Feasibility, uptake, and exploratory outcomes of an individualized exercise program in pediatric oncology: a prospective single-center pilot study.

INTRODUCTION: Exercise interventions may help mitigate treatment-related physical impairment in pediatric oncology, but implementation in routine care remains challenging, particularly during active treatment and in heterogeneous patient cohorts. PATIENTS: This prospective single-center pilot study evaluated an individualized exercise program for children and adolescents aged 4-17 years undergoing cancer treatment during the COVID-19 pandemic. METHOD: The program combined supervised in-hospital exercise, personalized home-based training, and an optional video-based SMART-Sport component introduced from month 3. The primary focus was feasibility, uptake, safety, and acceptability. Motor performance, six-minute walk distance, health-related quality of life (HRQoL), and neuropsychological functioning were assessed at baseline and six months as secondary exploratory outcomes. RESULTS: Twenty participants were enrolled; 15 completed at least one six-month follow-up assessment. Overall, 348 of 583 scheduled in-hospital exercise opportunities were attended, corresponding to a scheduled-session attendance of 59.7% using a conservative denominator. No serious program-related adverse event occurred. Movement diaries were available for 15 participants and documented 361 home-training sessions, of which 262 (72.6%) occurred during the first three months. Four participants documented use of SMART-Sport, completing 14 sessions. Exploratory complete-case analyses showed nominal within-participant improvements in hand-eye coordination, reaction time, six-minute walk distance, and selected HRQoL domains. Neuropsychological findings were inconclusive. DISCUSSION: The findings support the feasibility and safety of supervised individualized in-hospital exercise under the conditions of a specialized pediatric oncology center with a dedicated sports therapist. Feasibility was component-specific: home-training documentation decreased over time, and uptake of the optional video-based component was limited. CONCLUSION: This pilot study provides preliminary implementation data supporting further development of individualized exercise programs in pediatric oncology. Exploratory outcome findings should be interpreted as hypothesis-generating and require confirmation in larger controlled studies.