Growth hormone therapy after hematopoietic cell transplantation in childhood: a nationwide survey and longitudinal cohort study.

BACKGROUND

Growth impairment is a major late effect in survivors of childhood hematopoietic cell transplantation (HCT); however, the long-term effectiveness and response patterns of growth hormone (GH) therapy after HCT remain unclear. Thus, this study aimed to evaluate the effectiveness of GH therapy and clinical factors associated with GH response in patients who underwent HCT during childhood and were diagnosed with short stature and to further examine long-term response patterns among those receiving GH therapy.

METHODS

We conducted a nationwide, multicenter retrospective cohort study of childhood HCT survivors with post-transplant short stature. Height outcomes were evaluated using final adult height standard deviation scores (SDS) and changes in SDS (ΔSDS). Factors associated with height outcomes and GH responsiveness were analyzed using multivariable regression models, and longitudinal growth trajectories after GH initiation were assessed at 1 year, 5 years, and final height.

RESULTS

Among 171 patients with available final height data, 58 received GH therapy. GH-treated patients showed significantly greater improvement in final height SDS and ΔSDS than untreated patients, although growth responses were heterogeneous. Total body irradiation (TBI), HCT before 5 years of age, and chronic graft-versus-host disease were independently associated with poorer height outcomes. Factors associated with GH responsiveness differed by transplant type: absence of TBI and female sex were favorable in allogeneic HCT. Regarding complications, GH therapy was not associated with an increased risk of slipped capital femoral epiphysis, secondary malignancies, or relapse of the primary disease.

CONCLUSIONS

GH therapy improves height outcomes after childhood HCT, but responses vary and are strongly influenced by transplant-related toxicity and long-term complications. To improve height outcomes, optimizing GH therapy and developing strategies for patients expected to respond poorly remain important challenges.