Children with cancer undergo intensive treatment with many serious side effects and frequent in- and outpatient visits. Studies show that the frequent hospitalizations are very disruptive to children and their families, who strive to maintain a normal everyday life. The aim of the study is to test a parent-led home-administered low-dose cytarabine intervention that will not compromise the quality of treatment and care, increase the caregiver burden or the experienced symptoms of the children. The methodical approach is based on The Medical Research Council's framework to develop and evaluate complex interventions in health care using both clinical observational methods, participatory methods, surveys and qualitative ethnographic methods. The overall goal of the project is to support and ease the everyday lives of children with cancer and their families during the intensive treatment periods.

This single-arm feasibility study is conducted at Copenhagen University Hospital, Rigshospitalet, in Denmark at the Department of Pediatric Oncology and Hematology.The PI started to recruit participants March 2022. Patients with Acute Lymphoblastic Leukemia (ALL), Philadelphia positive Acute Lymphoblastic Leukemia (PH+ALL) and Lymphoblastic Lymphoma (LBL) are eligible for inclusion if their parents speak and understand Danish or English, able to manage basic treatment and care such as oral medication, mobilization, nutrition, central venous catheter care and practice good personal hygiene. The parents' competences are assessed by the PI in collaboration with a team of project- and ward nurses who know them. Participants are recruited between day 15 and 29 from diagnosis. Parents to eligible participants and adolescents aged 15+ receive oral and written information and provide written informed consent before inclusion. Children and adolescents less than 15 years of age receive oral information and provide oral consent if possible according to their age. Parents to the included participants are offered to administer the protocolized low-dose bolus (injection) Cytarabine in their children's CVCs at home. The administration procedure is developed as a simple and safe non-touch technique. The parents receive a video and paper-based guideline and information material followed by a 3-step nurse-led education program. The parents can administer the Cytarabine at home when they (and the child/adolescent) feel safe and comfortable managing the procedure and when the nurses are sure that the parents can manage the procedure at home. The first dose of Cytarabine is always administered at the hospital.

Inclusion Criteria:

- Children/adolescents diagnosed with ALL, LBL or PH+ ALL

Exclusion Criteria:

• If their parents did not understand, read and speak Danish
• If the parents did not manage the children/adolescents' basic care and treatment needs (CVC care, oral medication, hygiene, nutrition, mobilization, ect.)