top of page


The thymus is a gland which sits toward the front of the chest, near the bottom of the neck. 


The thymus is involved in the immune system. 

The thymus is largest early in life and tends to atrophy or get smaller as a person ages. The thymus looks a bit like fat but has a slightly different consistency and is usually a bit more lobular (lumpy). 

In some people, the thymus does not atrophy and remains relatively large as an adult. 

Myasthenia gravis is an autoimmune disease associated with an enlarged thymus. Removing the thymus can often help improve myasthenia gravis. 

Some patients with myasthenia gravis develop a mass in the thymus; this is called a thymoma. About 20% of patients with myasthenia will develop a thymoma. Patients without myasthenia gravis can also develop a thymoma. 

A thymoma may be benign or it may be malignant. Usually the nature of the thymoma is determined by how far it has spread. Usually a CT scan is performed to determine how large a thymoma may be and how extensive it may have spread. 

Some patients with thymoma have symptoms and some do not. Roughly 1/3 of patients have symptoms such as cough or chest pain because the mass is pushing up against structures in the chest. About 1/3 of patients have an autoimmune disorder that leads to thymoma being found. And about 1/3 of patients have no symptoms. 

The treatment for thymoma is surgical removal (aka resection). 

If a thymoma looks very large on scan, after the diagnosis is confirmed with a biopsy, chemotherapy and/or radiation may be given in hopes of shrinking the thymoma and allowing it to be fully removed. If the thymoma is small, no additional therapy other than surgery is usually needed. 

Removing the thymus does not tend to have any bad effects on the immune system, at least in adults. 

Men and women develop thymomas at about the same rate. The usual age at diagnosis is 30-40 years, though a thymoma can develop at any age. 

Thymomas do not usually come back, but in 10-20% of cases and up to 10 years later, thymomas have been found in patients even after a complete resection. 

If a thymectomy needs to be done, there are a couple of options on how it can be done:



robotic pericardial window.jpg



A trans-sternal approach involves cutting thru the breastbone in order to remove the thymoma. 

The patient is put to sleep with a general anesthetic. 

The breastbone is cut and the thymus removed, with the thymoma inside it. It is important for the entire thymus to be removed. 

The breastbone is repaired using wires, which hold the bone in place and allow it to heal, much as with heart surgery. 

A trans-sternal approach usually takes 1-2 hours to perform. 

Patients are usually in the hospital 3-4 days after a trans-sternal approach. 

Dr. Pool prefers to use a robotic approach for most thymectomies. However, if the thymoma is large, a trans-sternal approach may be needed. Dr. Pool can advise you regarding the best approach for you, after he reviews your imaging. 

robotic pericardial window.jpg

A minimally-invasive method can often be used for thymectomy.

Dr. Pool has performed many thymectomies using the daVinci robot. 

The patient is put to sleep with a general anesthetic. 

Several small incisions - usually 4 - are made on the side of the chest. Each incision is less than in inch in size. 

A robotic thyemctomy usually takes 1-2 hours to perform. 

Patients are usually in the hospital 1 day after a robotic thymectomy. 

Dr. Pool usually prefers to access thru the right chest for robotic thymectomy, but can go thru the left side if needed. 

A video camera and the robotic instruments are inserted thru the small incisions. 

Aortic Stenosis
Thymectomy video
bottom of page