Lillian R. Meacham

Chronic Disease in the Childhood Cancer Survivor Study Cohort: A Review of Published Findings

A primary objective of the Childhood Cancer Survivor Study (CCSS) is to characterize the major chronic health conditions faced by childhood cancer survivors, and to determine the risk factors for those conditions. In order to characterize these conditions, at entry into the study, participants completed questionnaires that documented self-reported chronic illnesses, symptoms, and medications. Over time, follow-up questionnaires (administered approximately every 2 to 3 years) have allowed analysis of changes in symptoms and disease burden. To date, analyses have been completed which describe the profile of chronic disease in the cohort at first entry into the study and for specific subgroups, defined by primary cancer, by specific exposures, and by demographic factors.1,2 Generally, these analyses estimate risk of chronic disease by calculating a risk estimate for self-reported symptoms or conditions. Relative risks for chronic disease or specific conditions are calculated comparing the survivor cohort with the sibling cohort or population norms. In addition, relative risk for an outcome in a subgroup with a specific treatment exposure or demographic characteristic is calculated relative to a comparison group without that specific factor of interest. Cumulative incidence of specific chronic illnesses is estimated in many of the reports, and analyses of chronic illnesses in each of the survivor groups by primary diagnosis are completed (acute lymphoblastic leukemia [ALL],3 acute myeloid leukemia [AML],4 and rhadbdomyosarcoma5) or in progress (neuroblastoma, bone sarcoma, renal tumors, lymphomas, and brain tumors). This review presents the completed analyses of overall chronic illness in the original cohort and then describes findings by organ system. Specific chronic diseases reported here will include: endocrinologic disorders (including thyroid disease, disorders of growth, weight, and pubertal regulation), osteonecrosis, cardiac disease, pulmonary conditions, and neurosensory/neurologic adverse outcomes. Adverse outcomes in some domains which might be considered chronic illnesses—secondary cancers, emotional and psychological disorders, pain—are not covered herein, but are reviewed separately in other articles within this issue of Journal of Clinical Oncology. For some outcomes, only subsets of the cohort have been analyzed, often because a hypothesis regarding a specific exposure or disease (eg, weight regulation in leukemia survivors or stroke after neck radiation therapy [RT]) has been explored. Analyses in progress, and not included in this report, include risk of renal and urinary disorders, gastrointestinal diseases, and more in depth cohort-wide characterizations of cardiovascular disease. Additional studies to characterize further longitudinal changes in risk as the cohort ages are planned.

Modifiable risk factors and major cardiac events among adult survivors of childhood cancer.

PURPOSE To evaluate the relative contribution of modifiable cardiovascular risk factors on the development of major cardiac events in aging adult survivors of childhood cancer. PATIENTS AND METHODS Among 10,724 5-year survivors (median age, 33.7 years) and 3,159 siblings in the Childhood Cancer Survivor Study, the prevalence of hypertension, diabetes mellitus, dyslipidemia, and obesity was determined, along with the incidence and severity of major cardiac events such as coronary artery disease, heart failure, valvular disease, and arrhythmia. On longitudinal follow-up, rate ratios (RRs) of subsequent cardiac events associated with cardiovascular risk factors and cardiotoxic therapy were assessed in multivariable Poisson regression models. RESULTS Among survivors, the cumulative incidence of coronary artery disease, heart failure, valvular disease, and arrhythmia by 45 years of age was 5.3%, 4.8%, 1.5%, and 1.3%, respectively. Two or more cardiovascular risk factors were reported by 10.3% of survivors and 7.9% of siblings. The risk for each cardiac event increased with increasing number of cardiovascular risk factors (all P(trend) < .001). Hypertension significantly increased risk for coronary artery disease (RR, 6.1), heart failure (RR, 19.4), valvular disease (RR, 13.6), and arrhythmia (RR, 6.0; all P values < .01). The combined effect of chest-directed radiotherapy plus hypertension resulted in potentiation of risk for each of the major cardiac events beyond that anticipated on the basis of an additive expectation. Hypertension was independently associated with risk of cardiac death (RR, 5.6; 95% CI, 3.2 to 9.7). CONCLUSION Modifiable cardiovascular risk factors, particularly hypertension, potentiate therapy-associated risk for major cardiac events in this population and should be the focus of future interventional studies.

Diabetes mellitus in long-term survivors of childhood cancer - Increased risk associated with radiation therapy: A report for the childhood cancer survivor study

BACKGROUND Childhood cancer survivors are at increased risk of morbidity and mortality. To further characterize this risk, this study aimed to compare the prevalence of diabetes mellitus (DM) in childhood cancer survivors and their siblings. METHODS Participants included 8599 survivors in the Childhood Cancer Survivor Study (CCSS), a retrospectively ascertained North American cohort of long-term survivors who were diagnosed between 1970 and 1986 as well as 2936 randomly selected siblings of the survivors. The main outcome was self-reported DM. RESULTS The mean ages of the survivors and the siblings were 31.5 years (age range, 17.0-54.1 years) and 33.4 years (age range, 9.6-58.4 years), respectively. Diabetes mellitus was reported in 2.5% of the survivors and 1.7% of the siblings. After adjustment for body mass index, age, sex, race/ethnicity, household income, and insurance, the survivors were 1.8 times more likely than the siblings to report DM (95% confidence interval [CI], 1.3-2.5; P < .001), with survivors who received total body irradiation (odds ratio [OR], 12.6; 95% CI, 6.2-25.3; P < .001), abdominal irradiation (OR, 3.4; 95% CI, 2.3-5.0; P < .001), and cranial irradiation (OR, 1.6; 95% CI 1.0-2.3; P = .03) at increased risk. In adjusted models, an increased risk of DM was associated with total body irradiation (OR, 7.2; 95% CI, 3.4-15.0; P < .001), abdominal irradiation (OR, 2.7; 95% CI, 1.9-3.8; P < .001), use of alkylating agents (OR, 1.7; 95% CI, 1.2-2.3; P < .01), and younger age at diagnosis (0-4 years; OR, 2.4; 95% CI, 1.3-4.6; P < .01). CONCLUSION Childhood cancer survivors treated with total body or abdominal irradiation have an increased risk of diabetes that appears unrelated to body mass index or physical inactivity.

Cardiovascular Risk Factors in Adult Survivors of Pediatric Cancer—A Report from the Childhood Cancer Survivor Study

Background: Childhood cancer survivors are at higher risk of morbidity and mortality from cardiovascular disease compared with the general population. Methods: Eight thousand five hundred ninety-nine survivors (52% male) and 2,936 siblings (46% male) from the Childhood Cancer Survivor Study, a retrospectively ascertained, prospectively followed study of persons who survived 5 years after childhood cancer diagnosed from 1970 to 1986, were evaluated for body mass index of ≥30 kg/m2 based on self-reported heights and weights and self-reported use of medications for hypertension, dyslipidemia, and impaired glucose metabolism. The presence of three or more of the above constituted Cardiovascular Risk Factor Cluster (CVRFC), a surrogate for Metabolic Syndrome. Results: Survivors were more likely than siblings to take medications for hypertension [odds ratio (OR), 1.9; 95% confidence interval (95% CI), 1.6-2.2], dyslipidemia (OR, 1.6; 95% CI, 1.3-2.0) or diabetes (OR, 1.7; 95% CI, 1.2-2.3). Among these young adults (mean age of 32 years for survivors and 33 years for siblings), survivors were not more likely than siblings to be obese or have CVRFC. In a multivariable logistic regression analysis, factors associated with having CVRFC included older age at interview [≥40 versus <30 years of age (OR, 8.2; 95% CI, 3.5-19.9)], exposure to total body irradiation (OR, 5.5; 95% CI, 1.5-15.8) or radiation to the chest and abdomen (OR, 2.3; 95% CI, 1.2-2.4), and physical inactivity (OR, 1.7; 95% CI, 1.1-2.6). Conclusions: Among adult survivors of pediatric cancer, older attained age, exposure to total body irradiation or abdominal plus chest radiation, and a sedentary life-style are associated with CVRFC. Cancer Epidemiol Biomarkers Prev; 19(1); 170–81

Bone Mineral Density Deficits in Survivors of Childhood Cancer: Long-term Follow-up Guidelines and Review of the Literature

The development of curative therapy for most pediatric malignancies has produced a growing population of childhood cancer survivors who are at increased risk for a variety of health problems resulting from their cancer or its treatment. Because of the fact that many treatment-related sequelae may not become clinically apparent until the survivor attains maturity or begins to age, the ability of primary care providers to anticipate late effects of treatment is essential for providing timely interventions that prevent or correct these sequelae and their adverse effects on quality of life. Altered bone metabolism during treatment for childhood cancer may interfere with attainment of peak bone mass, potentially predisposing to premature onset of and more severe complications related to osteopenia and osteoporosis. Bone mineral deficits have been reported after treatment for a variety of pediatric malignancies and represent morbidity that can be reduced or prevented through lifestyle changes and attention to other common cancer-related sequelae such as hypogonadism. The Childrens Oncology Group long-term follow-up guidelines for survivors of childhood, adolescent, and young adult cancers provide risk-based surveillance recommendations that are based on expert opinion and review of the scientific literature for potential late effects of pediatric cancer therapy including osteopenia. This review summarizes the existing literature that has defined characteristics of cancer survivors at risk for bone mineral deficits and contributed to the surveillance and counseling recommendations outlined in the Childrens Oncology group long-term follow-up guidelines.

Female Reproductive Health After Childhood, Adolescent, and Young Adult Cancers: Guidelines for the Assessment and Management of Female Reproductive Complications

PURPOSE As more young female patients with cancer survive their primary disease, concerns about reproductive health related to primary therapy gain relevance. Cancer therapy can often affect reproductive organs, leading to impaired pubertal development, hormonal regulation, fertility, and sexual function, affecting quality of life. METHODS The Childrens Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancer (COG-LTFU Guidelines) are evidence-based recommendations for screening and management of late effects of therapeutic exposures. The guidelines are updated every 2 years by a multidisciplinary panel based on current literature review and expert consensus. RESULTS This review summarizes the current task force recommendations for the assessment and management of female reproductive complications after treatment for childhood, adolescent, and young adult cancers. Experimental pretreatment as well as post-treatment fertility preservation strategies, including barriers and ethical considerations, which are not included in the COG-LTFU Guidelines, are also discussed. CONCLUSION Ongoing research will continue to inform COG-LTFU Guideline recommendations for follow-up care of female survivors of childhood cancer to improve their health and quality of life.

Twenty years of follow-up among survivors of childhood and young adult acute myeloid leukemia: A report from the Childhood Cancer Survivor Study

Limited data exist on the comprehensive assessment of late medical and social effects experienced by survivors of childhood and young adult acute myeloid leukemia (AML).

Obesity in pediatric oncology.

Todays obesity pandemic began in the United States, spread to Western Europe and other developed regions, and is emerging in developing countries. Its influences on outcomes of childhood cancer are unknown. A recent Childrens Oncology Group symposium considered epidemiology of obesity, pharmacology of chemotherapy and outcomes in obese adults with cancer, excess mortality in obese pediatric patients with acute myeloid leukemia (AML), and complications in obese survivors. The salient points are summarized herein. Body mass index (BMI) is the accepted index of weight for height and age. In the US, obesity prevalence (BMI > 95th centile) is increasing in all pediatric age groups and accelerating fastest among black and Hispanic adolescents. Pharmacologic investigations are few and limited: half‐life, volume of distribution, and clearance in obese patients vary between drugs. Obese adults with solid tumors generally experience less toxicity, suggesting underdosing. For patients undergoing bone marrow transplantation, obese adults generally experience greater toxicity. In pediatric acute myeloblastic leukemia, obese patients have greater treatment‐related mortality (TRM), similar toxicity and relapse rates, and inferior survival compared with patients who are not obese. An excess of female survivors of childhood leukemia who received cranial irradiation are obese. Ongoing treatment effects of childhood cancer may predispose to a sedentary lifestyle. These findings call for measures to prevent obesity, retrospective and prospective studies of chemotherapy pharmacology of analyzed according to BMI and outcomes, additional studies of the obesity impact on outcomes in pediatric cancer, and promotion of a healthy lifestyle among survivors.

Endocrine late effects of childhood cancer therapy: a report from the Children's Oncology Group.

Pediatric oncologists are curing increasing numbers of patients with childhood cancer, and most children diagnosed with a malignancy may now be expected to become long-term survivors. As the number of childhood cancer survivors grows, so too does the need for evidence-based surveillance of the long-term effects of cancer therapy. Long-term effects involving the endocrine system represent a frequent complication of therapy. The Children’s Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancers(COG LTFUG), most recently updated in 2006, provide a summary of the known endocrine late effects of surgery, radiation, chemotherapy, and stem cell transplant. This paper summarizes the scope and nature of the endocrine late effects of childhood cancer therapy based upon a review of the pertinent medical literature, and demonstrates how pediatric oncologists can use these guidelines in clinical practice.

A multidisciplinary review of nutrition considerations in the pediatric oncology population: a perspective from children's oncology group.

Over the past few decades, great progress has been made in the survival rates of childhood cancer. As survival rates have improved, there has been an increased focus on supportive care. Nutrition is a supportive-care modality that has been associated with improved tolerance to chemotherapy, improved survival, increased quality of life, and decreased risk of infection in children undergoing anticancer therapy. Guidelines and assessment criteria have been proposed for the nutrition management of a child with cancer; however, there is no consistent use of criteria among institutions treating children with cancer. This review will present the current evidence and standards of practice incorporating aspects of nutrition, nursing, pharmacology, and psychosocial challenges to consider in the nutrition management of a child with cancer. Recommendations for clinical practice are presented.