Childhood Cancer

Bone marrow, the spongy material that fills the long bones in the body, is a blood-forming tissue. It produces white blood cells (which fight infection and disease), red cells (which carry oxygen and nutrients to body tissues), and platelets (which help form clots to stop bleeding). Decreases in cell production can cause lowered immune function, anemia, or bleeding problems.

Organ damage

Radiation to the bone marrow can affect blood cell production long after treatment ends. The amount of damage depends on the radiation dose and the amount of bone marrow in the radiation field.

Chemotherapy can also cause long-term effects in bone marrow function. Although the blood counts of most survivors return to normal within weeks after therapy ends, a few survivors treated with chemotherapy have problems with low blood counts for years after treatment.

My daughter was on a high-risk protocol for ALL (acute lymphoblastic leukemia). She went off treatment over 5 years ago. She had a CBC (complete blood count) 1 month after treatment ended, and all her counts were normal. They have stayed normal ever since. She rarely gets sick: I can’t remember the last cold she had. In fact, we almost never see the pediatrician anymore because she just has her yearly follow-up visits with the late-effects oncologist.

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My daughter was diagnosed with average-risk ALL when she was 7 years old. She was treated with chemotherapy only. She has been off treatment over 2 years and her blood counts have never returned to normal. She had a CBC before she got sick, so we have a baseline. On that test, her platelets were 450,000. Since her treatment ended, they have never gone over 100,000. Her white blood cell count stays around 3.0 and her ANC (absolute neutrophil count) fluctuates between 600 and 1200. Her hematocrit is okay at around 38.

She catches every bug that goes around and has a hard time getting over them. For instance, last winter she got the flu and was sick for 4 weeks. She gets a lot of colds and they last 2 weeks. She has never regained her energy. She used to go out and ride her bike in the neighborhood for 2 or 3 hours. Now she can only manage a block or two before she comes back in and lies down. The doctors kept saying it takes some kids’ immune systems longer to bounce back than others, but on our last visit the oncologist said, “I don’t think it’s ever going to come back.”

Children who have undergone a stem cell transplant have lowered immune system function for months after treatment. The bone marrow of these children has been destroyed by chemotherapy and/or radiation to allow the healthy marrow or stem cells to grow. Re-establishing the immune function takes time. All stem cell transplant recipients have profound impairment of the immune system for up to a year. Transplant teams give families specific instructions about ways to prevent infections during that time.

Our daughter (age 9) had a peripheral blood stem cell transplant to treat her Ewing’s sarcoma. It’s been several months and her white blood cell count is still low, but we have come to the conclusion that we can’t make her live in a bubble anymore. We are careful to avoid potential risks, though, such as being around large crowds of people.

Graft-versus-host disease (GVHD) is a frequent complication of allogeneic stem cell transplants (when stem cells come from a donor). It does not occur with autologous (when stem cells come from the patient) or syngeneic transplants (when stem cells come from the patient’s identical twin). In GVHD, the bone marrow or stem cells provided by the donor (graft) attack the tissues and organs of the child receiving the transplant (host). There are two types of GVHD: acute GVHD and chronic GVHD. Acute GVHD occurs within the first 100 days and chronic GVHD occurs or persists after day 100. Patients can develop one type, both types, or neither one. Approximately 30 to 50 percent of survivors who have a related human leukocyte antigens (HLA)-matched transplant develop some degree of GVHD. The incidence and severity of GVHD are increased for children or teens who receive unrelated or mismatched marrow, but are decreased if cells that cause GVHD are reduced prior to infusion. The majority of GVHD cases are mild, although some can be life-threatening.

JaNette’s transplant was on May 5 and her ANC was up to 1000 on May 30. That’s when her graft-versus-host started. It doesn’t look like a regular rash, more like pinpoint red dots under the skin. It’s very itchy, and then it starts to peel. She looked like she had leprosy! She had very little internal graft-versus-host disease. She’s a year and a half post-transplant, and she still broke out in a rash the last time they tried to taper her off the cyclosporine.

Chronic GVHD delays the return of normal immune function. Even when survivors with chronic GVHD have normal numbers of T and B cells, they may still be at risk for infection. Up to one-third of survivors with chronic GVHD develop serious, life-threatening infections. 4

Signs and symptoms of GVHD

GVHD primarily affects the following parts of the body:

  • Skin (itchy rash, discoloration or tightening of the skin, hair loss)

  • Eyes (dryness, light sensitivity)

  • Mouth and esophagus (dryness, tooth decay, difficulty swallowing)

  • Intestines (diarrhea, cramping, weight loss)

  • Liver (jaundice)

  • Lungs (shortness of breath, wheezing, coughing)

  • Joints (decreased mobility)

  • Delayed immune response

Children or teens who underwent autologous stem cell transplants do not develop GVHD, but they can have a delayed immune response. The signs and symptoms of infection are fevers, sore throat, and shortness of breath, often accompanied by fatigue. However, fatigue by itself is not a symptom of infection. In addition, chicken pox and/or shingles can pose a threat to life if they are contracted when a child or teen is immunosuppressed.

Yossi had a small pimple near his eye on day 517 after his allogeneic BMT. The doctor thought it was a sty, and we put in antibiotic drops and started him on warm compresses. But by that afternoon, it had spread all around the bottom of his eye, near his nose and his lip. All on his left side. It was shingles. He went in the hospital for IV (intravenous) acyclovir for several days, then came home. After a few days the left side of his face looked pretty bad, but it stopped hurting and itching. He jokes that he is “Two Face.”

Screening and detection

Survivors of stem cell transplantations receive a multitude of tests that evaluate immune system function. Your institution will have its own list of tests and schedules, but it should include tests for both immune function and GVHD.

Medical management (after transplant)

Stem cell transplant survivors with GVHD may be treated with corticosteroids and other medications. All stem cell transplant survivors get prophylactic antibiotics for at least 6 to 12 months, and those with chronic GVHD continue to take antibiotics until all GVHD therapy has ended. If the survivor has low levels of IgG, she may get monthly IV IgG until her serum levels are normal for 2 months.

Prior immunizations are no longer effective after stem cell transplantation. Each treating institution has its own schedule for re-immunizing children and teens. Generally, survivors with no GVHD are given inactivated polio, influenza, and DPT (diphtheria-pertussis-tetanus) immunization after the first year. The MMR (measles-mumps-rubella) vaccine is usually given after the second year (survivors with GVHD do not receive the MMR). Find out when you (or your child) should get each immunization and talk with a healthcare provider about ways to avoid exposure to diseases until you are fully immunized. You also need to know how the treating institution manages chicken pox and shingles after a transplant.

Medical management (after treatment for any cancer)

Children who were treated when very young often miss immunizations and need to get them after treatment ends and their immune systems return to normal. Different institutions have different recommended schedules for re-immunizations. For example, your survivorship program may ask about immunization status and, if any are missing, advise that your child’s pediatrician update them based on the Centers for Disease Control and Prevention (CDC) immunization schedules (see ). The U.S. guidelines recommend re-immunization no sooner than 3 months after standard chemotherapy and no sooner than 12 months after a stem cell transplant. 5 Both girls and boys are advised to receive the human papillomavirus (HPV) vaccine based on current recommendations. 6 Parents should check with their child’s treating institution to find out the preferred immunization schedule for their child.

In addition, chemotherapy and radiation used to treat any childhood cancer can render prior immunizations ineffective. Recent studies in the United Kingdom have supported a strategy of re-immunizing all children after chemotherapy or stem cell transplantation, although a small number of patients do not achieve protective antibody levels after re-immunization. 5 More research is needed to better understand whether patients should be screened for antibodies against vaccine antigens (meaning whether immunizations given prior to treatment are still effective). 7

My 13-year-old son Lucas was treated with surgery, chemotherapy, and radiation for Wilms tumor when he was 1 year old. I read a study about how chemotherapy can wipe out previous immunizations, so last year I had the oncologist check Lucas’ titers. They were drawing blood anyway, so they just added that to the form. The results came back and, sure enough, Lucas needed to be re-immunized for about half of his vaccinations (even though everything was done on schedule and even though we waited over a year for him to be off treatment to get other vaccines and followed the schedule after that for years). So he’s 12 years old and I’m thinking that he’s “protected” because I’ve done everything we were supposed to do for vaccines, and it turns out that he wasn’t as protected as I thought he was. A few other parents I know have done it now, as well. Some of their kids were fine, but a few had also had low or non-existent immunity to illnesses for which they had been vaccinated.

I am not saying one way or another that any parent has to or should get their child vaccinated. All I am saying is that for those parents who have had their child vaccinated and the child has undergone chemotherapy, it might be a good idea a couple of years off treatment to get their titers checked (during routine blood work) to make sure the child is still protected or needs to be re-immunized.