The goal of this clinical trial is to evaluate whether the Snoezelen multisensory relaxation approach can reduce anxiety symptoms in children and adolescents aged 8 to 17 years hospitalized for chemotherapy in a pediatric oncology unit.

Researchers will compare patients' symptoms during a chemotherapy cycle with Snoezelen sessions to a previous cycle without Snoezelen, in order to assess changes in psychological and physical well-being.

Participants will:

• Be enrolled between their first (without Snoezelen) and second (with Snoezelen) chemotherapy cycles
• Complete self-report questionnaires on anxiety, depression, quality of life, and nausea
• Receive 45-minute Snoezelen sessions every two days during their second hospitalization
• Participate in a semi-structured interview after the final session
• Provide data on medications (anxiolytics, antiemetics) and vomiting frequency during both hospitalizations

This is a monocentric proof-of-concept study using mixed methods (quantitative questionnaires and qualitative interviews) to explore the potential benefits of Snoezelen as a supportive care intervention in pediatric oncology.

The goal of this interventional study (minimal risk clinical trial - RIPH2) is to evaluate the effect of the Snoezelen multisensory relaxation approach on anxiety symptoms in children and adolescents aged 8 to 17 years who are hospitalized for chemotherapy in a pediatric oncology unit.

The primary research question is:

- Does the use of Snoezelen reduce anxiety symptoms during hospitalization for chemotherapy in pediatric cancer patients?

Secondary research questions include:

• Does Snoezelen improve quality of life and reduce depressive symptoms?
• Does Snoezelen reduce nausea and vomiting during chemotherapy? Researchers will compare participants' symptoms before and after a chemotherapy cycle with Snoezelen sessions, and contrast these with data from the previous cycle without Snoezelen.

Participants will:

• Be enrolled between their first (without Snoezelen) and second (with Snoezelen) chemotherapy cycles
• Complete self-report questionnaires assessing anxiety (GAD-7, SCARED), depression (CDI), quality of life (PedsQL), and nausea (BARF scale)
• Receive 45-minute Snoezelen sessions every two days during their second hospitalization for chemotherapy
• Participate in a semi-structured research interview after the final Snoezelen session The study will also collect data on medications administered (anxiolytics, antiemetics) and the frequency of vomiting episodes during hospitalization.

Inclusion Criteria:

• New patient
• Treated in the Paediatrics/AJA department of the Oscar Lambret Centre for cancer (all types of cancer)
• Hospitalisation for several days
• Highly emetogenic chemotherapy treatment: this corresponds to all in-patient treatments carried out in the Paediatrics/AJA department.
• Age at diagnosis : ≥ 8 years and < 18 years.
• French language
• Information for the patient and those with parental authority; consent signed by the patient and those with parental authority.
• Valid social security cover

Exclusion Criteria:

• Contraindication to SNOEZELEN:

  • Claustrophobia
  • Presence of psychiatric, addictive or cognitive disorders that would prevent compliance with the protocol requirements;

• State of health not allowing participation in the study (severe fatigue, symptoms refractory to treatment).

• Pregnant or breast-feeding women