Mediastinal tumor - specialists and information

A mediastinal tumor is a growth (tumor) in the mediastinum, the middle part of the chest. Tumors can be benign or malignant. The mediastinal tumor is a special case in oncology because it is located in the central space of the chest cavity. This is where vital organs, arteries, veins, nerves, lymph vessels and lymph nodes are located.

What does a mediastinal tumor mean for affected patients?

The mediastinum is located between the right and left lungs. The mediastinum is divided into an upper (mediastinum superius) and a lower (mediastinum inferius) functional area.

Mediastinum image @ pikovit / AdobeStock

Vital organs, vessels, nerves and lymph nodes are located in the mediastinum. Any suspicion of a tumor in this region should be taken very seriously. Those affected should therefore consult a specialist immediately.

Image of upper, middle, lower and posterior mediastinum @ pikovit / AdobeStock

The upper mediastinum - between the sternum and the thoracic spine

The upper mediastinum is located within the upper thoracic cavity. It extends from the first thoracic vertebra, the first pair of ribs, to the uppermost edge of the sternum towards the head. It extends downwards to the top of the pericardium and the base of the heart.

In addition to the division of the trachea and the main bronchi, it functionally comprises the following structures:

• Organs: thymus, windpipe (trachea), esophagus (trachea)
• Large blood vessels: arteries (aortic arch, left carotid artery, left subclavian artery, brachial artery trunk), veins (superior vena cava, right and left brachial vein)
• Nerves: tenth cranial nerve, retrograde laryngeal nerve, cardiac nerves, diaphragmatic nerves
• Lymph vessels: thoracic duct, right main lymphatic trunk, anterior and posterior mediastinal lymph nodes

The lower mediastinum

The lower mediastinum is divided from the sternum backwards (dorsally) into an anterior (mediastinum anterius), middle (mediastinum medium) and posterior areas (mediastinum posterius).

Anterior mediastinum (mediastinum anterius):

Contains blood vessels of small size such as the internal thoracic artery and the internal thoracic vein. It borders the sternum at the front and reaches the outer leaf of the pericardium at the back.

The parasternal lymph nodes are located on both sides of the sternum. The parasternal lymph nodes drain the pericardium, the female breast, the chest wall and the diaphragm. The thyroid gland is also part of the anterior mediastinum.

Middle mediastinum (mediastinum medium):

The heart, the ascending aorta and the trunk of the pulmonary artery are located here. The pericardial-diaphragmatic artery, the superior vena cava, the unpaired right thoracic wall vein, pulmonary veins, pericardial-diaphragmatic veins and diaphragmatic nerves are also located here.

Posterior mediastinum (mediastinum posterius):

The esophagus runs behind the heart. The thoracic vertebrae five to twelve form the outer, posterior border of the chest cavity. In between, the thoracic aorta and the unpaired right and left thoracic wall veins transport the blood. The sympathetic trunk, the tenth cranial nerve and the visceral nerves are parts of the nervous system that transmit signals throughout the body.

Symptoms of a mediastinal tumor

In the early stages, there are usually no symptoms. In the later stages, symptoms are typical of all tumor diseases:

• Fatigue
• anaemia
• weight loss
• Accelerated erythrocyte sedimentation rate (ESR)
• swelling of the lymph nodes
• fever
• night sweats

Pressure pain often occurs because the tumor enlarges and affects neighboring structures.

Typical symptoms of mediastinal tumors occur depending on the impaired tissue structure:

• Carcinoma of the esophagus(esophageal carcinoma): Pressure pain behind the breastbone and discomfort when swallowing, bad breath
• Thyroid tumor: enlarged lymph nodes, shortness of breath, difficulty swallowing, dry cough, hoarseness
• Tracheal and bronchial carcinoma: cough, dry irritating cough, hoarseness due to paralysis of the laryngeal nerve, drilling pain behind the sternum, shortness of breath with respiratory noises (stridor)
• Lymphoma (Hodgkin's disease): Gummous, painless swelling of a group of lymph nodes in the neck area along the large vessels
• Thymoma (tumor of the thymus gland): Upper influence congestion of the neck veins, shortness of breath, muscle weakness, pain behind the breastbone, cough, hoarseness
• Blood congestion in front of the heart: As a result of tumor-related vascular occlusion
• Neurinomas of the sympathetic trunk: triad of constricted pupil, sunken eyeball and drooping upper limb characterize Horner's syndrome due to nerve damage in the cervical part of the sympathetic nervous system
• Hiccups and elevated diaphragm
• Cardiac arrhythmia

How do mediastinal tumors develop?

All tissues of the mediastinum can grow larger and develop benign (benign) or malignant (malignant) tumors over time.

Benign tumors develop slowly and with clear demarcation from the surrounding area. The benign tumor displaces the neighboring tissue without destroying it and without forming metastases. Sometimes mediastinal tumors can develop from cysts, for example from a bronchogenic cyst.

Malignant tumors grow rapidly into the neighboring tissue (proliferation). They destroy the functional structure and form metastases.

Genetic predisposition plays a role in tumors. Specialists assume that the genetic information (deoxyribonucleic acid) is damaged. These genetic defects are passed on through germ cells (sperm, egg cells). They can therefore occur more frequently in a family.

The following key genes are responsible for this:

• Proto-oncogenes ensure the formation of proteins that the cell needs to divide and specialize
• Tumor suppressor genes control and inhibit cell growth
• Genes that regulate cell death

Risk factors that promote mediastinal tumors

Certain factors support the development of genetic defects in body cells that are responsible for malignant mediastinal tumors:

• Viruses: Oncogenic DNA and RNA viruses. They prevent the formation of enzymes and proteins that regulate cell growth and promote cell differentiation.
• Radiation: Ionizing radiation (radium radiation), X-rays and UV radiation.
• Chemical substances: Polycyclic hydrocarbons, silicates (asbestos), arsenic, nitrosamines, aromatics, mold toxins (aflatoxins), toxic metals, smoke and dust

• High-fat and low-fiber diet
• Consumption of stimulants: Cigarettes and alcohol
• Lack of exercise

Diagnosis of mediastinal tumors

Examination methods to determine the exact location:

• X-ray of the chest to produce an image for initial assessment as part of basic diagnostics
• Computer tomography using a contrast medium for detailed assessment of the soft tissue
• Nuclear medicine injection of radioactive substances(tumor markers) and creation of an image(scintigram)
• Endoscopy of the mediastinum, bronchi and oesophagus

Computed tomography examination in radiology @ Werner / AdobeStock

Histological examination methods:

Once the tumour has been localized , histological examination of the tissue is carried out to make a reliable diagnosis. The following steps are necessary for this:

• Removal of tissue (biopsy) for histological examination
• Microscopy of the removed tissue
• Assessment of cell growth as benign, malignant, semi-malignant
• Gradingof the malignant degeneration in comparison to normal findings (grading)

Therapy and treatment for mediastinal tumors

Surgical and conservative forms of therapy are used in the treatment of mediastinal tumors:

• Surgical therapy: Surgical therapy involves an operation to remove the tumor tissue. The aim is to remove all cells affected by the tumor.
• Radiotherapy: If doctors are unable to remove all the cancer cells surgically, radiotherapy is used. Radiotherapy aims to kill diseased tissue and preserve healthy tissue.
• Percutaneous (teletherapy): In teletherapy, radioactive particles or electromagnetic waves penetrate healthy tissue before reaching the tumor cells (at a greater penetration depth).
• Brachytherapy: This is a special form of radiotherapy. Radiologists irradiate the tumor with radioactive radiation sources from a short distance.
• Metabolic radiotherapy: By means of intravenous injection. Radioactive radiation destroys the tumor cells from the inside.
• Chemotherapy: Chemical substances (cytostatics) act on the tumor cells.
• Immunotherapy: Vaccination with attenuated pathogens, administration of interferon-alpha or interleukin-2 to stimulate the immune system

Which doctors are responsible?

The doctor who has been treating you up to now is the main contact person. He or she refers patients to specialized specialists, cancer centers, outpatient clinics or hospitals.

Today, several specialists are involved in outpatient or inpatient treatment. The type of cooperation varies from clinic to clinic. This is why there are oncological centers of excellence that are certified by the German Hospital Association.

Progression and prognosis

Malignant tumors can invade blood and lymph vessels, destroy the surrounding tissue and form metastases. Therefore, severe health impairments and negative psychological consequences are to be expected.

Surgical, chemical and radiological forms of cancer therapy are available today. Depending on the findings, it makes sense to combine several forms of therapy in order to increase the success of the treatment.

Digitalized procedures in radiology make it possible to plan and visualize interventions three-dimensionally. Radiotherapy is therefore precise and causes less damage to neighboring, tumor-free tissue.

Conclusion

Tumors in the mediastinum require rapid diagnosis and immediate treatment. The central and close location to vital organs and vessels makes the tumor dangerous. Malignant tumor cells can multiply and spread particularly well in the mediastinum.

When choosing a doctor, you should pay attention not only to their specialist expertise but also to your instincts. Trust in the doctors and facilities treating you plays a particularly important role in tumor treatment.