The chemotherapy, radiation and/or immunotherapy you receive in the days leading up to your transplant is called a preparative regimen. TBI is used as part of a preparative regimen before stem cell or bone marrow transplantation to help prepare the body for transplant and destroy residual cancer cells. Doses and delivery are tailored to each patient’s medical condition and overall treatment plan.

TBI gives a dose of radiation to the whole body. It can destroy cancer cells throughout the body. It also diminishes the immune system so that it will not attack the donor's cells during the transplant.

TBI can reach cancer cells within tissue or other areas of the body that chemotherapy may not reach (due to a blood/brain barrier, for example). However, the dose of radiation must be low enough that the body's healthy cells can recover. For this reason, TBI alone cannot be used to destroy large numbers of cancer cells. Instead, the transplant preparative regimen uses TBI along with high-dose chemotherapy. Some preparative regimens use only chemotherapy and do not include TBI.

Next step: Schedule a consultation with a Northwestern Medicine radiation oncologist specializing in transplant preparatory regimens.

To learn more, visit radiation oncology.