Childhood cancer survivors are at increased risk for premature atherosclerotic cardiovascular disease (ASCVD) due to cancer treatment-related exposures, including radiation therapy and platinum-based chemotherapy. Current ASCVD risk assessment tools may underestimate cardiovascular risk in younger survivors. This observational study performs detailed cardiovascular phenotyping using imaging, blood-based biomarkers, and vascular function testing among adult survivors enrolled in the St. Jude Lifetime Cohort (SJLIFE), with comparison to community controls, to better characterize subclinical ASCVD risk and inform survivor-specific prevention strategies.

Primary Objective:

Perform deeper phenotyping of SJLIFE participants at treatment-related risk of atherosclerotic cardiovascular disease [ASCVD] to facilitate early detection of pathophysiological targets appropriate for remediation.

Secondary Objectives:

Determine the distribution of lipoprotein (a) levels and prevalence of elevated levels among survivors with any treatment related exposure-based risk for ASCVD overall and then compared to community controls.

Evaluate prevalence of clinical and imaging markers of ASCVD risk among survivors exposed only to platinum chemotherapy and compare that to community controls.

Survivors of childhood cancer experience substantially increased risk of ischemic heart disease and stroke compared to the general population. This excess risk is largely driven by cancer therapy exposures such as chest or neck radiation and platinum-based chemotherapy. However, most evidence-based ASCVD screening and prevention guidelines are derived from populations aged 40 years or older without cancer therapy exposure, leaving younger survivors inadequately risk stratified.

This study leverages the St. Jude Lifetime Cohort (SJLIFE) to conduct enhanced cardiovascular phenotyping among survivors at treatment-related risk for ASCVD. Participants undergo coronary artery calcium (CAC) scoring using low-dose non-contrast ECG-gated CT, bilateral carotid ultrasound to assess carotid stenosis and intima-media thickness, blood-based measurement of lipoprotein(a), and noninvasive vascular function testing including pulse wave velocity, augmentation index, and arterial elasticity. A cohort of community control participants enrolled in SJLIFE undergoes identical testing.

The primary objectives are to determine the prevalence of abnormal CAC and carotid stenosis among at-risk survivors and to compare findings with community controls. Secondary objectives include characterization of lipoprotein(a) levels and assessment of ASCVD markers among survivors exposed solely to platinum chemotherapy.

The study uses a cross-sectional design with prospective longitudinal follow-up through ongoing participation in SJLIFE. Results are intended to inform future survivor-specific screening approaches and interventional trials.

Inclusion Criteria:

- SJLIFE Survivor or Control

• Age ≥18 years
• Enrolled in the St. Jude Lifetime Cohort (SJLIFE)
• Participant or legal guardian/representative is able and willing to give informed consent.

SJLIFE Survivor only

• Participant has been treated with at least one of the following cancer therapies:

platinum chemotherapy, neck radiation exposure of at least 1000 centigray (cGy), or chest radiation exposure of at least 1000 cGy (with potential exposure to the heart).

Exclusion Criteria:

SJLIFE Survivor or Control

• Previous stroke or intervention for severe carotid arterial disease including carotid endarterectomy or carotid angioplasty and stent placement.
• Previous myocardial infarction or intervention for severe cardiovascular disease including Coronary Artery Bypass Graft (CABG), coronary stent placement or coronary angioplasty.
• History of aortic valve replacement
• Inability or unwillingness of research participant or legal guardian/representative to give written informed consent.

Control Only

• First degree relative of SJLIFE Survivor
• History of cancer

Participants are identified through existing enrollment in the St. Jude Lifetime Cohort (SJLIFE). Childhood cancer survivors are selected based on prior cancer treatment exposures associated with increased risk of atherosclerotic cardiovascular disease and are invited to participate during scheduled SJLIFE evaluations. Community control participants are selected from the SJLIFE comparison group and are frequency matched to survivors by age and sex. Participation is voluntary, and no randomization is used.

Individual participant de-identified datasets containing the variables analyzed in the published article will be made available (related to the study primary or secondary objectives contained in the publication). Supporting documents such as the protocol, statistical analyses plan, and informed consent are available through the ClinicalTrials.gov website for the specific study. Data used to generate the published article will be made available at the time of article publication. Investigators who seek access to individual level de-identified data will contact the computing team in the Department of Biostatistics (ClinTrialDataRequest@stjude.org) who will respond to the data request.

Data will be made available at the time of article publication.

Data will be provided to researchers following a formal request with the following information: full name of requestor, affiliation, data set requested, and timing of when data is needed. As an informational point, the lead statistician and study principal investigator will be informed that primary results datasets have been requested.