[Immunization for children treated for solid tumors: what are the guidelines?]

[Article in French]

Marec-Berard P, Floret D, Schell M, Mialou V, Frappaz D, Philip T, Bergeron C.

Departement d'oncologie pediatrique, centre Leon-Berard, 28, rue Laennec, 69373 Lyon, 08, France. marec@lyon.fnclcc.fr

There is no agreement on immunization of children treated with chemotherapy (CT) for solid tumors. Based on a review of the literature, we have attempted to establish guidelines on this subject. Except for hepatitis B vaccine, there is no argument to support the use of vaccine during CT. After a standard CT, a 3-month washout period appears to be necessary before starting an immunization program for a child not previously vaccinated, or to proceed with the recommended booster injections for diphteria anatoxin, tetanus vaccine, poliomyelitis inactivated vaccine, pertussis vaccine, and haemophilus influenza type b vaccine if the child is less than 5 years old. For mumps, measles, and rubella live vaccines, a longer post-CT washout of 6 months is suggested for the initial immunization, or for a revaccination of a child proved to be negative for all three serologies. Following high-dose CT a minimal 12-months term and a normalization of the blood lymphocytes count is necessary before planning booster injections once having checked for antidiphteria, tetanic, polio, measles, mumps, rubella and +/- haemophilus antibody titles. We don't find any reason to recommend a systematic varicella immunization in pediatric oncology. Pneumococcal vaccine is recommended in case of asplenia. Any other vaccination (BCG, influenza, yellow fever) must be evaluated individually.

PMID: 11484458 [PubMed - indexed for MEDLINE]

Response to influenza immunisation during treatment for cancer.

Chisholm JC, Devine T, Charlett A, Pinkerton CR, Zambon M.

Children's Unit, Royal Marsden Hospital, Down's Rd, Sutton, Surrey SM2 5PT, UK. julia.chisholm@gosh-tr.nthames.nhs.uk

AIMS: To assess the annual risk of influenza infection in children with cancer and the immunogenicity of a trivalent split virus influenza vaccine in these children. METHODS: Eighty four children with cancer were tested for susceptibility to the circulating strains of influenza virus in autumn 1995 and 1996. Non-immunised children were reassessed the following spring for serological evidence of natural infection. Forty two patients received two doses of influenza vaccine. These children were receiving continuing chemotherapy for acute lymphoblastic leukaemia or were within six months of completing chemotherapy. RESULTS: Among the 84 children tested for influenza virus susceptibility only 8% of patients were fully protected (antibody titres >/= 40) against all three of the prevalent influenza virus strains; 33% were susceptible to all three viruses. Evidence of acquired natural infection was seen in 30% of unimmunised patients. Among immunised susceptible patients, 66% made some protective response to the vaccine and 55% showed protective antibody titres to all three viral strains following vaccination. Older age was associated with increased response to the H1N1 and H3N2 vaccine components, but total white cell count or neutrophil count at immunisation, type of cancer, or length of time on treatment for acute lymphoblastic leukaemia did not affect response. CONCLUSIONS: Most children with cancer studied were at risk of influenza infection. A significant response to immunisation was seen, supporting annual influenza vaccination for children being treated for cancer.

PMID: 11369567 [PubMed - indexed for MEDLINE]

Infections, vaccinations, and the risk of childhood leukaemia.

Dockerty JD, Skegg DC, Elwood JM, Herbison GP, Becroft DM, Lewis ME.

Childhood Cancer Research Group, University of Oxford, UK.

A nationwide case-control study was conducted in New Zealand, to test hypotheses about the role of infections in the aetiology of childhood leukaemia. Children aged 0-14 years with leukaemia were matched on age and sex to controls selected from birth records. Case ascertainment was virtually complete and 121 (92%) of 131 eligible case families took part. The participation rate among the 303 first-choice eligible controls was 69%. Home interviews and serological tests were conducted. Adjusted relative risks were estimated by logistic regression. There was an increased risk of leukaemia in relation to reported influenza infection of the child during the first year of life (adjusted odds ratio 6.8, 95% confidence interval 1.8-25.7). This could be a chance finding due to multiple comparisons, and it should be tested elsewhere. Some key variables relevant to Greaves' hypothesis were not associated with B-cell precursor acute lymphoblastic leukaemia (numbers of infections and vaccinations, firstborn status, attendance at preschool groups), although a small effect could not be ruled out with a study of this size. Leukaemia risk was higher among children in poorer social circumstances, and this was true for all eligible children as well as for the participants.

PMID: 10424755 [PubMed - indexed for MEDLINE]

[Vaccination against influenza in children with acute lymphoblastic leukemia]

[Article in Polish]

Jackowska T, Brydak L, Rokicka-Milewska R, Lukowska K, Gosk B, Rudnicka H, Regnery H, Cox N.

Katedra i Klinika Pediatrii, Hematologii i Onkologii Akademii Medycznej w Warszawie.

In November and December 1993, 49 children, ages 4 to 20, suffering from acute lymphoblastic leukemia, were vaccinated against influenza in the Department of Paediatric Haematology and Oncology, Medical Academy in Warsaw. These patients were vaccinated either in the course of maintenance treatment or after treatment. Each dose of Wyeth USA subunit trivalent influenza vaccine contained 15 micrograms of hemagglutinin of strains recommended for that season. The level of antibody production was determined in pre- and post vaccination sera in the group of children with leukemia and the control group. It was determined that in the investigated group, the GMT increased more than four times for hemagglutinins H1N1 and H3N2. A somewhat lower increase was observed in case of hemagglutinin HB. The proportion of subjects protected after vaccination was 35% for hemagglutinin H1N1, 76% for H3N2 and 100% for HB. The response rate was 33% for hemagglutinin H1N1, 47% for H3N2 and 45% for HB. In the control group the proportion of subjects protected and the response rate were very low. The results show the significant immunological efficacy of the vaccine used in the vaccination against influenza in high risk groups.

PMID: 8975216 [PubMed - indexed for MEDLINE]

Influenza immunization in immunosuppressed children.

Gross PA, Lee H, Wolff JA, Hall CB, Minnefore AB, Lazicki ME.

Optimal influenza immunization of individuals with malignancy and other immunodeficient states requires and understanding of responses to currently recommended regimens. Children with acute lymphocytic leukemia and other malignancies between three and 17 years of age were immunized with bivalent influenza vaccine containing A/New Jersey/76 and A/Victoria/75. Folowing a two-dose immunization schedule, only 37% (25468) on cancer chemotherapy seroconverted to a hemagglutination inhibition titer greater than or equal to 20 for A/NJ/76; the seroconversion rate in those not on chemotherapy was 92% (68/74, P less than 0.001). The immune response to the A/Vic/75 antigen was also related to a history of recent chemotherapy. There was no correlation between the immune response and the peripheral white blood cell count except at counts less than or equal to 1,000. The optimum time to immunize children with malignancies is when they have been off chemotherapy for one month and have peripheral white blood counts greater than 1,000.

PMID: 619076 [PubMed - indexed for MEDLINE]

Antibody responses to influenza immunization of children with acute lymphoblastic leukemia.

Lange B, Shapiro SA, Waldman MT, Proctor E, Arbeter A.

Antibody responses of two doses of a bivalent influenza vaccine containing A/Victoria/75 (A/Vic/75) and A/New Jersey/76 (A/NJ/76) viral antigens were studied in 22 children receiving maintenance chemotherapy for acute lymphoblastic leukemia (ALL), 16 children no longer receiving therapy for ALL, and 50 sibling controls. Before immunization, the three groups showed no difference in titer of antibody to either antigen. After the first immunization, children off therapy showed significantly higher titers to A/NJ/76 than did either sibling controls of children receiving therapy (P less than 0.01). After the second immunization, children off therapy showed significantly higher antibody titers to both antigens than did children receiving therapy or controls (P less than 0.01 for both A/NJ/76 and A/Vic/75). Antibody titers of children receiving therapy were not significantly different from those of controls. A year later, there were no significant differences in antibody titers among the groups. Thus, children with ALL who are receiving chemotherapy respond normally to two doses of influenza vaccine, whereas children off therapy manifest abnormally high titers of antibody to both influenza virus antigens.

PMID: 291662 [PubMed - indexed for MEDLINE]