Chemotherapy-related toxicities follow a typical pattern in children treated for acute lymphoblastic leukaemia.

Aim: Acute lymphoblastic leukaemia (ALL) therapy has been associated with a significant burden of toxicities. The aim of this study was to describe the full spectrum of toxic effects associated with childhood ALL.

Methods: Toxicity-related data were collected from the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-2008 toxicity registry, in which data on 19 clinically relevant toxicities were registered during ALL treatment, and from patient medical records. All patients treated according to the NOPHO ALL-2008 protocol in Oulu University Hospital between 2008 and 2020 were included in the study.

Results: The cohort consisted of 73 patients, 38 of whom were male. Mean age at diagnosis was 6.6 ± 4.2 (range 1.4-16.0) years. All but one of the patients developed at least one treatment-related toxicity and more than half had multiple toxicities. Female sex and older age were associated with a higher tendency towards toxicity. The most common toxicity was vincristine-induced peripheral neuropathy, which was observed in 70 patients. Most toxicities were moderate or severe, but even mild toxicities often affected leukaemia treatment.

Conclusion: Moderate and severe treatment-related toxicities are common, and most toxicities occur in a typical pattern in relation to the treatment phases.