Background: Treatments for childhood cancer have evolved in recent decades, with the goal of maximizing cure rates while minimizing the adverse effects of therapy. We aimed to evaluate incidence patterns of serious chronic health conditions in long-term survivors of childhood cancer across three decades of diagnosis and treatment. Methods: We used data from the Childhood Cancer Survivor Study, a retrospective cohort with prospective follow-up of 5-year survivors of childhood cancer diagnosed from 1970-1999 in North America. We examined the cumulative incidence of severe to fatal chronic health conditions occurring up to 20 years post-diagnosis among survivors, compared by diagnosis decade. Multivariable regression models estimated hazard ratios per diagnosis decade, and addition of treatment variables assessed whether treatment changes attenuated associations between diagnosis decade and chronic disease risk. Findings: Among 23,601 survivors (median age 28, range 5-63 years; 46% female), the 20-year cumulative incidence of at least one grade 3-5 chronic condition decreased significantly from 33·2% (95% CI, 32·0%-34·3%) in those diagnosed 1970-1979 to 29·3% (95% CI, 28·4%-30·2%, p<0·0001) in 1980-1989, and 27·5% (95% CI, 26·4%-28·6%, p=0·012 vs. 1980-1989) in 1990-1999. By comparison, the 20-year cumulative incidence of at least one grade 3-5 condition among 5,051 siblings was 4·6% (95% CI,3·9%-5·2%). The 15-year cumulative incidence of at least one grade 3-5 condition was lower for survivors diagnosed 1990-1999 compared to 1970-1979 for Hodgkin lymphoma (17·7% vs. 26·4%, p<0·0001), non-Hodgkin lymphoma (16·9% vs. 23·8%, p=0.0053), astrocytoma (30·5% vs. 47·3%, p<0·0001), Wilms tumor (11·9% vs. 17·6%, p=0·034), soft tissue sarcoma (28·3% vs. 36·5%, p=0·021), and osteosarcoma (65·6% vs. 87·5%, p<0·0001). In contrast, the 15-year cumulative incidence of at least one grade 3-5 condition was higher (1990-1999 vs. 1970-1979) for medulloblastoma/PNET (58·9% vs. 42·9%, p=0·00060) and neuroblastoma (25·0% vs. 18·0%, p=0·0045). Results were consistent with changes in treatment as a mediator of the association between diagnosis decade and risk of grade 3-5 chronic conditions for astrocytoma, Hodgkin lymphoma, and non-Hodgkin lymphoma. Temporal decreases were observed for endocrinopathies, subsequent malignant neoplasms, musculoskeletal conditions, and gastrointestinal conditions, while hearing loss increased. Interpretation: Our results provide novel evidence that more recently treated survivors of childhood cancer have experienced improvements in health outcomes, consistent with efforts over the same time period to modify childhood cancer treatment regimens to maximize cure while reducing risk of late effects. Continuing advances in cancer therapy offer promise of further reducing the risk of late effects. However, achieving a cure for childhood cancer continues to come at a cost for many survivors, emphasizing the importance of long-term follow-up care for this population. Funding: National Cancer Institute and t...

Purpose Little is known about the breast cancer risk among childhood cancer survivors who did not receive chest radiotherapy. We sought to determine the magnitude of risk and associated risk factors for breast cancer among these women. Patients and Methods We evaluated cumulative breast cancer risk in 3,768 female childhood cancer survivors without a history of chest radiotherapy who were participants in the Childhood Cancer Survivor Study. Results With median follow up of 25.5 years (range, 8 to 39 years), 47 women developed breast cancer at a median age of 38.0 years (range, 22 to 47 years) and median of 24.0 years (range, 10 to 34 years) from primary cancer to breast cancer. A four-fold increased breast cancer risk (standardized incidence ratio [SIR] = 4.0; 95% CI, 3.0 to 5.3) was observed when compared with the general population. Risk was highest among sarcoma and leukemia survivors (SIR = 5.3; 95% CI, 3.6 to 7.8 and SIR = 4.1; 95% CI, 2.4 to 6.9, respectively). By the age of 45 years, the cumulative incidence of breast cancer in sarcoma and leukemia survivors was 5.8% (95% CI, 3.7 to 8.4) and 6.3% (95% CI, 3.0 to 11.3), respectively. No other primary cancer diagnosis was associated with an elevated risk. Alkylators and anthracyclines were associated with an increased breast cancer risk in a dose-dependent manner (P values from test for trend were both < .01). Conclusions Women not exposed to chest radiotherapy who survive childhood sarcoma or leukemia have an increased risk of breast cancer at a young age. The data suggest high-dose alkylator and anthracycline chemotherapy increase the risk of breast cancer. This may suggest a possible underlying gene-environment interaction that warrants further study.

With improvements in cancer treatment and supportive care, a growing population of survivors of childhood cancer at risk for significant and potentially life-threatening late effects has been identified. To provide a current snapshot of the models of care from countries with varying levels of resources and health care systems, stakeholders in childhood cancer survivorship clinical care and research were identified from 18 countries across five continents. Stakeholders responded to a survey and provided a brief narrative regarding the current state of survivorship care. Findings indicate that among pediatric-age survivors of childhood cancer (allowing for differences in age cutoffs across countries), resources are generally available, and a large proportion of survivors are seen by a physician familiar with late effects in most countries. After survivors transition to adulthood, only a minority are seen by a physician familiar with late effects. Despite the need to improve communication between pediatric oncology and primary care, only a few countries have existing national efforts to educate primary care physicians, although many more reported that educational programs are in development. These data highlight common challenges and potential solutions for the lifelong care of survivors of childhood cancer. Combining risk-based and patient-oriented solutions for this population is likely to benefit both providers and patients.