Pooled Analysis of Meningioma Risk Following Treatment for Childhood Cancer.

Importance: Meningioma is the most common subsequent neoplasm following cranial irradiation among survivors of childhood cancer, but there are still uncertainties regarding the magnitude of the radiation dose-response association, potential modifiers of radiation risks, and the role of chemotherapy. Objective: To evaluate meningioma risk in survivors of childhood cancer following radiotherapy and chemotherapy and identify possible modifying factors of radiation-associated risk. Design, Setting, and Participants: This international case-control study pooled data from 4 nested case-control studies of survivors of childhood cancer diagnosed between 1942 and 2000, followed through 2016. Cases were defined as participants diagnosed with a subsequent meningioma. Controls were matched to cases based on sex, age at first cancer diagnosis, and duration of follow-up. Data were analyzed from July 2019 to June 2022. Exposures: Radiation dose (Gy) to the meningioma site and cumulative chemotherapy doses, including intrathecal and systemic methotrexate doses. Main Outcomes and Measures: The main outcome was subsequent meningioma, assessed using odds ratios (ORs) and excess odds ratios per gray (EOR/Gy). Results: The analysis included 273 survivors of childhood cancer who developed meningioma (cases) and 738 survivors who did not (controls), with a total of 1011 individuals (median [IQR] age at first cancer diagnosis 5.0 [3.0-9.2] years; 599 [59.2%] female). Median (IQR) time since first cancer was 21.5 (15.0-27.0) years. Increasing radiation dose was associated with increased risk of meningioma (EOR/Gy, 1.44; 95% CI, 0.62-3.61), and there was no evidence of departure from linearity (P = .90). Compared with survivors who were not exposed to radiation therapy, those who received doses of 24 Gy or more had more than 30-fold higher odds of meningioma (OR, 33.66; 95% CI, 14.10-80.31). The radiation dose-response association was significantly lower among patients treated at age 10 years or older compared with those treated before age 10 years (EOR/Gy, 0.57; 95% CI, 0.18-1.91 vs 2.20; 95% CI, 0.87-6.31; P for heterogeneity = .03). Risk associated with radiation remained significantly elevated 30 years after exposure (EOR/Gy, 3.76; 95% CI, 0.77-29.15). We found an increased risk of meningioma among children who had received methotrexate (OR, 3.43; 95% CI, 1.56-7.57), but no evidence of a dose-response association or interaction with radiation dose. Conclusions and Relevance: These findings suggest that the meninges are highly radiosensitive, especially for children treated before age 10 years. These results support the reduction in whole-brain irradiation over recent decades and the prioritization of approaches that limit radiation exposure in healthy tissue for children. The persistence of elevated risks of meningiomas for 30 years after cranial radiotherapy could help inform surveillance guidelines.

Temporal changes in the probability of live birth among female survivors of childhood cancer: A population-based Adult Life After Childhood Cancer in Scandinavia (ALiCCS) study in five nordic countries.

BACKGROUND: During the past 4 decades, there has been a growing focus on preserving the fertility of patients with childhood cancer; however, no large studies have been conducted of live births across treatment decades during this period. Therefore, the authors estimated the potential birth deficit in female childhood cancer survivors and the probability of live births. METHODS: In total, 8886 women were identified in the 5 Nordic cancer registries in whom a childhood cancer had been diagnosed during 1954 through 2006. A population comparison cohort of 62,903 women was randomly selected from the central population registries matched by age and country. All women were followed for live births recorded in medical birth registries. The cumulative probability and the risk ratio (RR) with 95% confidence intervals (CIs) of a live birth were calculated by maternal age across treatment decades. RESULTS: The probability of a live birth increased with treatment decade, and, at age 30 years, the rate for survivors most recently diagnosed was close to the rate among the general population (1954-1969: RR, 0.65 [95% CI, 0.54-0.78]; 1970s: RR, 0.67 [95% CI, 0.60-0.74]; 1980s: RR, 0.69 [95% CI, 0.64-0.74]; 1990s: RR, 0.91 [95% CI, 0.87-0.95]; 2000s: RR, 0.94 [95% CI, 0.91-0.97]). CONCLUSIONS: Female childhood cancer survivors had a lower probability of a live birth than women in the general population, although, in survivors diagnosed after 1989, the probability was close to that of the general population. Because the pattern of live births differs by cancer type, continuous efforts must be made to preserve fertility, counsel survivors, and refer them rapidly to fertility treatment if necessary. LAY SUMMARY: The purpose of this study was to compare the probability of giving birth to a liveborn child in female survivors of childhood cancer with that of women in the general population. Survivors of childhood cancer had a lower probability of live births than women in the general population, although survivors diagnosed after 1989 had a probability close to that of the general population. Continuing focus on how to preserve the potential for fertility among female patients with childhood cancer during treatment is important to increase their chances of having a child.

Dose-volume effects of breast cancer radiation therapy on the risk of second oesophageal cancer.

PURPOSE: To investigate the relationship between oesophagus dose-volume distribution and long-term risk of oesophageal cancer after radiation therapy for breast cancer. MATERIALS AND METHODS: In a case-control study nested within a cohort of 289,748 ≥5-year survivors of female breast cancer treated in 1943-2003 in five countries, doses to the second primary cancer (DSPC) and individual dose-volume histograms (DVH) to the entire oesophagus were reconstructed for 252 oesophageal cancer cases and 488 matched controls (median follow-up time: 13, range: 5-37 years). Using conditional logistic regression, we estimated excess odds ratios (EOR) of oesophageal cancer associated with DVH metrics. We also investigated whether DVH metrics confounded or modified DSPC-related -risk estimates. RESULTS: Among the DVH metrics evaluated, median dose (Dmedian) to the entire oesophagus had the best statistical performance for estimating risk of all histological types combined (EOR/Gy = 0.071, 95% confidence interval [CI]: 0.018 to 0.206). For squamous cell carcinoma, the most common subtype, the EOR/Gy for Dmedian increased by 31% (95% CI: 3% to 205%) for each increment of 10% of V30 (p = 0.02). Adjusting for DVH metrics did not materially change the EOR/Gy for DSPC, but there was a borderline significant positive interaction between DSPC and V30 (p = 0.07). CONCLUSION: This first study investigating the relationship between oesophagus dose-volume distribution and oesophageal cancer risk showed an increased risk per Gy for Dmedian with larger volumes irradiated at high doses. While current techniques allows better oesophagus sparing, constraints applied to Dmedian and V30 could potentially further reduce the risk of oesophageal cancer.

Late mortality and chronic health conditions in long-term survivors of early-adolescent and young adult cancers: a retrospective cohort analysis from the Childhood Cancer Survivor Study.

BACKGROUND: Treatment outcomes among survivors of cancer diagnosed during adolescence and early young adulthood have not been characterised independently of survivors of cancers diagnosed during childhood. We aimed to describe chronic health conditions and all-cause and cause-specific mortality among survivors of early-adolescent and young adult cancer. METHODS: The Childhood Cancer Survivor Study (CCSS) is a retrospective cohort study with longitudinal follow-up of 5-year survivors diagnosed with cancer before the age of 21 years at 27 academic institutions in the USA and Canada between 1970 and 1999. We evaluated outcomes among survivors of early-adolescent and young adult cancer (aged 15-20 years at diagnosis) and survivors diagnosed at age younger than 15 years (matched on primary cancer diagnosis, including leukaemia, lymphoma, CNS tumours, neuroblastoma, Wilms tumour, soft-tissue sarcomas, and bone cancer) by comparing both groups to siblings of the same age. Mortality was ascertained with the National Death Index. Chronic health conditions were classified with the Common Terminology Criteria for Adverse Events. Standardised mortality ratios (SMRs) were estimated with age-specific, sex-specific, and calendar year-specific US rates. Cox proportional hazard models estimated hazard ratios (HRs) for chronic health conditions and 95% CIs. FINDINGS: Among 5804 early-adolescent and young adult survivors (median age 42 years, IQR 34-50) the SMR compared to the general population for all-cause mortality was 5·9 (95% CI 5·5-6·2) and among 5804 childhood cancer survivors (median age 34 years; 27-42), it was 6·2 (5·8-6·6). Early-adolescent and young adult survivors had lower SMRs for death from health-related causes (ie, conditions that exclude recurrence or progression of the primary cancer and external causes, but include the late effects of cancer therapy) than did childhood cancer survivors (SMR 4·8 [95% CI 4·4-5·1] vs 6·8 [6·2-7·4]), which was primarily evident more than 20 years after cancer diagnosis. Early-adolescent and young adult cancer survivors and childhood cancer survivors were both at greater risk of developing severe and disabling, life-threatening, or fatal (grade 3-5) health conditions than siblings of the same age (HR 4·2 [95% CI 3·7-4·8] for early adolescent and young adult cancer survivors and 5·6 [4·9-6·3] for childhood cancer survivors), and at increased risk of developing grade 3-5 cardiac (4·3 [3·5-5·4] and 5·6 [4·5-7·1]), endocrine (3·9 [2·9-5·1] and 6·4 [5·1-8·0]), and musculoskeletal conditions (6·5 [3·9-11·1] and 8·0 [4·6-14·0]) when compared with siblings of the same age, although all these risks were lower for early-adolescent and young adult survivors than for childhood cancer survivors. INTERPRETATION: Early-adolescent and young adult cancer survivors had higher risks of mortality and severe and life threatening chronic health conditions than the general population. However, early-adolescent and young adult cancer survivors had lower non-recurrent, health-related SMRs and relative risks of developing grade 3-5 chronic health conditions than childhood cancer survivors, by comparison with siblings of the same age, which were most notable more than 20 years after their original cancer. These results highlight the need for long-term screening of both childhood and early-adolescent and young adult cancer survivors. FUNDING: National Cancer Institute and American Lebanese-Syrian Associated Charities.

Traditional Cardiovascular Risk Factors and Individual Prediction of Cardiovascular Events in Childhood Cancer Survivors.

BACKGROUND: Childhood cancer survivors have an increased risk of heart failure, ischemic heart disease, and stroke. They may benefit from prediction models that account for cardiotoxic cancer treatment exposures combined with information on traditional cardiovascular risk factors such as hypertension, dyslipidemia, and diabetes. METHODS: Childhood Cancer Survivor Study participants (n = 22 643) were followed through age 50 years for incident heart failure, ischemic heart disease, and stroke. Siblings (n = 5056) served as a comparator. Participants were assessed longitudinally for hypertension, dyslipidemia, and diabetes based on self-reported prescription medication use. Half the cohort was used for discovery; the remainder for replication. Models for each outcome were created for survivors ages 20, 25, 30, and 35 years at the time of prediction (n = 12 models). RESULTS: For discovery, risk scores based on demographic, cancer treatment, hypertension, dyslipidemia, and diabetes information achieved areas under the receiver operating characteristic curve and concordance statistics 0.70 or greater in 9 and 10 of the 12 models, respectively. For replication, achieved areas under the receiver operating characteristic curve and concordance statistics 0.70 or greater were observed in 7 and 9 of the models, respectively. Across outcomes, the most influential exposures were anthracycline chemotherapy, radiotherapy, diabetes, and hypertension. Survivors were then assigned to statistically distinct risk groups corresponding to cumulative incidences at age 50 years of each target outcome of less than 3% (moderate-risk) or approximately 10% or greater (high-risk). Cumulative incidence of all outcomes was 1% or less among siblings. CONCLUSIONS: Traditional cardiovascular risk factors remain important for predicting risk of cardiovascular disease among adult-age survivors of childhood cancer. These prediction models provide a framework on which to base future surveillance strategies and interventions.

Hospital admission for neurologic disorders among 5-year survivors of noncentral nervous system tumors in childhood: A cohort study within the Adult Life after Childhood Cancer in Scandinavia study.

Large, comprehensive studies of the risk for neurologic disorders among long-term survivors of noncentral nervous system (CNS) childhood cancers are lacking. Thus, the aim of our study was to assess the lifetime risk of Nordic non-CNS childhood cancer survivors for neurologic disorders. We identified 15,967 5-year survivors of non-CNS childhood cancer diagnosed in Denmark, Iceland, Finland and Sweden in 1943-2008, and 151,118 matched population comparison subjects. In-patient discharge diagnoses of neurologic disorders were used to calculate relative risks (RRs) and absolute excess risks (AERs). A neurologic disorder was diagnosed in 755 of the survivors while 370 were expected, yielding a RR of 2.0 (95% confidence interval (CI) 1.9-2.2). The highest risks were found among survivors of neuroblastoma (4.1; 95% CI 3.2-5.3) and leukemia (2.8; 95% CI 2.4-3.2). The AER decreased from 331 (278-383) excess neurologic disorders per 100,000 person-years 5-9 years after diagnosis to 82 (46-118) ≥ 20 years after diagnosis. Epilepsy was the most common diagnosis (n = 229, 1.4% of all survivors), and significantly increased risks were seen among survivors of eight out of 12 types of childhood cancer. Survivors of neuroblastoma had remarkably high risks (RR ≥ 10) for hospitalization for paralytic syndromes and hydrocephalus, while survivors of leukemia had additional high risks for dementia and encephalopathy. In conclusion, survivors of non-CNS childhood cancer are at high risk for neurologic disorders, especially within the first decade after diagnosis. Therefore, intensive follow-up to identify those who require close management is needed.

Solid organ transplantation after treatment for childhood cancer: a retrospective cohort analysis from the Childhood Cancer Survivor Study.

BACKGROUND: Serious chronic medical conditions occur in childhood cancer survivors. We aimed to investigate incidence of and risk factors for end-organ damage resulting in registration on a waiting list for or receiving a solid organ transplantation and 5-year survival following these procedures. METHODS: The Childhood Cancer Survivor Study (CCSS) is a retrospective cohort of individuals who survived at least 5 years after childhood cancer diagnosed at younger than 21 years of age, between Jan 1, 1970, and Dec 31, 1986, at one of 25 institutions in the USA. We linked data from CCSS participants treated in the USA diagnosed between Jan 1, 1970, and Dec 31, 1986 (without solid organ transplantation before cohort entry) to the Organ Procurement and Transplantation Network-a database of all US organ transplants. Eligible participants had been diagnosed with leukaemia, lymphoma, malignant CNS tumours, neuroblastoma, Wilms' tumours, and bone and soft tissue sarcomas. The two primary endpoints for each type of organ transplant were date of first registration of a transplant candidate on the waiting list for an organ and the date of the first transplant received. We also calculated the cumulative incidence of being placed on a waiting list or receiving a solid organ transplantation, hazard ratios (HRs) for identified risk factors, and 5-year survival following transplantation. FINDINGS: Of 13 318 eligible survivors, 100 had 103 solid organ transplantations (50 kidney, 37 heart, nine liver, seven lung) and 67 were registered on a waiting list without receiving a transplant (21 kidney, 25 heart, 15 liver, six lung). At 35 years after cancer diagnosis, the cumulative incidence of transplantation or being on a waiting list was 0·54% (95% CI 0·40-0·67) for kidney transplantation, 0·49% (0·36-0·62) for heart, 0·19% (0·10-0·27) for liver, and 0·10% (0·04-0·16) for lung. Risk factors for kidney transplantation were unilateral nephrectomy (HR 4·2, 95% CI 2·3-7·7), ifosfamide (24·9, 7·4-83·5), total body irradiation (6·9, 2·3-21·1), and mean kidney radiation of greater than 15 Gy (>15-20 Gy, 3·6 [1·5-8·5]; >20 Gy 4·6 [1·1-19·6]); for heart transplantation, anthracycline and mean heart radiation of greater than 20 Gy (dose-dependent, both p<0·0001); for liver transplantation, dactinomycin (3·8, 1·3-11·3) and methotrexate (3·3, 1·0-10·2); for lung transplantation, carmustine (12·3, 3·1-48·9) and mean lung radiation of greater than 10 Gy (15·6, 2·6-92·7). 5-year overall survival after solid organ transplantation was 93·5% (95% CI 81·0-97·9) for kidney transplantation, 80·6% (63·6-90·3) for heart, 27·8% (4·4-59·1) for liver, and 34·3% (4·8-68·6) for lung. INTERPRETATION: Solid organ transplantation is uncommon in ageing childhood cancer survivors. Organ-specific exposures were associated with increased solid organ transplantation incidence. Survival outcomes showed that solid organ transplantation should be considered for 5-year childhood cancer survivors with severe end-organ failure. FUNDING: US National Institute of Health, American Lebanese Syrian Associated Charities, US Health Resources and Services Administration.

Adaptations to a Generalized Radiation Dose Reconstruction Methodology for Use in Epidemiologic Studies: An Update from the MD Anderson Late Effect Group.

Epidemiologic studies that include patients who underwent radiation therapy for the treatment of cancer aim to quantify the relationship between radiotherapy and the risk of subsequent late effects. Because of the long follow-up period required to observe late effects, these studies are conducted retrospectively. The studies routinely include patients treated across numerous institutions using a wide range of technologies and represent treatments over several decades. As a result, determining the dose throughout the patient's body is uniquely challenging. Therefore, estimating doses throughout the patient's body for epidemiologic studies requires special methodologies that are generally applied to a wide range of radiotherapy techniques. Over ten years ago, the MD Anderson Late Effects Group described various dose reconstruction methods for therapeutic and diagnostic radiation exposure for epidemiologic studies. Here we provide an update to the most widely used dose reconstruction methodology for epidemiologic studies, analytical model calculations combined with a 3D age-specific computational phantom. In particular, we describe the various adaptations (and enhancements) of that methodology, as well as how they have been used in radiation epidemiology studies and may be used in future studies.

Hyperthyroidism After Radiation Therapy for Childhood Cancer: A Report from the Childhood Cancer Survivor Study.

PURPOSE: The association of hyperthyroidism with exposure to ionizing radiation is poorly understood. This study addresses the risk of hyperthyroidism in relation to incidental therapeutic radiation dose to the thyroid and pituitary glands in a large cohort of survivors of childhood cancer. METHODS AND MATERIALS: Using the Childhood Cancer Survivor Study's cohort of 5-year survivors of childhood cancer diagnosed at hospitals in the United States and Canada between 1970 and 1986, the occurrence of hyperthyroidism through 2009 was ascertained among 12,183 survivors who responded to serial questionnaires. Radiation doses to the thyroid and pituitary glands were estimated from radiation therapy records, and chemotherapy exposures were abstracted from medical records. Binary outcome regression was used to estimate prevalence odds ratios (ORs) for hyperthyroidism at 5 years from diagnosis of childhood cancer and Poisson regression to estimate incidence rate ratios (RRs) after the first 5 years. RESULTS: Survivors reported 179 cases of hyperthyroidism, of which 148 were diagnosed 5 or more years after their cancer diagnosis. The cumulative proportion of survivors diagnosed with hyperthyroidism by 30 years after the cancer diagnosis was 2.5% (95% confidence interval [CI], 2.0%-2.9%) among those who received radiation therapy. A linear relation adequately described the thyroid radiation dose response for prevalence of self-reported hyperthyroidism 5 years after cancer diagnosis (excess OR/Gy, 0.24; 95% CI, 0.06-0.95) and incidence rate thereafter (excess RR/Gy, 0.06; 95% CI, 0.03-0.14) over the dose range of 0 to 63 Gy. Neither radiation dose to the pituitary gland nor chemotherapy was associated significantly with hyperthyroidism. Radiation-associated risk remained elevated >25 years after exposure. CONCLUSIONS: Risk of hyperthyroidism after radiation therapy during childhood is positively associated with external radiation dose to the thyroid gland, with radiation-related excess risk persisting for >25 years. Neither radiation dose to the pituitary gland nor chemotherapy exposures were associated with hyperthyroidism among childhood cancer survivors through early adulthood.

Neurologic disorders in 4858 survivors of central nervous system tumors in childhood-an Adult Life after Childhood Cancer in Scandinavia (ALiCCS) study.

Background: A comprehensive overview of neurologic complications among survivors of central nervous system (CNS) tumors in childhood is lacking. We aimed to investigate the risk for these disorders in a large, population-based study with outcome measures from nationwide hospital registries. Methods: We identified 4858 five-year survivors with diagnoses of CNS tumor in childhood in Denmark, Iceland, Finland, and Sweden in 1943-2007, and 166658 matched population comparison subjects. Inpatient discharge diagnoses of neurologic disorders were used to calculate relative risks (RRs) and absolute excess risks (AERs). Results: A neurologic disorder was verified in 1309 survivors, while 92.4 were expected, yielding an overall RR of 14.2 (95% confidence interval [CI]: 13.3-15.1) and an AER of 20 hospitalizations per 1000 persons per year. The risks remained increased more than 20 years after diagnosis (RR: 6.3, 95% CI: 5.6-7.2; AER: 11, 9-12). The most frequent diagnoses were epilepsy (affecting 14.1% of all survivors) followed by hydrocephalus (9.5%) and paralytic syndromes (4.2%), with RRs of 28.7 (95% CI: 26.0-31.6), 243 (95% CI: 190-311), and 40.3 (95% CI: 33.1-49.2), respectively. Of these outcomes, 30%-40% were diagnosed prior to or synchronously with the CNS tumor. The survivors had highly increased RRs for infectious diseases of the CNS, disorders of cranial nerves, and degenerative diseases of the nervous system. Conclusions: Survivors of childhood CNS tumors are at markedly increased risk for neurologic disorders throughout their lives. Health care professionals must be aware of survivors who might benefit from preventive interventions and intensive follow-up.

Risk of Coronary Events 55 Years after Thymic Irradiation in the Hempelmann Cohort.

BACKGROUND: Studies of cancer survivors treated with older radiotherapy (RT) techniques (pre-1990s) strongly suggest that ionizing radiation to the chest increases the risk of coronary heart disease (CHD). Our goal was to evaluate the impact of more modern cardiac shielding techniques of RT on the magnitude and timing of CHD risk by studying a cohort exposed to similar levels of cardiac irradiation years ago. METHODS: Between 2004 and 2008, we re-established a population-based, longitudinal cohort of 2,657 subjects exposed to irradiation for an enlarged thymus during infancy between 1926 and 1957 and 4,388 of their non-irradiated siblings. CHD events were assessed using a mailed survey and from causes of death listed in the National Death Index. We used Poisson regression methods to compare incidence rates by irradiation status and cardiac radiation dose. Results were adjusted for the CHD risk factors of attained-age, sex, diabetes, dyslipidemia hypertension and smoking. RESULTS: Median age at time of follow-up was 57.5 years (range 41.2 - 88.8 yrs) for irradiated and non-irradiated siblings. The mean estimated cardiac dose amongst the irradiated was 1.45 Gray (range 0.17 - 20.20 Gy), with 91% receiving <3.00 Gy. During a combined 339,924 person-years of follow-up, 213 myocardial infarctions (MI) and 350 CHD events (MI, bypass surgery and angioplasty) occurred. After adjustment for attained age, gender, and other CHD risk factors, the rate ratio for MI incidence in the irradiated group was 0.98 (95%CI, 0.74 - 1.30), and for any CHD event was 1.07 (95%CI, 0.86 - 1.32). Higher radiation doses were not associated with more MIs or CHD events in this dose range, in either the crude or the adjusted analyses. CONCLUSIONS: Radiation to the heart during childhood of <3 Gy, the exposure in most of our cohort, does not increase the lifelong risk of CHD. Reducing cardiac radiation to this amount without increasing other cardiotoxic therapies may eliminate the increased CHD risk associated with radiotherapy for childhood cancer. By extension there is unlikely to be increased CHD risk from relatively higher dose imaging techniques, such as CT, because such techniques use much smaller radiation doses than received by our cohort.

Hypothyroidism after Radiation Therapy for Childhood Cancer: A Report from the Childhood Cancer Survivor Study.

While thyroid cancer risks from exposure to ionizing radiation early in life are well characterized quantitatively, the association of radiation with nonmalignant, functional thyroid disorders has been less studied. Here, we report on a risk analysis study of hypothyroidism with radiation dose to the thyroid gland and the hypothalamic-pituitary axis among survivors of childhood cancer. Utilizing data from the Childhood Cancer Survivor Study, a cohort of 14,364 five-year survivors of childhood cancer diagnosed at 26 hospitals in the U.S. and Canada between 1970 and 1986 and followed through 2009, the occurrence of hypothyroidism was ascertained among 12,015 survivors through serial questionnaires. Radiation doses to the thyroid gland and pituitary gland were estimated from radiotherapy records. Binary outcome regression was used to estimate prevalence odds ratios for hypothyroidism at five years from diagnosis of childhood cancer and Poisson regression to model incidence rate ratios (RR) after the first five years. A total of 1,193 cases of hypothyroidism were observed, 777 (65%) of which occurred five or more years after cancer diagnosis. The cumulative proportion affected with hypothyroidism (prevalence at five years after cancer diagnosis plus incidence through 30 years after cancer diagnosis) was highest among five-year survivors of Hodgkin lymphoma (32.3%; 95% CI: 29.5-34.9) and cancers of the central nervous system (17.7%; 95% CI: 15.2-20.4). The incidence rate was significantly associated with radiation dose to the thyroid and pituitary. The joint association of hypothyroidism with thyroid and pituitary dose was sub-additive for pituitary doses greater than 16 Gy. In particular, a very strong thyroid radiation dose dependence at low-to-moderate pituitary/hypothalamic doses was diminished at high pituitary doses. Radiation-related risks were higher in males than females and inversely associated with age at exposure and time since exposure but remained elevated more than 25 years after exposure. Our findings indicated that hypothyroidism was significantly associated with treatment with bleomycin (RR = 3.4; 95% CI: 1.6-7.3) and the alkylating agents cyclohexyl-chloroethyl-nitrosourea (CCNU) (RR = 3.0; 95% CI: 1.5-5.3) and cyclophosphamide (RR = 1.3; 95% CI: 1.0-1.8), with a significant dose response for CCNU ( P < 0.01). The risk of hypothyroidism among childhood cancer survivors treated with radiation depends both on direct, dose-dependent radiation-induced damage to the thyroid gland and on dose-dependent indirect effects secondary to irradiation of the hypothalamic-pituitary axis. The dose-response relationship for each site depends on dose to the other. Radiation-related risk persists for more than 25 years after treatment. Treatment with certain chemotherapy agents may increase the risk of hypothyroidism.

Perceptions of risk of infertility among male survivors of childhood cancer: A report from the Childhood Cancer Survivor Study.

BACKGROUND: The objective of the current study was to characterize and identify factors associated with perceptions of risk of infertility among adult male survivors of childhood cancer. METHODS: A total of 1233 adult male survivors from the Childhood Cancer Survivor Study who were without a history of disease recurrence or subsequent malignancy reported their perceptions of their risk of infertility compared with men never diagnosed with cancer. Survivors were a median age of 37.8 years (range, 22.0-58.7 years) and were 28.4 years from their diagnosis (range, 21.4-39.2 years). Multivariable logistic regression evaluated factors associated with perceptions of risk. RESULTS: Overall, 35.9% of the survivors (443 of 1233 survivors) reported perceptions of their risk of infertility that were discordant with their actual risk based on previous cancer treatment exposures. Discordant perceptions were equally common among men exposed to gonadotoxic therapies (36.3%; 311 of 857 men) and those with no history of gonadotoxic exposure (35.1%; 132 of 376 men). Survivors who fathered children (odds ratio [OR], 4.14; 95% confidence interval [95% CI], 2.74-6.24), had no survivor-focused health care (OR, 3.07; 95% CI, 1.57-5.99), were nonwhite (OR, 2.28; 95% CI, 1.10-4.75), and were of lower income were more likely to report no increased risk of infertility after gonadotoxic treatment. Perceptions of increased risk of infertility among men with no history of gonadotoxic treatment were predicted by never having fathered a child (OR, 1.88; 95% CI, 1.17-3.03), recent participation in survivor-focused health care (OR, 2.11; 95% CI, 1.01-4.42), and higher educational achievement. CONCLUSIONS: Many male survivors of childhood cancer are unaware of how their cancer treatments could impact their reproductive health, underscoring the need for all patients to receive education regarding their risk of infertility throughout the continuum of cancer care. Cancer 2018;124:2447-55. © 2018 American Cancer Society.

Nonsurgical premature menopause and reproductive implications in survivors of childhood cancer: A report from the Childhood Cancer Survivor Study.

BACKGROUND: Survivors of childhood cancer are at risk of nonsurgical premature menopause (NSPM). To the authors' knowledge, risk factors for NSPM and its impact on reproduction remain poorly defined. METHODS: The menopausal status of 2930 survivors diagnosed between 1970 and 1986 (median age, 6 years [range, birth-20 years]) who were aged > 18 years at the time of the current study (median age, 35 years [range, 18-58 years]) was compared with 1399 siblings. NSPM was defined as the cessation of menses ≥6 months in duration occurring 5 years after diagnosis and before age 40 that was not due to pregnancy, surgery, or medications. Among survivors, multivariable logistic regression identified risk factors for NSPM. Pregnancy and live birth rates were compared between survivors with and without NSPM. RESULTS: A total of 110 survivors developed NSPM (median age, 32 years [range, 16-40 years]), with a prevalence at age 40 years of 9.1% (95% confidence interval [95% CI], 4.9%-17.2%); the odds ratio (OR) was 10.5 (95% CI, 4.2-26.3) compared with siblings. Independent risk factors included exposure to a procarbazine dose ≥4000 mg/m2 (OR, 8.96 [95% CI, 5.02-16.00]), any dose of ovarian radiation (OvRT) (OvRT < 500 cGy: OR, 2.73 [95% CI, 1.33-5.61] and OvRT ≥ 500 cGy: OR, 8.02 [95% CI, 2.81-22.85]; referent RT, 0), and receipt of a stem cell transplantation (OR, 6.35; 95% CI, 1.19-33.93). Compared with survivors without NSPM, those who developed NSPM were less likely to ever be pregnant (rate ratio, 0.49; 95% CI, 0.27-0.80) or to have a live birth (rate ratio, 0.42; 95% CI, 0.19-0.79) between ages 31 and 40 years. CONCLUSIONS: Survivors of childhood cancer are at risk of NSPM associated with lower rates of live birth in their 30s. Those at risk should consider fertility preservation if they anticipate delaying childbearing. Cancer 2018;124:1044-52. © 2018 American Cancer Society.

Longitudinal assessment of late-onset neurologic conditions in survivors of childhood central nervous system tumors: a Childhood Cancer Survivor Study report.

Background: Survivors of childhood central nervous system (CNS) tumors experience high rates of treatment-related neurologic sequelae. Whether survivors continue to be at increased risk for new events as they age is unknown. Methods: Adverse neurologic health conditions in 5-year survivors of CNS tumors from the Childhood Cancer Survivor Study (n = 1876) were evaluated longitudinally at a median 23.0 years from diagnosis (range, 5.1-38.9), median age at last evaluation 30.3 years (range, 6.1-56.4). Multivariable regression estimated hazard ratios (HRs) and 95% CIs. Results: From 5 to 30 years post diagnosis, cumulative incidence increased for seizures from 27% to 41%, motor impairment 21% to 35%, and hearing loss 9% to 23%. Risks were elevated compared with siblings (eg, seizures HR: 12.7; 95% CI: 9.6-16.7; motor impairment HR: 7.6; 95% CI: 5.8-9.9; hearing loss HR: 18.4; 95% CI: 13.1-25.9). Regional brain doses of radiation therapy were associated with development of new deficits (eg, frontal ≥50 Gy and motor impairment HR: 2.0; 95% CI: 1.2-3.4). Increased risk for motor impairment was also associated with tumor recurrence (HR: 2.6; 95% CI: 1.8-3.8), development of a meningioma (HR: 2.3; 95% CI: 0.9-5.4), and stroke (HR: 14.9; 95% CI: 10.4-21.4). Seizure risk was doubled by recurrence (HR: 2.3; 95% CI: 1.6-3.2), meningioma (HR: 2.6; 95% CI: 1.1-6.5), and stroke (HR: 2.0; 95% CI: 1.1-3.4). Conclusions: CNS tumor survivors remain at risk for new-onset adverse neurologic events across their lifespans at a rate greater than siblings. Cranial radiation, stroke, tumor recurrence, and development of meningioma were independently associated with late-onset adverse neurologic sequelae.

Chromosomal Abnormalities in Offspring of Young Cancer Survivors: A Population-Based Cohort Study in Denmark.

To examine whether cancer survivors diagnosed before age 35 years are more likely to have offspring with chromosomal abnormalities than their siblings, chromosomal abnormalities were determined in a population-based cohort of 14 611 offspring (14 580 live-born children and 31 fetuses) of 8945 Danish cancer survivors and 40 859 offspring (40 794 live-born children and 65 fetuses) of 19 536 siblings. Chromosomal abnormalities include numeric and structural abnormalities. Odds ratios were estimated by multiple logistic regression models comparing the risk of chromosomal abnormalities among survivors' offspring with that in siblings' offspring. In a subgroup of survivors with gonadal radiation doses (mean = 0.95 Gy for males and 0.91 Gy for females), no indication of a dose response was found. Overall, no increased risk of chromosomal abnormalities among survivors' offspring was observed compared with their siblings' offspring (odds ratio = 0.99, 95% confidence interval = 0.67 to 1.44, two-sided P = .94), with similar risk between male and female survivors. Cancer survivors were not more likely than their siblings to have children with a chromosomal abnormality.

Prediction of Ischemic Heart Disease and Stroke in Survivors of Childhood Cancer.

Purpose We aimed to predict individual risk of ischemic heart disease and stroke in 5-year survivors of childhood cancer. Patients and Methods Participants in the Childhood Cancer Survivor Study (CCSS; n = 13,060) were observed through age 50 years for the development of ischemic heart disease and stroke. Siblings (n = 4,023) established the baseline population risk. Piecewise exponential models with backward selection estimated the relationships between potential predictors and each outcome. The St Jude Lifetime Cohort Study (n = 1,842) and the Emma Children's Hospital cohort (n = 1,362) were used to validate the CCSS models. Results Ischemic heart disease and stroke occurred in 265 and 295 CCSS participants, respectively. Risk scores based on a standard prediction model that included sex, chemotherapy, and radiotherapy (cranial, neck, and chest) exposures achieved an area under the curve and concordance statistic of 0.70 and 0.70 for ischemic heart disease and 0.63 and 0.66 for stroke, respectively. Validation cohort area under the curve and concordance statistics ranged from 0.66 to 0.67 for ischemic heart disease and 0.68 to 0.72 for stroke. Risk scores were collapsed to form statistically distinct low-, moderate-, and high-risk groups. The cumulative incidences at age 50 years among CCSS low-risk groups were < 5%, compared with approximately 20% for high-risk groups ( P < .001); cumulative incidence was only 1% for siblings ( P < .001 v low-risk survivors). Conclusion Information available to clinicians soon after completion of childhood cancer therapy can predict individual risk for subsequent ischemic heart disease and stroke with reasonable accuracy and discrimination through age 50 years. These models provide a framework on which to base future screening strategies and interventions.

Genome-Wide Association Study to Identify Susceptibility Loci That Modify Radiation-Related Risk for Breast Cancer After Childhood Cancer.

Background: Childhood cancer survivors treated with chest-directed radiotherapy have substantially elevated risk for developing breast cancer. Although genetic susceptibility to breast cancer in the general population is well studied, large-scale evaluation of breast cancer susceptibility after chest-directed radiotherapy for childhood cancer is lacking. Methods: We conducted a genome-wide association study of breast cancer in female survivors of childhood cancer, pooling two cohorts with detailed treatment data and systematic, long-term follow-up: the Childhood Cancer Survivor Study and St. Jude Lifetime Cohort. The study population comprised 207 survivors who developed breast cancer and 2774 who had not developed any subsequent neoplasm as of last follow-up. Genotyping and subsequent imputation yielded 16 958 466 high-quality variants for analysis. We tested associations in the overall population and in subgroups stratified by receipt of lower than 10 and 10 or higher gray breast radiation exposure. We report P values and pooled per-allele risk estimates from Cox proportional hazards regression models. All statistical tests were two-sided. Results: Among survivors who received 10 or higher gray breast radiation exposure, a locus on 1q41 was associated with subsequent breast cancer risk (rs4342822, nearest gene PROX1 , risk allele frequency in control subjects [RAF controls ] = 0.46, hazard ratio = 1.92, 95% confidence interval = 1.49 to 2.44, P = 7.09 × 10 -9 ). Two rare variants also showed potentially promising associations (breast radiation ≥10 gray: rs74949440, 11q23, TAGLN , RAF controls = 0.02, P = 5.84 × 10 -8 ; <10 gray: rs17020562, 1q32.3, RPS6KC1 , RAF controls = 0.0005, P = 6.68 × 10 -8 ). Associations were restricted to these dose subgroups, with consistent findings in the two survivor cohorts. Conclusions: Our study provides strong evidence that germline genetics outside high-risk syndromes could modify the effect of radiation exposure on breast cancer risk after childhood cancer.

Longitudinal follow-up of adult survivors of Ewing sarcoma: A report from the Childhood Cancer Survivor Study.

BACKGROUND: Ewing sarcoma survivors (ESSs) are at increased risk for treatment-related complications. The incidence of treatment-related morbidity and late mortality with aging is unknown. METHODS: This study reports survival probabilities, estimated with the Kaplan-Meier method, and the cumulative incidence of cause-specific mortality and chronic conditions among ESSs in the Childhood Cancer Survivor Study who were treated between 1970 and 1986. Piecewise exponential models were used to estimate relative rates (RRs) and 95% confidence intervals (CIs) for these outcomes. Chronic conditions were graded with the Common Terminology Criteria for Adverse Events (version 4.03). RESULTS: Among 404 5-year ESSs (median age at last follow-up, 34.8 years; range, 9.1-54.8 years), the 35-year survival rate was 70% (95% CI, 66%-74%). Late recurrence (cumulative incidence at 35 years, 15.1%) was the most common cause of death, and it was followed by treatment-related causes (11.2%). There were 53 patients with subsequent neoplasms (SNs; cumulative incidence at 35 years, 24.0%), and 38 were malignant (14.3% at 35 years). The standardized incidence ratios were 377.1 (95% CI, 172.1-715.9) for osteosarcoma, 28.9 (95% CI, 3.2-104.2) for acute myeloid leukemia, 14.9 (95% CI, 7.9-25.5) for breast cancer, and 13.1 (95% CI, 4.8-28.5) for thyroid cancer. Rates of chronic conditions were highest for musculoskeletal (RR, 18.1; 95% CI, 12.8-25.7) and cardiac complications (RR, 1.8; 95% CI, 1.4-2.3). Thirty-five years after the diagnosis, the cumulative incidences of any chronic conditions and 2 or more chronic conditions were 84.6% (95% CI, 80.4%-88.8%) and 73.8% (95% CI, 67.8%-79.9%), respectively. CONCLUSIONS: With extended follow-up, ESSs' risk for late mortality and SNs does not plateau. Treatment-related chronic conditions develop years after therapy, and this supports the need for lifelong follow-up. Cancer 2017;123:2551-60. © 2017 American Cancer Society.