Can a bone marrow transplant cure blood cancer

Stem cell transplant in cancer

One from a donor is similar to an autologous one. The allogeneic of has two advantages, but also one major disadvantage.

One of the advantages: With the donated cells, certain immune cells are also transferred at the same time, which help fight any cancer cells that may still be present in the recipient's body. This beneficial effect is called the graft-versus-disease reaction. Another advantage: no cancer cells will be transmitted, as they come from a healthy person.

The disadvantage of this form is that the donor's immune cells can turn against tissue cells in the recipient's body. Such a reaction is called a graft-versus-host reaction (English graft-versus-host effect or graft-versus-host disease).

It can damage the skin, intestines and liver in particular. This acute graft-versus-host reaction is divided into four degrees of severity. A slight rejection reaction (grade 1), for example, leads to skin rashes, but has no influence on the success of the. More severe rejection reactions (grade 2 and higher), on the other hand, can trigger more severe symptoms and sometimes be life-threatening. They require intensive treatment.

Sometimes the rejection reaction lasts or occurs after a few months. Then one speaks of a chronic graft-versus-host reaction (Graft-versus-host reaction, GvHD). It is an inflammation-like immune reaction of the recipient's tissues.

Although it does not impair the production of new blood cells, it can cause various serious and very stressful symptoms such as breathing problems, joint pain, diarrhea and mucous membrane, skin or eye complaints. Other organs, such as the liver, can also be affected. Chronic rejection may require long-term medication.

In order to prevent a severe rejection reaction, it is important that the donor and recipient match as closely as possible with regard to certain tissue characteristics. Ideally, an identical twin is available that has identical tissue characteristics. However, this is rarely the case.

As an alternative, close relatives can be used. If there are no suitable related donors available, unrelated donors can also donate. Here, too, it applies that the tissue characteristics should match those of the recipient as closely as possible.

Several national and international databases have been set up in order to find a donor who is suitable for you. People who want to donate can register there. In Germany, 29 donor databases are currently responsible for this registration. The contact details can be found on the website of the Central Bone Marrow Donor Register Germany (ZKRD) in Ulm. All data from the donor databases come together in this central register, and this is where cooperation with the various international databases is coordinated.

Non-myeloablative stem cell transplant: fewer complications

A variant of allogeneic stem cell transplantation is the so-called dose-reduced treatment, also often referred to as non-myeloablative stem cell transplantation. This means that it is not that strong beforehand. This means that it is dosed in such a way that the recipient is not completely destroyed. The problem with this is that some of the tumor or leukemia cells remain in the body. It is hoped, however, that the donor's immune cells that are also transferred will destroy any remaining diseased cells. The non-myeloablative treatment is less stressful on the body and has a lower risk of complications. It is mainly used in people who have a very high risk of complications if the cells are completely destroyed.