MoleculAr Profiling for Pediatric and Young Adult Cancer Treatment Stratification 2

Inclusion Criteria: * Patient referred for sequencing of the tumor within the FMG2025 or equivalent program and written consent for FMG2025 - Cancers et leucémies pédiatriques en échec de traitement or equivalent signed * Written informed consent for MAPPYACTS 2 (or non-opposition for retrospective clinical data collection) according to local or national regulations * Patient with confirmed solid tumor or leukemia which is relapsed or refractory to standard treatment and who is potentially eligible for an experimental treatment or an early phase clinical trial at the time of tumor sequencing * Planned tumor biopsy, surgical resection, bone marrow or blood sample or recently (possibly within the last 3 months) archived frozen tumor material available of the current recurrent or refractory disease * Patients aged ≤ 25 years at the time of initial diagnosis * Performance status and life expectancy \> 3 months at the time of tumor sequencing that allows enrolment into an experimental trial * Patients affiliated with a Social Security Regimen or beneficiary of the same as per local regulatory requirements Exclusion Criteria: * Any concurrent illness or laboratory abnormality that, in the opinion of the investigator, is likely to interfere with the interpretation of study results * Pregnant women