Bone marrow and stem cell transplantation are among the newest treatment options for lymphoma patients, especially those who have relapsed.

Bone marrow is the soft, spongy material found in the channels located in the middle of your bones. This is where the body manufactures your blood cells. In adults, the majority of bone marrow is produced in the bones of the hip, chest, back, skull, upper arms, and legs.

Stem cells are cells that are not yet mature. As they mature, they become whatever kind of blood cells your body needs, ie, white cells, red cells, and platelets. They are found mainly in the bone marrow, but can also be found circulating in the blood.

The reason to have a transplant is so that doctors can administer a very high dose of chemotherapy or radiation. Normally this dose would destroy the bone marrow. Using a transplant following high-dose treatment allows doctors to infuse stem cells or bone marrow to rebuild the bone marrow.

High-dose treatment and transplantation require several weeks or months of closely coordinated care. Patients stay in the hospital for a period of time, usually a few weeks. There are four main steps to a transplant.

• Harvesting the marrow or stem cells - In recent years, stem cells have been harvested from the blood, after treatment with chemotherapy and GCSF (a blood stimulant), with the blood being returned to the patient immediately.
• Processing or preserving the marrow or stem cells - Stem cells are concentrated by the use of antibodies, then are frozen and stored.
• Administering therapy - This is usually high dose chemotherapy, sometimes combined with radiation, to eliminate the most resistant cancer cells. But this high dose treatment also wipes out healthy blood and lymph cells. The type of chemotherapy will depend on the stage of the disease, whether it is a recurrence, the condition of the patient, and the treatment facility's preferences and experience.
• Reinfusion of the harvested cells or bone marrow - As the harvested stem cells or marrow are returned to your body (transplanted), they travel through the circulatory system to the bone marrow to implant themselves and begin production of new healthy cells. In time, the marrow produces a sufficient number of healthy cells to completely populate the blood and lymph system.