Abnormalities of the immune system in children with neuroblastoma related to the neoplasm and chemotherapy.

Children with localized and metastatic neuroblastoma were studies to determine their immune status at the time of diagnosis and while they were receiving intensive intermittent chemotherapy; Investigations included leukocyte and differential counts, delayed hypersensitivity response, quantitative serum immunoglobulins, percentages of T and Fc receptor lymphocytes, PHA-induced mitogenesis, and antibody-and PHA-dependent cellular cytoxicity. Abnormalities related to the neoplasm at diagnosis were limited to depressed leukocyte and lymphocyte counts and increased concentrations of serum IgM in patients with metastases to bone marrow and other sites. No abnormalities were observed in those with localized tumors. Intermittent chemotherapy of metastatic neuroblastoma caused immunosuppression. Effects were most marked during five-day courses of chemotherapy; they included abrogation of DH and decreased leukocyte and lymphocyte counts and percentages of Fc receptor lymphocytes. Recovery of DH with partial recovery of leukocyte and lymphocyte counts was observed three weeks, later, prior to the next course, We conclude that both metastatic tumor and chemotherapy cause abnormalities of the immune system in children with neuroblastoma.