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Total lymphatic irradiation


Total lymphatic irradiation (TLI) is an important part of some progenitor cell transplants. (Progenitor cells are blood making cells in the bone marrow and peripheral blood.) TLI is part of getting your child’s body ready for the new, healthy donor cells. Chemotherapy and TLI are used together to prepare for the transplant. Your child might have TLI before, during, or after chemotherapy.

What is TLI?

TLI is a form of radiation therapy. Radiation therapy treats disease with high-energy waves, like strong X-rays. TLI is radiation given to your child’s lymphatic system. The lymphatic system makes cells for your child’s immune system. Normally, having a strong lymphatic system is good, but it can kill the new, healthy donor cells your child gets in a transplant. TLI helps turn off your child’s immune system for a short time, so it will not harm the new cells.

total lymphatic irradiation

In this drawing, the area inside the gray lines shows what parts of the body will receive this radiation therapy.

How is TLI given?

TLI is given in 4 doses. Your child might get it twice a day for 2 days or twice on day 1 and one time on day 2 and day 3. Your child’s doctor and the St. Jude staff will tell you your child’s TLI schedule and answer any questions you have.

Your child’s TLI schedule: _______________________________________________________

Getting ready for TLI

You and your child will go to Radiation Oncology about a week before TLI. You will meet doctors, nurses, and radiation therapists. The radiation therapists are the people who will give your child’s TLI treatments. The staff will show you and your child how TLI is given, talk with you about possible side effects and answer your questions. They will ask you to sign a consent form (a form that gives permission for your child to have TLI).

Your child might have an appointment called a “simulation visit” on the same day you learn about TLI. A simulation visit gets your child ready for the treatments.

Your child’s simulation visit

The Radiation Oncology staff makes a plastic “mesh mask” and a device called “mold care” to help your child stay in position during treatment.

After your child has a mask and a mold care device made, he will have a CT scan in the treatment position. A CT scan uses X-rays to create pictures of the inside of the body. The pictures from your child’s CT scan will help the staff plan the TLI treatment.

During the simulation visit, your child will probably get some small permanent dots, like tattoos, to help mark the correct position for treatment. The dots are about the size of a pencil tip, and they will not cause problems with any other treatments your child needs. The radiation therapist might also draw some lines on your child’s body with a paint marker. These are not permanent but help mark the correct treatment position. Please do not wash off these marks until your child is done with treatment.

Your child’s simulation visit is ___________________________________________________________

What is TLI like?

Your child will be asked to lie on his back in the mask and the mold care device while the radiation therapist gives the treatment. Your child should relax, stay as still as possible and breathe normally. The radiation beam cannot be felt, but the treatment machine might make noises your child can hear.

No one can be in the treatment room during therapy, but the radiation therapist will watch your child on the TV monitor and can always hear your child. If your child is sedated during treatment, the sedation doctor and nurse will watch over him during treatment.

Your child can listen to music or audio books during the treatment. You can bring your child’s music or make a playlist for the treatment room’s iPod.

After the treatment is over, your child can go back to his hospital room. There is no radiation in your child’s body after the machine is turned off, and your child is not radioactive.

What are the side effects of TLI?

Your child might have some of the side effects listed below, or he might not have any. The doctor will talk with you about side effects before treatment starts, and answer any questions you have. Most side effects go away after treatment is over.

Side effects are called “early” or “late,” depending on when they happen after the start of treatment.

Possible early side effects of TLI

Early side effects can happen shortly after the start of TLI and up to 6 months afterward. They include:

  • Nausea and vomiting,
  • Diarrhea,
  • Loss of appetite,
  • Skin redness,
  • Dry skin,
  • Fatigue (feeling very tired), and
  • Hair loss in the treated area.

Possible late side effects of TLI

Late side effects can happen 6 months or longer after TLI. They can include:

  • Changes in normal growth and development,
  • Having fewer than normal of certain types of blood cells,
  • Changes in the function of the heart, lungs, liver, and kidneys,
  • Hormone problems,
  • Trouble getting pregnant or fathering a child, and
  • Other cancers.


To learn more about TLI and your child’s treatment, talk to a Radiation Oncology nurse or call 901-595-3655.


This document is not intended to take the place of the care and attention of your personal physician or other professional medical services. Our aim is to promote active participation in your care and treatment by providing information and education. Questions about individual health concerns or specific treatment options should be discussed with your physician.

St. Jude complies with health care-related federal civil rights laws and does not discriminate on the basis of race, color, national origin, age, disability, or sex.

ATTENTION: If you speak another language, assistance services, free of charge, are available to you. Call 1-866-278-5833 (TTY: 1-901-595-1040).

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