Study On the Recovery of Immune System After Chemotherapy in Pediatric Acute Lymphoblastic Leukemia

Acute lymphoblastic leukemia (ALL) is the most common malignancy in children. Nowadays, the cornerstone treatment of ALL is chemotherapy, which will destroy immune system at the same time of killing leukemic cells. After the cessation of chemotherapy, the immune system will rebuild gradually. Our previous study based on the BCH 93 and BCH 98 protocols showed immune system reconstruction would take 2–3 years after the cessation of chemotherapy. In recent years, the intensive chemotherapy is decreased because of accurate classification of ALL, resulting in much more proper treatment which can both cure the leukemia and reduce side effects, such as immune depression. In this study we investigate the recovery of immune system of ALL patients treated by an update CCLG-ALL-2008 protocol in Beijing Children's Hospital of Capital Medical University.

There were 104 ALL patients enrolled in this study. Their immunenoglobins (Ig) and T lymphocyte subtypes in peripheral blood were examined at the time points of 0 month, 12 months and 24 months after cessation of chemotherapy, respectively. The data was analyzed by statistical software of SPSS19.0.

Immunenoglobins of IgA, IgG, IgM and IgE were lower at the cessation of chemotherapy, and increased significantly at 12 months of stopping treatment. The IgA, IgG, IgM and IgE recovered to normal level in 61.54%, 89.23%, 90.77%, and 89.83% of ALL patients, respectively at 12 months of stopping treatment. The total B cells, T cells, CD4, CD8 and NK cells recovered to normal level in 84.85%, 92.54%, 71.64%, 67.16% and 69.23% of ALL patients, respectively at 12 months of stopping treatment. The level of immunenoglobins and T lymphocyte subtypes were no statistical differences between the time points of 12 and 24 months after cessation of chemotherapy.

Most of ALL patients rebuild their immune system within 12 months after the cessation of chemotherapy. Current protocol of CCLG- ALL-2008 based on the risk classification is more reasonable that shorten the time of immune reconstruction, compared to the results in published literatures based on our previous protocols of BCH93 and BCH 98.

Zheng:Beijing Health System High-level Technical Personel Plan: Research Funding.