The search for genetic alterations in primary tumor by NGS techniques followed by the detection of these alterations in circulating tumor DNA and/or CTC/DTC present in peripheral samples (blood, cerebrospinal fluid, bone marrow, possibly urine) collected during several steps and after the treatment could be a tool to monitor the response during and after the treatment.

Inclusion Criteria:

• Children with metastatic and/or high risk solid tumor, of the following pathologies :

Neuroblastoma, sarcoma, malignant brain tumor (medulloblastoma, high-grade glioma), bone tumors, rhabdoid tumors, others rare tumors

• Availability of a frozen tumoral sample (primary tumor or metastasis whatever the localization) at diagnosis allowing analysis of genetic alterations by a NGS technique
• Age < 18 years
• Signed informed consent by parents or legal representatives
• Patient having health care insurance

Exclusion Criteria :

• Age ≥ 18 years
• No signed informed consent by parents or legal representatives

Sponsor will share de-identified data sets. Documents generated under the project will be disseminated in accordance with Institut Curie policies.

Data requests can be submitted starting 9 months after last article publication and will be made accessible for up to 12 months.

Access to trial individual participant data can be requested by qualified researchers engaging in independent scientific research, and will be provided following review and approval of a research proposal and Statistical Analysis Plan (SAP) and execution of a data sharing agreement (DSA).