Children's Health Ireland says its aware the impact delaying chemotherapy treatment for sick children has on them and their families.
A number of young patients have had their admissions pushed back due to the increase in numbers presenting at emergency departments with the flu and winter vomiting bug.
CHI has contacted the families affected to reschedule the appointments and it says these will be arranged for as soon as possible.
Donal Buggy from the Irish Cancer Society says delaying appointments has a big impact on families.
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