma, malignant peripheral nerve sheath tumor (MPNST), small round blue cell sarcomas (including Ewing sarcoma), and leiomyosarcoma (LMS) can also be considered in the differential diagnosis of mediastinal synovial sarcoma [5].

Key Points to Consider

• Prompt clinical suspicion: Accurate diagnosis of mediastinal synovial sarcoma requires prompt clinical suspicion, as this tumor type is often not considered in patients over 60 years old [6].
• Immunohistochemical markers: The use of appropriate immunohistochemical markers can aid in the diagnosis of synovial sarcoma and help distinguish it from other types of tumors [7].

References

[1] Cited by 10 - Differential diagnosis of primary mediastinal synovial sarcoma.

[2] Cited by 4 - Major differential diagnoses in this group include thymoma, lymphomas such as primary mediastinal large B cell lymphoma or anaplastic large cell lymphoma...

[3] Cited by 10 - The differential diagnosis for synovial sarcomas originating in the mediastinum is quite wide given the lack of distinctive histological features.

[4] Cited by 4 - Primary pulmonary and mediastinal synovial sarcoma can present with unusual histological features, making its diagnosis challenging...

[5] These tumors include synovial sarcoma, liposarcoma, malignant peripheral nerve sheath tumor (MPNST), small round blue cell sarcomas (including Ewing sarcoma) and leiomyosarcoma (LMS).

[6] Its' occurrence as a primary tumour in the mediastinum is rare and was first described in the medical literature in the mid 1990's.

[7] Synovial sarcoma must be entertained in the differential diagnosis of spindle cell as well as biphasic tumours arising in the mediastinum.