Growth and Development After Hematopoietic Cell Transplantation

Pre-transplant preparative regimens including exposure to high-dose chemotherapy and total body irradiation (TBI) can lead to significant long-term consequences, particularly when these exposures occur during childhood. In children, endocrine dysfunction is a common late effect after hematopoietic cell transplantation (HCT) and can include thyroid dysfunction, thyroid malignancy, growth disturbance, and gonadal dysfunction. The most significant impact has been seen after exposure to TBI (particularly when delivered as single fraction versus fractionated doses). Myeloablative chemotherapy-only conditioning regimens such as busulfan and cyclophosphamide can also lead to endocrine dysfunction although the impact is generally less significant. After HCT, children require close follow-up and monitoring for the development of thyroid dysfunction, growth failure, and gonadal dysfunction such as delayed puberty. Appropriate interventions can ameliorate most endocrine disturbances, although some conditions such as hypothyroidism and thyroid malignancy may have a latency of decades after HCT, hence lifelong surveillance is necessary.