Acute lymphoblastic leukaemia/lymphoma (ALL/LBL) and its treatment interfere with normal physical functioning. However, it remains unclear how physical fitness (PF) is affected throughout treatment for ALL/LBL. Sixty-two patients (2.1 to 18.3 years) treated for ALL/LBL underwent four physical tests at nine timepoints from baseline up to 6 months post-treatment. We assessed muscle strength of the quadriceps and tibialis anterior, standing broad jump test (SBJ) for functional mobility and six-minute walk test (6MWT) for endurance. One-sample t-tests were used to compare our results to the norm at each timepoint. Norm-referenced Z-scores were predicted based on time, risk group and age at diagnosis, using linear mixed models. Quadriceps strength, SBJ and 6MWT scores were significantly lower than norm values at all timepoints from diagnosis up to 6 months after maintenance therapy. Significant decreases over time were encountered for quadriceps strength and SBJ, mainly occurring after induction therapy (F = 3.568, p < 0.001 and F = 2.699, p = 0.008, respectively). Age at diagnosis was a significant predictor for tibialis anterior strength (F = 5.266, p = 0.025), SBJ (F = 70.422, p < 0.001) and 6MWT (F = 15.890, p < 0.001) performances, with lower results in adolescents at all timepoints. Six months after treatment, quadriceps strength, 6MWT and SBJ scores remained below expected levels.
Conclusion: The decreased quadriceps strength, functional mobility and endurance at all timepoints, with a large deterioration following induction therapy, suggest the need for early interventions, specifically in the adolescent population. The continued low results 6 months after therapy emphasise the importance of long-term rehabilitation.
What is known: •Acute lymphoblastic leukaemia is the most common type of cancer among children, with increasing survival rates due to therapeutic improvements. •Acute lymphoblastic leukaemia/lymphoma and its treatment can cause muscle weakness, neuromuscular toxicity and a decreased cardiopulmonary fitness. Together with physical inactivity, this can result in a decreased physical fitness.
What is new: •Quadriceps strength, functional mobility and endurance are decreased during treatment for acute lymphoblastic leukaemia/lymphoma. The lowest measurements are observed after induction therapy, suggesting the need for early interventions. •We observed continued lower results for quadriceps strength, functional mobility and endurance at the end of treatment, up to 6 months after therapy, supporting the need for long-term rehabilitation.
Keywords: Acute lymphoblastic leukaemia; Endurance; Functional mobility; Lymphoblastic lymphoma; Muscle strength; Physical fitness.
© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.