A Study About How Blood Cell Growth Patterns Relate to Heart Health After Treatment for Hodgkin Lymphoma

Inclusion Criteria:

* Patient must be \>= 7 years of age at the time of enrollment (age to perform an MRI without sedation).
* History of pathologically confirmed classical Hodgkin Lymphoma (cHL) initially diagnosed when the patient was \>= 2 and \< 22 years of age.
* As part of frontline therapy for cHL, the patient must have received a cumulative doxorubicin equivalent anthracycline dose of ≥ 200 mg/m\^2 as estimated in doxorubicin isotoxic equivalents dose conversion calculation.

  * Note: History of COG therapeutic trial participation is not required. Institutional records (e.g., clinic note, treatment summary, chemotherapy roadmap) can be used as reference documentation of receipt of anthracycline dose.
* All systemic cancer treatment must have been completed ≥ 2 years prior to study enrollment.
* Not known to have had a primary event (relapse/second malignancy/death).

  * Note: Subjects treated at another institution are eligible if they are now being followed at the current COG institution, if the study procedures can be performed and the data accessible by a COG institution where the study is open.
* Patient must have access to cardiac MRI at the enrolling institution and must be able to complete cardiac MRI without sedation.

Exclusion Criteria:

* Medical contraindication to undergoing a non-contrast cardiac MRI.
* Patients with nodular lymphocyte-predominant HL.
* Received cancer therapy in addition to that for primary Hodgkin Disease (e.g., for disease progression or recurrence, or subsequent malignant neoplasm).
* History of CTCAE grade 3 or higher cardiovascular disease or condition known to exist prior to the patient's initial diagnosis of cHL.

  * Note: exceptions are made for congenital conditions considered fully resolved by surgery and chronic conditions such as hypertension or hypercholesterolemia that are managed with medical intervention.
* History of an immunodeficiency that existed prior to cHL diagnosis, such as primary immunodeficiency syndromes, organ transplant recipients and conditions requiring systemic immunosuppressive agents.