Tumor 'Risk' a Myth

Adult stem cells do not increase tumor risk

One question that is regularly asked in connection with stem cell therapy is whether stem cells increase the risk of cancer. This is a justified concern if a therapy involves embryonic stem cells because these cells actually do divide at an extremely fast rate, and they have already been shown to have cancer-causing potential in animals and humans. However, therapy with embryonic stem cells is strictly prohibited in Germany. At the XCell-Center, we only use the patient's own stem cells for therapy.

The following applies for therapy with adult stem cells:

Adult stem cells, which are transplanted immediately after their removal and concentration for therapeutic purposes, do not increase the risk of tumor unless the patient already has cancer.

This was also the conclusion drawn by the German Bundestag's Scientific Service in April 2007 after the evaluation of scientific studies.*

Here are the facts based on the current information status:

Fact 1: No indications of higher tumor formation have been found to exist over the last 40 years in the therapy of leukemia and lymphoma, which also involves the use of adult stem cells.

Fact 2: The behavior of adult stem cells depends to a great extent on their environment. There is no evidence to date that adult stem cells promote tumor formation in the human body.

There is one exception. The growth of an existing tumor can be promoted by the insertion of adult stem cells, and tissue that is damaged by irradiation can harden into cancerous tissue after the injection of adult stem cells.

Fact 3: Adult stem cells only tend to form cancerous stem cells if they are allowed to multiply in a culture dish over a lengthy period of time, because the probability of genetic defect clusters increases in proportion to the number of cell divisions.

Summary: In accordance with the latest scientific findings, the therapy performed at the XCell-Center does not cause tumors because the stem cells are not allowed to multiply for any length of time outside the body. They are transplanted back into the body immediately after purification. The XCell-Center doesn't treat patients with tumors.

*Source: Donner, Susanne (2007) Zusammenhang zwischen der Krebsentstehung und adulten bzw. embryonalen Stammzellen. Draft of the German Bundestag's Scientific Service, 7 April 2007.