Inclusion Criteria:

* Patient must have been diagnosed with CML-CP at < 18 years of age.
* Patient must have histologic verification of CML-CP at original diagnosis
* Patient must be in molecular remission (MR) with a BCR-ABL1 level of =< 0.01% BCR-ABL1 as measured using the International Scale (IS) by RQ-PCR for >= 2 consecutive years at the time of enrollment

* Please note: The lab evaluating disease status and molecular response for this study must be College of American Pathology (CAP) and/or Clinical Laboratory Improvement Amendments (CLIA) certified (United States \[US\] only), sites in other countries must be certified by their accredited authorities. All labs must use the International Scale guidelines with a sensitivity of detection assay =< 0.01% BCR-ABL1 and be able to report results in =< 2 weeks
* Patient must have received any TKI for a minimum of 3 consecutive years at time of enrollment
* Patient agrees to discontinue TKI therapy
* REGULATORY REQUIREMENTS
* All patients and/or their parents or legal guardians must sign a written informed consent
* All institutional, Food and Drug Administration (FDA), and National Cancer Institute (NCI) requirements for human studies must be met
* ELIGIBILITY FOR PATIENT-REPORTED OUTCOMES (PROs):
* Age >= 8 years at the time of enrollment
* Ability to understand English or Spanish
* Cognitive ability to complete instruments according to the primary team
* ELIGIBILITY FOR AAML18P1 NEUROCOGNITIVE STUDY:
* Patient must be 5 years or older at the time of enrollment
* English-, French- or Spanish-speaking
* No known history of neurodevelopmental disorder prior to diagnosis of CML (e.g., Down syndrome, Fragile X, William syndrome, mental retardation)
* No significant visual or motor impairment that would prevent computer use or recognition of visual test stimuli

Exclusion Criteria:

* Known T3151 mutation
* Additional clonal chromosomal abnormalities in Philadelphia chromosome (Ph) positive (+) cells at any time prior to enrollment that include "major route" abnormalities (second Ph, trisomy 8, isochromosome 17q, trisomy 19), complex karyotype or abnormalities of 3q26.2
* History of accelerated phase or blast crisis CML
* Female patients who are pregnant
* Lactating females are not eligible unless they have agreed not to breastfeed their infants
* Female patients of childbearing potential are not eligible unless a negative pregnancy test result has been obtained