Background All healthcare professionals working with children should have a child-centred perspective, and should be responsive to children and adolescents who want to talk about their thoughts and feelings. The child's or adolescent's story is the starting point for mutual understanding between them and the healthcare professional, and is the basis for shared decision-making between patients and healthcare professionals in child-centred care.

Aim To advance understanding of how Swedish children and adolescents with cancer perceived the effects of the disease and its treatment on their everyday life.

Method Ten girls and five boys, aged between five and 18 years, with cancer were interviewed individually using four communication tools. The interviews lasted between 20 and 65 minutes and took place without their parents present. The data were analysed using content analysis.

Findings Transition to an unpredictable everyday life was identified as a main theme, with five subthemes: struggling with side effects of the cancer and its treatment; treatment as an 'emotional rollercoaster'; changed self and being vulnerable; changed social life; and concerns about academic achievement.

Conclusion To provide effective support and care for children and adolescents with cancer, healthcare professionals should strive to listen to them and focus on their perspectives.