Curative therapy for pediatric malignancies has produced a growing population of adults formerly treated for childhood cancer who are at risk for health problems^1-3 that appear to increase with aging.^2-5 The prevalence of cancer-related toxic effects that are systematically ascertained through formal clinical assessments has not been well studied. Ongoing clinical evaluation of well-characterized cohorts is important to advance knowledge about the influence of aging on cancer-related morbidity and mortality and to guide the development of health screening recommendations and health-preserving interventions.

The development of curative therapy for most pediatric malignancies provides the opportunity to investigate the impact of cancer treatment on health status of large numbers of long-term survivors. Numerous studies have established that cancer and its treatment predispose to late morbidity and increase the risk of early mortality in long-term childhood cancer survivors.^1-8 In general, children with aggressive tumor histologies have required more intensive treatment, which predispose them to heightened risks of physical morbidity. Treatment-related late sequelae with significant potential impact on physical functioning include neurocognitive dysfunction, cardiopulmonary toxicity, endocrinopathy, and second malignancy. The frequency and severity of many of the common sequelae have been correlated with sex, age at diagnosis, and cumulative dose-exposures of specific treatment modalities.^9-12

Characterization of toxicity associated with cancer and its treatment is essential to quantify risk, inform optimization of therapeutic approaches for newly diagnosed patients, and guide health surveillance recommendations for long-term survivors. The NCI Common Terminology Criteria for Adverse Events (CTCAE) provides a common rubric for grading severity of adverse outcomes in cancer patients that is widely used in clinical trials. The CTCAE has also been used to assess late cancer treatment-related morbidity but is not fully representative of the spectrum of events experienced by pediatric and aging adult survivors of childhood cancer. Also, CTCAE characterization does not routinely integrate detailed patient-reported and medical outcomes data available from clinically assessed cohorts. To address these deficiencies, we standardized the severity grading of long-term and late-onset health events applicable to childhood cancer survivors across their lifespan by modifying the existing CTCAE v4.03 criteria and aligning grading rubrics from other sources for chronic conditions not included or optimally addressed in the CTCAE v4.03. This article describes the methods of late toxicity assessment used in the St. Jude Lifetime Cohort Study, a clinically assessed cohort in which data from multiple diagnostic modalities and patient-reported outcomes are ascertained. Cancer Epidemiol Biomarkers Prev; 26(5); 666–74. ©2016 AACR.

Progress in therapy has made survival into adulthood a reality for most children, adolescents, and young adults with a cancer diagnosis today. Notably, this growing population remains vulnerable to a variety of long-term therapy-related sequelae. Systematic ongoing follow-up of these patients is, therefore, important to provide for early detection of and intervention for potentially serious late-onset complications. In addition, health counseling and promotion of healthy lifestyles are important aspects of long-term follow-up care to promote risk reduction for physical and emotional health problems that commonly present during adulthood. Both general and subspecialty health care providers are playing an increasingly important role in the ongoing care of childhood cancer survivors, beyond the routine preventive care, health supervision, and anticipatory guidance provided to all patients. This report is based on the guidelines that have been developed by the Children’s Oncology Group to facilitate comprehensive long-term follow-up of childhood, adolescent, and young adult cancer survivors (www.survivorshipguidelines.org).