Some patients need to have very high doses of chemotherapy (sometimes with radiotherapy). This is done to improve the chances of curing the Hodgkin lymphoma. High-dose chemotherapy may be given if standard chemotherapy has not completely got rid of your Hodgkin lymphoma. It may also be used if the lymphoma comes back after you have had standard chemotherapy. Your doctor will discuss with you whether high-dose treatment is necessary, and possible, in your case.
If you need to have high-dose treatment, you will also need to have a stem cell transplant (commonly called a peripheral blood stem cell transplant). Stem cells are the basic blood cells from which other cells develop. They can be collected directly from the blood or from the bone marrow. The bone marrow is the substance in the inner part of the bone which produces blood cells. Because high doses of chemotherapy will destroy your bone marrow, stem cells are given back to 'rescue' you from the effects of the high-dose treatment.
Although this treatment is often called a transplant, it is better described as stem cell support. This is because it is your own cells that are being collected and then returned to you. In the past, bone marrow, which contains stem cells, was often used but it is now more usual to take stem cells from the blood.
How are your stem cells collected and returned?
After chemotherapy, injections of a growth factor are given. Growth factors are proteins that make stem cells multiply and spill over from the bone marrow into the blood. The growth factor is usually given daily as a small injection under the skin (subcutaneously). You, or a relative, can be taught to do this, or a district nurse can give it. If you prefer, the injection can be given daily at the hospital.
When the number of different cells in your blood is at the right level, the stem cells will be collected. This takes about 3–4 hours and involves a drip being put into a vein in each arm. Blood is taken through the drip into a machine called a cell separator, which spins it to separate out the stem cells. These are collected and the rest of the blood is given back to you through a vein in your other arm.
The stem cells are frozen until you have had the high-dose chemotherapy. Then they are thawed out and given back into your vein by drip.
Some people may have a transplant from another person (allogeneic transplant), rather than their own cells (autologous transplant).
Stem cell and bone marrow transplants are complicated treatments and carry some risk. Because of this they are generally carried out in specialist cancer treatment hospitals. This means you may have to be treated in a hospital some distance from your home.
Anyone with Hodgkin lymphoma who has had high-dose treatment should be given blood or platelet transfusions that have been irradiated. This lowers the risk of the donated blood cells from reacting against the patient's own blood cells. Patients who have had this treatment should carry a card or wear a Medicalert so that hospital staff are aware of this in case of an emergency.
We have a section on stem cell and bone marrow transplants which gives more information on this treatment.