Preoperative short-term fasting in paediatric cancer care is safe, feasible and activates protective responses

Background: Paediatric cancer patients often face treatment-induced complications significantly affecting Quality of Life. Short-term fasting (STF) could mitigate therapy-related adverse toxicity by triggering a protective survival response. While STF and other nutritional interventions have shown clinical benefits in adults, application in paediatric cancer remains unexplored. This study aims to explore the safety and feasibility of incorporating STF into the treatment regimen for children with renal cancer, while simultaneously showing a protective transcriptomic signature. Methods: Here we selected children with a localized renal tumour at the Princess Máxima Center. In a randomized controlled setting preceding surgery (FIURTT-study), these children fasted for 10–18 h, depending on age, during which patient/parent experiences and blood measurements were collected. To investigate the STF-induced effects on enhancing postoperative recovery, kidney tissue was used for transcriptome analysis, and compared to a well-defined 2.5-day fasting response in adults. Results: Blood measurements of 13 patients revealed significantly decreased glucose levels after STF, without occurrence of hypoglycaemia. Questionnaires demonstrated that patients and parents experienced no obvious burden and described the intervention as highly feasible. RNA-expression patterns in normal kidney tissue unveiled distinctions between cases with STF and those without, displaying significant difference in relevant pathways linked to activated protective-responses, resembling those in adults. Conclusion: Our results indicate pre-operative STF to be safe and feasible in children with cancer. Also, we observed induction of the survival response at the transcriptional level, suggesting that STF induced a protective gene expression profile already after relatively short fasting periods.