A mediastinal tumor is a growth that occurs in the space inside the chest, near organs such as the heart and lungs. Some of these tumors may cause symptoms, but some may not.

When mediastinal tumors cause symptoms, it is generally because they are pressing on surrounding structures. For example, a person may experience chest pain or pressure, coughing, or shortness of breath.

In this article, we explain what mediastinal tumors are, whether they are curable, their symptoms, diagnosis, and treatments.

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A mediastinal tumor is a growth of tissue that develops within the mediastinum. This is the area between the lungs that contains organs such as the heart, lungs, and esophagus.

Mediastinal tumors are rare. People usually get a diagnosis between the ages of 30 to 50, but the growth can develop at any age. The location and type of mediastinal tumor varies depending on the age of the person.

These tumors develop in one of three parts of the mediastinum:

  • the anterior (front)
  • the middle
  • the posterior (back)

In adults, mediastinal tumors are typically anterior, while in children, they are usually posterior.

There are many types of mediastinal tumors. This is because they can originate from many different types of tissue. For example, they can consist of:

  • nerve cells
  • germ cells, which come from testicular or ovarian tissue
  • lymph cells
  • thymus cells
  • parathyroid cells

The tumors can also be cancerous, which refers to malignant, or noncancerous, which refers to benign. Within the cancerous types, there are also slow-growing and aggressive types.

In children, mediastinal tumors are usually benign and occur in nerve cells. In adults, mediastinal tumors are often cancerous.

Whether a mediastinal tumor is curable depends on:

  • the type and stage of the tumor
  • location
  • whether it is cancerous

Noncancerous tumors are typically curable with treatment, while cancerous tumors can be more challenging to treat. The exact outlook will depend on a person’s specific situation.

For example, those with lymphoma at stage 1 or 2 generally have a positive outlook with standard treatments, with cure rates of 90%. At stage 4, cure rates are lower, at 50% to 60%.

It is important to note that each case is unique, and survival rates can differ significantly between individuals. People can get a more detailed outlook according to their circumstances from their doctor.

The symptoms of a mediastinal tumor can vary depending on its size, location, and whether it is pressing on nearby organs. Potential symptoms include:

It is important to note that not all mediastinal tumors cause noticeable symptoms. In fact, around half of anterior tumors cause no symptoms. A doctor may discover them during imaging tests for other medical conditions.

Diagnosing a mediastinal tumor involves a combination of a physical exam and imaging tests to help determine the size, location, and characteristics of the tumor. To do this, a doctor may recommend a:

In some cases, a blood test or biopsy may be necessary to confirm the type of tumor and determine whether the tumor is benign or malignant.

A biopsy involves removing a small sample of tissue from the tumor for examination under a microscope by a pathologist.

Each type of mediastinal tumor requires a custom approach to treatment, considering factors such as symptoms, the person’s health, and the type of tumor.

The options may include:

  • Surgery: This is the main treatment for noncancerous mediastinal tumors. It can also be an option for some cancerous tumors.
  • Chemotherapy: This involves using powerful medications to kill cancer cells. A doctor may use chemotherapy alone or in combination with surgery and radiation therapy.
  • Radiation therapy: This treatment uses high energy radiation beams to target and destroy cancer cells. A doctor may use it before or after surgery or in combination with other treatments.

Below are some frequently asked questions about mediastinal tumors.

Are mediastinal tumors fast growing?

This depends on the type of tumor a person has. Some tumors may grow slowly over time, while others may grow more rapidly.

What is the most common mediastinal tumor?

Mediastinal tumors most commonly occur at the front, or anterior part, of the mediastinum. These growths are often cancerous, with the most common tumor types including thymomas, thyroid cancers, lymphomas, and teratomas.

What percentage of mediastinal tumors are malignant?

Overall, around two-thirds of mediastinal tumors are benign, with one-third being malignant. However, among anterior tumors, which are the most common type, about 59% are malignant.

Mediastinal tumors are rare growths that develop within the mediastinum, or the cavity inside the chest. These tumors can originate from various tissues and may be benign or malignant.

Diagnosis typically involves imaging tests and may require a biopsy for confirmation. Treatment options include surgery, chemotherapy, and radiation therapy, depending on the type and stage of the tumor.

While the outlook for mediastinal tumors varies, early detection and treatment can improve outcomes.