This is a prospective specimen collection study evaluating the feasibility of using the ChromoSeq® assay for upfront classification in a real-time clinical setting of pediatric and young adult acute lymphoid leukemia (ALL) patients. Sixty patients will undergo collections of bone marrow and/or peripheral blood for the ChromoSeq® assay at time of initial workup, and the patients will then be followed for clinical outcomes for up to 65 months.

Eligibility Criteria

• Children and young adult patients (< 30 years of age at time of study enrollment) treated at St. Louis Children's Hospital/Washington University School of Medicine.
• Suspected diagnosis or suspected relapse of acute lymphoblastic leukemia (ALL), B- or T-cell.
• Concurrent enrollment on a prospective therapeutic trial is allowed as this protocol makes no recommendations regarding treatment approach.
• Ability to understand and willingness to sign an IRB approved written informed consent document. All patients and/or their parents or legal guardians must sign an IRB approved written informed consent document.

Child and young adult patients diagnosed with acute lymphoid leukemia (ALL) seen at St. Louis Children's Hospital/Washington University School of Medicine.

All of the individual participant data collected during the trial, after de-identification.

Immediately following publication. No end date.

Data will be uploaded to dbGaP.