What is Thymoma?
Thymoma is a tumor arising from the thymus gland located behind the breastbone. The thymus gland is the main site of production of T-lymphocytes in the body’s defense system until puberty. After puberty, the thymus gland loses its function and shrinks. Tumors arising in the thymus gland are called thymomas.
What are the Symptoms of Thymoma?
Thymomas may not cause any symptoms. If they continue to grow, they can cause pain in the anterior chest region, pressure on the trachea and cause bronchitis-like coughs. If they get bigger, they can cause significant swelling of the face, prominent neck veins, excessive redness of the face (vena cava superior syndrome) and shortness of breath by pressing on the surrounding veins. However, these cases are extremely rare. In general, patients with thymoma do not have any symptoms.
About 15% of patients with thymoma have a nerve conduction disorder called Myasthenia Gravis. In Myasthenia Gravis, patients have difficulties in seeing (as a result of eyelid drooping), swallowing and sometimes breathing. However, the most prominent complaint in patients with myasthenia is fatigue that occurs in the entire muscle system later in the day.
In patients with thymoma, sometimes anemia, skin rashes, Kaposi’s sarcoma and many similar disease states that are not related to the thymoma itself may occur. These conditions, called para-neoplastic syndrome, improve with the treatment of thymoma.
Thymoma Stages
There are four stages of thymomas.
First Stage Thymoma
At this stage, the tumor is confined to a capsule. In the picture on the right, there is a computed tomography image of thymoma in a 67-year-old female patient. The red arrow indicates the thymoma located behind the sternum and in front of the heart. Since it is seen that the tumor does not spread to the surrounding vessels, it can be understood with these images that it is a 1st or 2nd stage thymoma. Definitive diagnosis is made as a result of pathology examination.
Second Stage Thymoma
At this stage, the tumor extends outward by causing damage (invasion) in its capsule. It may not be possible to distinguish between the first and second stages with computed tomography images. This distinction is made as a result of the pathology examination of the removed tumor.
Third Stage Timoma
At this stage, the thymoma passes through the capsule and progresses towards the surrounding structures such as the lungs, trachea, veins, and pericardium.
Fourth Stage Thymoma
At this stage, thymoma has spread / spread to other organs (eg, lung, liver, adrenal gland).
Tymoma Stage 4A
In stage 4A of thymoma, the tumor spreads to the lung or pleura. This can be called metastasis, not spread, but pleural implants. It is a different picture than the situation called spreading to other organs.
Tymoma Stage 4B
In stage 4B of thymoma, there is spread to more distant organs.
How Is Thymoma Diagnosed?
Radiological Thymoma Examination
Plain chest radiographs do not have an important place in the diagnosis of thymomas. A normal plain chest radiograph does not exclude the presence of a thymoma. Computed tomography images give very detailed information on this subject. In some cases, MRI may also be needed. In doubtful cases, PET-CT may be necessary. This is not always required.
Thymoma Biopsy with Needle
Needle biopsy is not required in regularly circumscribed tumors that are capable of surgery (stages 1 and 2), however, biopsy is essential for the diagnosis of stage 3 and stage 4 thymomas.
Thymoma Treatment
If patients have Myasthenia Gravis, it should first be treated with medication appropriately. This treatment is administered by the neurology clinic. When Myasthenia Gravis reaches a certain control, thymoma treatment is started.
Thymoma treatment is related to the stage in which thymoma is present.
IMPORTANT
Thymoma is an extremely serious tumor.
If it is evaluated as a simple and benign tumor and not treated appropriately, it has important consequences.
Treatment of First and Second Stage Thymoma
At these stages, the thymoma must be surgically removed.
No other treatment such as chemotherapy or radiotherapy is required after surgery.
Patients should be followed up every 6 months for 5 years. Then, a check is made once a year.
Third Stage Thymoma Treatment
If the surgeon predicts that he or she can FULLY remove a stage 3 thymoma, the tumor is surgically removed. Then radiotherapy is applied for about 6 weeks.
If the surgeon predicts that the tumor cannot be completely removed by surgery, then chemotherapy (drug therapy) and radiotherapy (radiation therapy) are applied and the tumor is surgically removed after the spread of the tumor to the surrounding tissues is regressed.
It may be necessary to continue chemotherapy after surgery. Whether chemotherapy is needed is decided by the hospital’s tumor board.
After the treatment, she is followed up every 3 months for 2 years and every 6 months for the next 3 years. Then a control is applied once a year.
In the picture above, there is a computed tomography image of a female patient with thymoma in stage 3. After chemotherapy and radiotherapy were applied to our patient, the spread to the vessels was eliminated, the tumor was surgically removed.
Treatment of Stage Four Thymoma
4A Stage: If applicable, the tumor and its spread are surgically removed, followed by chemotherapy and radiotherapy.
Phase 4B: Surgery is no longer performed, as the spread to other organs has occurred at this stage. Only chemotherapy and radiotherapy are applied when necessary.
Thymoma Surgery Methods
Open and closed methods are used in thymoma surgeries.
Our preferred method is closed (single port VATS) operation.
Thymoma Surgery – Open Method
It is the process of removing the tumor (thymoma) located under the breastbone by open surgery.
There are 2 approaches for open surgery:
A) Opening of the sternum (sternotomy)
B) Opening between the ribs (thoracotomy)
The tumor should be completely removed and the surrounding fatty tissues should be removed during the surgery.
The average hospital stay is 4 or 5 nights.
Open method is preferred in the surgery of third and fourth stage thymomas.
Complication rate of the operation is 5-10% in experienced centers.
Thymoma Surgery – Closed Method (Single Port Thoracoscopy, VATS)
In the closed surgery method, which we call single port VATS, a 3 cm incision is made and an image is obtained with a camera advanced from the lateral part of the chest, and the thymoma and surrounding fatty tissues are removed in a special bag (endobag).
It is an operation that requires special experience.
It is the least harmful method to the patient.
The hospital stay is 2 nights.
It can be applied in first and second stage thymomas.
Return to normal life is shorter than the open method. The complication rate is 5%.
Thymic Hyperplasia
The thymus gland disappears after puberty. In some people, this disappearance does not occur and on the computed tomography, it creates an image in front of the heart, behind the breastbone. This condition, called thymic hyperplasia, does not require treatment. If this image creates a suspicion of thymoma, it should be removed with a closed operation with VATS method and pathology examination should be performed.