Bone marrow transplant - Who can have a bone marrow transplant

Bone marrow transplants are only recommended in certain situations, when other treatments have failed.

This is because there's a high risk of complications.

Bone marrow transplants are usually only recommended if:

• the recipient is in relatively good health despite their associated condition (which is why they're often carried out when cancer is in remission)
• stem cells are available from a brother/sister, or, less commonly, from another family member/unrelated donor with the same or similar tissue type (this lowers the chances of the bone marrow being rejected)
• the associated condition isn't responding to other forms of treatment, and it's believed it would respond to a transplant and could get worse without one
• the benefits of a transplant are believed to outweigh the risks

Tissue type

All human tissue carries a special genetic marker or code, known as a human leukocyte antigen (HLA).

For a transplant to be successful, the transplanted tissue should ideally come from someone with an identical or very similar HLA tissue type.

If the transplanted tissue has a different HLA type, your immune system might treat it as a foreign object and reject it.

Alternatively, the cells from the transplanted tissue may regard the rest of your body as a foreign object and start attacking it. This is known as graft versus host disease (GvHD).

Your tissue type is inherited from both parents. If you have a brother or sister who's willing to be a donor, they'll need to be tested to see whether their HLA type is the same as yours.

There's a one in four chance of each full sibling (those who share the same parents) being an exact match.

Bone marrow registry

If you're an only child, or if your siblings aren't suitable donors, a search of the NHS Blood and Transplant registry will be carried out. It holds the details of people who are willing to donate stem cells and their HLA type.

It may take several years before a suitable donor can be found. Sometimes waiting without treatment may be considered too dangerous, or finding a full match may not be possible.

In such cases, stem cells from a partially matched donor may be used. This will increase the chance of complications, but your treatment team may recommend it if the potential benefits outweigh the risks.