Mediastinal tumours are abnormally growing tissues within the chest cavity between the lungs, called the mediastinum. These tumours compress important organs like the heart, oesophagus, and trachea, causing serious health issues. That’s why detecting them early and monitoring their growth is important to prevent damage to these vital organs. This blog will outline the growth rate of these tumours, what symptoms to watch out for, and why early detection could be life-saving.
What Is a Mediastinal Mass?
While “mediastinal mass” and “mediastinal tumour” both involve growths found in the mediastinum, they don’t necessarily mean the same thing. A mediastinal mass is a much broader term and usually describes a non-cancerous (benign) growth, like benign teratomas or cysts, while a mediastinal tumour means a cancerous (malignant) growth1. Many mediastinal masses are non-cancerous, but they may still compress vital organs, causing serious health concerns2.
Common types include thymomas, lymphomas, and germ cell masses, usually found in the anterior (front) mediastinum. In some people, a warning sign of cancer may include mediastinal adenopathy (swollen lymph nodes in the mediastinum), so keeping an eye on these warning signs can help with early detection3.
Location and Function of the Mediastinum
The mediastinum is found in the middle of the chest between the sternum (breastbone) and spine1. Tumours that develop in the mediastinum are dangerous because they can put pressure on vital organs like the heart, oesophagus, and trachea, which are all essential for a healthy and functioning body4.
Common Types of Mediastinal Tumors
Thymoma - Typically slow growing and develops in the thymus gland, an essential organ in the immune system. This gland produces white blood cells and is critical for the body to fight infections and disease5.
Lymphoma - Typically fast growing, and develops in the lymphatic system, a critical part of the immune system’s defence. Examples of lymphomas include Hodgkin lymphoma and non-Hodgkin lymphoma6.
Germ cell tumours - Develop from germ cells (cells which make sperm and eggs) growing outside the ovaries and testes. They can be categorised into seminomas, which tend to be slower growing, and non-seminomas, which are faster growing1.
Neurogenic tumours - Develop from nerve tissue and are one of the most common mediastinal tumours found in the posterior (back) mediastinum7.
Is Mediastinal Adenopathy Cancer?
Mediastinal adenopathy means the swelling of lymph nodes in the chest. It can be a sign of infection, like upper respiratory infections, or inflammatory conditions. But it could also be a red flag for cancer, like Hodgkin and non-Hodgkin lymphoma3. When signs of mediastinal adenopathy are present, it’s important to talk to healthcare providers. They may recommend carrying out imaging tests, like a chest X-ray, computer tomography (CT) or magnetic resonance imaging (MRI) scan, which can help detect abnormal tissues.
Mediastinal Cancer Symptoms
Respiratory and Chest Symptoms
Symptoms of a mediastinal tumour are usually due to important organs like the heart, lung, and airway being compressed; they can include1:
- Trouble swallowing
- Cough
- Wheezing
- Shortness of breath
- Hoarseness
- Coughing up blood
Systemic Symptoms
Some people also experience systemic symptoms like fatigue, unexplained weight loss, fever, chills, and night sweats8.
When to Seek Medical Advice
Early screening is the best way to detect abnormalities, especially if symptoms persist or worsen. Mediastinal tumours may remain silent as they develop, not producing any symptoms. As a result, they’re usually discovered at a late stage, and even accidentally after imaging tests for an unrelated health issue9.
How Fast Do Mediastinal Tumors Grow?
Mediastinal tumours grow at different rates depending on the type of tumour. For example, lymphomas typically grow fast, requiring urgent medical attention for the best possible outcome, whereas thymomas tend to grow more slowly, but still need careful monitoring5,6,8. Imaging techniques, such as CT and MRI scans, are essential in detecting abnormalities and monitoring how well the tumour responds to treatment.
Role of Imaging in Monitoring Growth
Imaging techniques like CT and MRI scans are great tools for detecting abnormalities, such as mediastinal masses and tumours. They can help determine the tumour’s size, shape, and whether it has spread.
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Importance of Biopsy
If imaging detects abnormalities, a biopsy of the tissue (mediastinoscopy) is typically the next step to check for cancer and guide treatment decisions9.
Factors That Influence Tumor Growth
Tumour type - Slow-growing mediastinal tumours include thymomas, whereas aggressive tumours like lymphomas and non-seminoma germ cell tumours tend to grow faster1,5,6
Immune response - Inflammation from a collection of immune cells in the mediastinum has been linked to increased tumour growth10
Location - Anterior (front) and posterior (back) mediastinal tumours grow at varying rates, depending on the type of mediastinal tumour and areas of the body they impact4
Stage - Early-stage tumours often grow slowly and stay in one area of the body, while late-stage tumours are generally more advanced, grow faster, and may spread to other parts of the body11
Diagnosis & Stages
Imaging tools like chest X-ray, CT, MRI, and positron emission tomography (PET) scans help detect mediastinal masses and tumours. The next step is usually a biopsy to confirm cancer and determine its stage (I-IV), based on the location of the primary tumour, whether it has spread to nearby lymph nodes, and whether it has spread to distant parts of the body11. Early-stage tumours may be treated by surgery, whereas advanced tumours (stage III-IV) often require radiation therapy and/or chemotherapy.
Stage I - Tumour is in the mediastinum with no spread to other parts of the body
Stage II - Mediastinal metastasis (spread of tumour) to surrounding tissues or lymph nodes within the mediastinum
Stage III - More extensive spread to nearby organs such as the lungs, heart, or major blood vessels
Stage VI - Cancer has spread to distant parts of the body, such as the bones or liver
Mediastinal Metastasis
Sometimes mediastinal tumours can spread to other parts of the body, which is called metastasis. The sites for metastasis usually depend on the type of mediastinal tumour; for example, germ cell tumours typically spread to the lungs and lymph nodes12. Catching abnormalities early significantly reduces the chances of metastasis, so it’s important to catch and treat the cancer quickly.
Mediastinal Tumor Survival Rate
Survival rates vary widely depending on the type and stage of mediastinal tumour. Early detection of mediastinal tumours significantly increases the chances of survival.
Survival by Tumor Type
The 5-year survival rates can vary depending on the type of mediastinal tumour, since each type may respond differently to treatment.
Thymoma - Survival rates for thymomas depend on the stage, with stage I having a more favourable prognosis of 96 per cent survival, whereas stage IV has a survival rate of 50 per cent 14
Lymphoma - Hodgkin and non-Hodgkin lymphomas are reported to have a 5-year survival rate of around 80 per cent and 65 per cent, respectively 15,16
Germ cell tumour - The 5-year survival rate for seminomas is 87.7 per cent compared to 23 per cent for patients with non-seminomatous germ cell tumours17.
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Survival by Stage
Early-stage mediastinal tumours have greater survival rates compared to late-stage mediastinal tumours. For example, thymomas are reported to have a 5-year survival rate of 96 per cent for stage I, 86 per cent for stage II, 69 per cent for stage III, and 50 per cent for stage IV14. Timely diagnosis is crucial, as early detection leads to more effective treatment and much better outcomes.
Is Mediastinal Cancer Curable?
The type and stage of mediastinal cancer, along with access to treatment, play a significant role in determining its curability. Early-stage mediastinal cancers often require surgery, while radiation, chemotherapy, and sometimes immunotherapy might also be considered for the treatment of late-stage cancers. Imaging is essential for tumour detection and tracking responses to treatment19.
Curability by Tumor Type
When it comes to early-stage mediastinal cancers, such as thymomas, they can often be removed with surgery20. For other types of mediastinal cancers, like lymphomas and germ cell tumours, treatment typically involves surgery, chemotherapy, and/or radiation.
Treatment Outlook by Stage
Catching mediastinal cancer early leads to better outcomes. When detected at an early stage, healthcare providers may be able to carry out surgery without the need for aggressive treatments like chemotherapy or radiation. Also, the sooner cancer is found, the lower the risk of it spreading to other parts of the body.
How Ezra Can Help
At Ezra, we offer safe and painless MRI scans. Our scans are ultra-sensitive and accurate, providing quick results that can screen for early abnormalities, even in the mediastinum. If you are experiencing persistent or worsening symptoms, it’s a good idea to talk to your healthcare provider and think about scheduling an MRI scan with Spine with us.
Summary
Mediastinal tumours grow in the chest cavity between the lungs. The growth rate of these tumours varies significantly depending on the type and behaviour of the mediastinal tumour. If you’re experiencing unexplained or worsening chest symptoms or are concerned about the risk of developing cancer, consider being proactive about your health and undergoing preventive screening. Early detection of abnormalities significantly improves outcomes.
Ezra offers fast, non-invasive full-body MRI scans that can detect abnormalities in up to 14 organs. Take control of your health with early detection—book your Ezra Scan today.
