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 MRIwithout sedation).

• History of pathologically confirmed classical Hodgkin Lymphoma (cHL) initiallydiagnosed when the patient was >= 2 and < 22 years of age.

• As part of frontline therapy for cHL, the patient must have received a cumulativedoxorubicin equivalent anthracycline dose of ≥ 200 mg/m^2 as estimated indoxorubicin isotoxic equivalents dose conversion calculation.

• Note: History of COG therapeutic trial participation is not required.Institutional records (e.g., clinic note, treatment summary, chemotherapyroadmap) can be used as reference documentation of receipt of anthracyclinedose.

• All systemic cancer treatment must have been completed ≥ 2 years prior to studyenrollment.

• Not known to have had a primary event (relapse/second malignancy/death).

• Note: Subjects treated at another institution are eligible if they are nowbeing followed at the current COG institution, if the study procedures can beperformed 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 beable 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., fordisease progression or recurrence, or subsequent malignant neoplasm).

• History of CTCAE grade 3 or higher cardiovascular disease or condition known toexist prior to the patient's initial diagnosis of cHL.

• Note: exceptions are made for congenital conditions considered fully resolvedby surgery and chronic conditions such as hypertension or hypercholesterolemiathat are managed with medical intervention.

• History of an immunodeficiency that existed prior to cHL diagnosis, such as primaryimmunodeficiency syndromes, organ transplant recipients and conditions requiringsystemic immunosuppressive agents.