Prospective medical assessment of adults surviving childhood cancer: study design, cohort characteristics, and feasibility of the St. Jude Lifetime Cohort study

Abstract

Background: To facilitate prospective medical assessment of adults surviving pediatric malignancies and advance knowledge about long-term childhood cancer survivor health, St. Jude Children's Research Hospital (SJCRH) is establishing a lifetime cohort of survivors.

Methods: Eligibility criteria for inclusion in the St. Jude Lifetime Cohort (SJLIFE) study include: (1) diagnosis of childhood malignancy treated at SJCRH; (2) survival ≥ 10 years from diagnosis; and (3) current age ≥ 18 years. Three levels of participation are offered: (1) comprehensive evaluation on SJCRH campus; (2) limited home evaluation; or (3) completion of health surveys only. A systematic recruitment structure based upon blocks of 50 patients initially focused on leukemia and lymphoma survivors and patients eligible for pilot studies.

Results: As of January 1, 2010, 1,625 (42%) of 3,900 eligible ≥ 10-year survivors have been contacted. Among the first 1,000 potentially eligible survivors selected for recruitment, 971 were subsequently confirmed to fulfill eligibility criteria. To date, 898/971 (92.5%) have been successfully contacted of whom 825 (91.8%) have agreed to participate. Among participants, 88.6% agreed to comprehensive medical evaluation, 0.4% limited local evaluation, and 11.0% survey only. Anticipated minimum overall participation rate for medical evaluation is 75.3% (731/971). Comparison of those contacted who agreed versus declined to participate revealed a greater proportion of males who declined participation (P = 0.001).

Conclusions: Early results of the SJLIFE study support its feasibility to recruit aging childhood cancer survivors to research investigations evaluating late health outcomes by medical assessments.

Figure 1

To facilitate early comparison of survivors agreeing or declining to study participation and more rapid reporting of outcomes, the SJLIFE study utilizes a staged recruitment strategy to fully characterize groups of 50 survivors in targeted diagnostic or treatment categories. The figure illustrates recruitment outcomes as of January 1, 2010 among all survivors (A) and among survivors in the first 20 recruitment blocks (B) identified as potentially eligible for SJLIFE study participation. “One-year hold” in the “Not Contacted” block refers to participants the study team has not been able to directly contact, but for whom addresses and/or telephone numbers have not been determined to be inaccurate.

Figure 2

Geographic distribution by last known residence of 3900 eligible survivors from the continental United States meeting eligibility criteria for SJLIFE participation as of January 1, 2010. Does not include 3 survivors residing in Alaska and 2 residing in Hawaii.