A thymotomy is the surgical removal of the thymus gland, a small organ located in the upper chest behind the breastbone. As a component of the immune system, the thymus supports the development of specialized white blood cells called T-cells, which attack foreign invaders like viruses and bacteria. The thymus is most active and largest during infancy and childhood, playing a role in building a person’s immunity. After puberty, it begins to shrink and is largely replaced by fatty tissue in adults.
Medical Reasons for a Thymotomy
A common reason for a thymotomy is to treat Myasthenia Gravis (MG), an autoimmune disorder causing muscle weakness. In many people with MG, the thymus gland is abnormal and may be swollen, a condition known as thymic hyperplasia. The gland is thought to produce abnormal antibodies that disrupt nerve-to-muscle communication. Removing the thymus can help rebalance the immune system, reduce muscle weakness, and lower the need for medication.
The procedure is also the primary treatment for tumors of the thymus gland. These growths, called thymomas, are often slow-growing and benign (non-cancerous), while malignant tumors are called thymic carcinomas. Surgery is performed to remove these tumors to prevent them from growing and spreading to nearby organs.
A thymoma is sometimes discovered during the diagnosis for Myasthenia Gravis, as about 10% of people with MG have one. In these cases, removing the thymus and the tumor can improve MG symptoms while also treating the growth.
Types of Thymotomy Procedures
The traditional method is a transsternal thymectomy, a type of open-chest surgery. A surgeon makes a long vertical incision and divides the sternum (breastbone) to gain a direct view of the thymus. This approach allows for the thorough removal of the entire gland and adjacent fatty tissue and is often preferred for large tumors.
Modern, less invasive techniques avoid a full sternotomy. One common approach is Video-Assisted Thoracoscopic Surgery (VATS), where a surgeon uses several small incisions to insert a tiny camera and specialized instruments. This allows the surgeon to view the thymus on a monitor and remove it without opening the chest.
Robotic-Assisted Thoracoscopic Surgery (RATS) is an advanced version of VATS where the surgeon operates from a console. The surgeon’s hand movements are translated into precise movements of robotic arms, offering a magnified 3D view and enhanced dexterity. The choice between open and minimally invasive surgery depends on tumor size, location, and the patient’s health.
The Surgical and Recovery Process
A thymotomy is performed under general anesthesia, with a hospital stay that typically lasts a few days. This stay may be shorter for minimally invasive surgeries compared to an open sternotomy. After the operation, patients are monitored in a recovery area before being moved to a hospital room, and pain is managed with medication.
A common aspect of recovery is the presence of one or more chest tubes. These flexible tubes are placed in the chest during surgery to drain any excess fluid or air that might accumulate around the lungs. The tubes are connected to a drainage system and are usually removed a day or two after surgery once the drainage has subsided.
Upon discharge, patients receive instructions for home recovery. These guidelines include activity restrictions for several weeks, such as avoiding heavy lifting, strenuous exercise, and driving to allow for proper healing. Follow-up appointments are scheduled to monitor progress.
Long-Term Outcomes and Life After Surgery
Long-term results of a thymotomy vary depending on the reason for the surgery. For individuals with Myasthenia Gravis, the benefits are often gradual and may not be fully realized for months or even years. Over time, many patients experience a significant reduction in muscle weakness and a decreased need for immunosuppressive medications. A notable portion may enter remission, meaning they have no symptoms of the disease.
For patients who undergo a thymotomy for a thymic tumor, the outlook is positive, especially when the tumor is non-cancerous and fully enclosed. Surgical removal is often curative for a benign thymoma. If the tumor is an invasive thymoma or a thymic carcinoma, radiation or chemotherapy may be recommended after surgery. The prognosis depends on the cancer’s stage and whether it was completely removed.
Living without a thymus gland has little to no effect on an adult’s health. The gland’s role in immune system development is completed by puberty, after which it shrinks and becomes less active. In adults, other organs maintain a healthy immune response, so its absence does not make a person more vulnerable to infections. The body’s established T-cells continue to function for life.