Mya-Thymektomie: The influence of minimally invasive thymectomy on the course of myasthenia gravis

Study Description:
Myasthenia gravis (MG) is a rare disease that leads to the impairment of communication between muscles and nerve cells. This results in a load-dependent muscle weakness which often initially manifests itself in the area of the eye muscles. In some patients, generalization can occur, i.e. the muscle weakness spreads throughout the body. It is usually caused when autoantibodies (immune proteins that mistakenly target a person’s tissues and organs) attack the neuromuscular synapse. Incorrect regulation of the immune system has been shown to be responsible for the formation of these autoantibodies.

The thymus, a specialized organ of the immune system, plays an important role in this process. In 10-15% of MG sufferers, a tumor is found in the thymus, the removal of which leads to significant improvement in myasthenic symptoms.

Thanks to a large study which published its results in 2016, it has been possible to prove that even in MG patients without a tumor, surgical removal of the thymus gland leads to an improvement in myasthenic symptoms (MGTX study). Therefore, it has been concluded that MG patients should be treated surgically in addition to drug therapy.

With regard to surgical treatment, there are various surgical techniques that can be used to remove the thymus gland. It has not yet been sufficiently clarified, however, whether the different procedures are equivalent in terms of their effect on myasthenia gravis and their degree of safety. Our present study seeks to clarify this question and contribute to its answer.

In the study, we will examine two groups of participants. F200 MG patients who underwent minimally invasive thymectomy (Tmin-group) will be the first participants in the study. The data regarding the disease and therapy (especially on the thymectomy performed) of these patients will then be compared with data that has already been analyzed in the MGTX study mentioned above, which investigated patients who had an open thymectomy. In addition to this, we would like to survey 200 MG patients who did not have thymectomy (T0-group). Comparing these groups of patients may provide us with information about the long-term effect of thymectomy.

Principal Investigator: Prof. Dr. Andreas Meisel