Lack of Consensus on Humoral Immune Status Among Survivors of Pediatric Hematological Malignancies: An Integrative Review

Leukemias and lymphomas account for more than half of new cancer cases in children each year. As a result of advancements in clinical protocols, survival rates for hematological malignancies in children now approximately 80% to 90%. The short-term effects of chemotherapy are well documented; however, many late effects remain unclear, notably those on the humoral immune system. The recent resistance toward childhood vaccination in some communities in conjunction with a growing number of potentially underprotected survivors could place this population at increased risk for common communicable diseases. Additionally, survivors could serve as a significant reservoir for further spread of disease within the general population. The state of the scientific knowledge regarding humoral immunity in this population is insufficient for concrete conclusions. An intensive search of the literature on various platforms was performed to identify articles reporting on the rates of protection to common vaccine-preventable diseases in survivors of pediatric hematological malignancies. Articles were selected with respect to inclusion and exclusion criteria. Quality was evaluated against specific methodological standards. Each study shows evidence that participants were lacking immunity to at least one vaccination following treatment. A majority of participants recovered immunity after revaccination, with a small percentage remaining unprotected. There is no consistency between studies regarding the rates at which immunity is present; furthermore, there are no particulars on how long immunity persists following revaccination. Vaccination represents an instrumental public health initiative for reducing morbidity and mortality globally. The clinical ramifications of losing protection against vaccine preventable diseases are therefore serious.