Trans-Ancestral Genetic Risk Factors for Treatment-Related Type 2 Diabetes Mellitus in Survivors of Childhood Cancer.

PURPOSE: Type 2 diabetes mellitus (T2D) is a prevalent long-term complication of treatment in survivors of childhood cancer, with marked racial/ethnic differences in burden. In this study, we investigated trans-ancestral genetic risks for treatment-related T2D. PATIENTS AND METHODS: Leveraging whole-genome sequencing data from the St Jude Lifetime Cohort (N = 3,676, 304 clinically ascertained cases), we conducted ancestry-specific genome-wide association studies among survivors of African and European genetic ancestry (AFR and EUR, respectively) followed by trans-ancestry meta-analysis. Trans-/within-ancestry replication including data from the Childhood Cancer Survivor Study (N = 5,965) was required for prioritization. Three external general population T2D polygenic risk scores (PRSs) were assessed, including multiancestry PRSs. Treatment risk effect modification was evaluated for prioritized loci. RESULTS: Four novel T2D risk loci showing trans-/within-ancestry replication evidence were identified, with three loci achieving genome-wide significance (P < 5 × 10-8). Among these, common variants at 5p15.2 (LINC02112), 2p25.3 (MYT1L), and 19p12 (ZNF492) showed evidence of modifying alkylating agent-related T2D risk in both ancestral groups, but showed disproportionately greater risk in AFR survivors (AFR odds ratios [ORs], 3.95-17.81; EUR ORs, 2.37-3.32). In survivor-specific RNA-sequencing data (N = 207), the 19p12 locus variant was associated with greater ZNF492 expression dysregulation after exposures to alkylators. Elevated T2D risks across ancestry groups were only observed with increasing values for multiancestry T2D PRSs and were especially increased among survivors treated with alkylators (top v bottom quintiles: ORAFR, 20.18; P = .023; OREUR, 13.44; P = 1.3 × 10-9). CONCLUSION: Our findings suggest therapy-related genetic risks contribute to the increased T2D burden among non-Hispanic Black childhood cancer survivors. Additional study of how therapy-related genetic susceptibility contributes to this disparity is needed.

St. Jude Survivorship Portal: sharing and analyzing large clinical and genomic datasets from pediatric cancer survivors.

Childhood cancer survivorship studies generate comprehensive datasets comprising demographic, diagnosis, treatment, outcome, and genomic data from survivors. To broadly share this data, we created the St. Jude Survivorship Portal (https://survivorship.stjude.cloud), the first data portal for sharing, analyzing, and visualizing pediatric cancer survivorship data. Over 1,600 phenotypic variables and 400 million genetic variants from over 7,700 childhood cancer survivors can be explored on this free, open-access portal. Summary statistics of variables are computed on-the-fly and visualized through interactive and customizable charts. Survivor cohorts can be customized and/or divided into groups for comparative analysis. Users can also seamlessly perform cumulative incidence and regression analyses on the stored survivorship data. Using the portal, we explored the ototoxic effects of platinum-based chemotherapy, uncovered a novel association between mental health, age, and limb amputation, and discovered a novel haplotype in MAGI3 strongly associated with cardiomyopathy specifically in survivors of African ancestry.

Associations of seven measures of biological age acceleration with frailty and all-cause mortality among adult survivors of childhood cancer in the St. Jude Lifetime Cohort.

Survivors of childhood cancer may experience accelerated biological aging, resulting in premature frailty and death. We used seven measures of biological age in the St. Jude Lifetime (SJLIFE) Cohort to compare biological age acceleration between the SJLIFE Cohort and the third United States National Health and Nutrition Examination Survey controls, explore trajectories of biological age according to cancer treatment and type, and test associations of biological age acceleration with frailty and death (mean follow-up of 26.5 years) among survivors. Survivors of cancer aged 5% faster per year and measured, on average, 0.6-6.44 years biologically older compared to controls and 5-16 years biologically older compared to age-matched individuals at the population level. Survivors treated with hematopoietic cell transplant and vinca alkaloid chemotherapy evidenced the fastest trajectories of biological aging. Biologically, older and faster-aging survivors consistently and robustly had a higher risk of frailty and died earlier than those with slower biological aging, suggesting a potential opportunity to intervene on excess aging.

Quantitative computed tomography analysis of body composition changes in paediatric patients with acute lymphoblastic leukaemia.

Children with acute lymphoblastic leukaemia (ALL) are at risk for obesity and cardiometabolic diseases. To gain insight into body composition changes among children with ALL, we assessed quantitative computed tomography (QCT) data for specific body compartments (subcutaneous adipose tissue [SAT], visceral adipose tissue [VAT], total adipose tissue [TAT], lean tissue [LT], LT/TAT and VAT/SAT at lumbar vertebrae L1 and L2) at diagnosis and at off-therapy for 189 children with ALL and evaluated associations between body mass index (BMI) Z-score and clinical characteristics. BMI Z-score correlated positively with SAT, VAT and TAT and negatively with LT/TAT and VAT/SAT. At off-therapy, BMI Z-score, SAT, VAT and TAT values were higher than at diagnosis, but LT, LT/TAT and VAT/SAT were lower. Patients aged ≥10 years at diagnosis had higher SAT, VAT and TAT and lower LT and LT/TAT than patients aged 2.0-9.9 years. Female patients had lower LT and LT/TAT than male patients. Black patients had less VAT than White patients. QCT analysis showed increases in adipose tissue and decreases in LT during ALL therapy when BMI Z-scores increased. Early dietary and physical therapy interventions should be considered, particularly for patients at risk for obesity.

Prediabetes and Associated Risk of Cardiovascular Events and Chronic Kidney Disease Among Adult Survivors of Childhood Cancer in the St Jude Lifetime Cohort.

PURPOSE: Little is known about the prevalence of prediabetes and associated risk of cardiovascular events and chronic kidney disease (CKD) with this reversable condition in survivors. METHODS: Prevalence of prediabetes (fasting plasma glucose 100-125 mg/dL or hemoglobin A1c 5.7%-6.4%) and diabetes was clinically assessed in 3,529 adults ≥5 years from childhood cancer diagnosis and 448 controls stratified by age. Cox proportional hazards regression estimated progression from prediabetes to diabetes, and risk of future cardiac events, stroke, CKD, and death. RESULTS: Among survivors, median age 30 years (IQR, 18-65), and the prevalence of prediabetes was 29.2% (95% CI, 27.7 to 30.7) versus 18.1% (14.5 to 21.6) in controls and of diabetes was 6.5% (5.7 to 7.3) versus 4.7% (2.7 to 6.6). By age 40-49 years, more than half of the survivors had prediabetes (45.5%) or diabetes (14.0%). Among 695 survivors with prediabetes and longitudinal follow-up, 68 (10%; median follow-up, 5.1 years) progressed to diabetes. After adjustment for demographic factors and body composition, risk of progression was associated with radiation exposure to the pancreatic tail ≥10 Gy (hazard ratio [HR], 2.7 [95% CI, 1.1 to 6.8]) and total-body irradiation (4.4 [1.5 to 13.1]). Compared with survivors with normal glucose control, adjusting for relevant treatment exposures, those with prediabetes were at increased risk of future myocardial infarction (HR, 2.4 [95% CI, 1.2 to 4.8]) and CKD (2.9 [1.04 to 8.15]), while those with diabetes were also at increased risk of future cardiomyopathy (3.8 [1.4 to 10.5]) or stroke (3.4 [1.3 to 8.9]). CONCLUSION: Prediabetes is highly prevalent in adult survivors of childhood cancer and independently associated with an increased risk of future cardiovascular and kidney complications. Prediabetes, a modifiable risk factor among childhood cancer survivors, represents a new target for intervention that may prevent subsequent morbidity and mortality.

Trends in physical functioning in acute lymphoblastic leukemia and non-Hodgkin lymphoma survivors across three decades.

PURPOSE: The impact of changes in therapy for childhood acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL) on the prevalence of physical performance limitations and participation restrictions among survivors is unknown. We aimed to describe the prevalence of reduced function among ALL and NHL survivors by treatment era. METHODS: Participants included survivors of childhood ALL and NHL, and a cohort of their siblings, participating in the Childhood Cancer Survivor Study (CCSS). Physical function was measured using questionnaire. The prevalence of reduced function was compared to siblings using generalized estimating equations, overall and stratified by treatment decade. Associations between organ system-specific chronic conditions (CTCAE v4.03) and function were also evaluated. RESULTS: Among 6511 survivors (mean age 25.9 years (standard deviation 6.5)) and 4127 siblings, risk of performance limitations (15.2% vs. 12.5%, prevalence ratio [PR] = 1.5, 95%CI = 1.3-1.6), restrictions in personal care (2.0% vs. 0.6%, PR = 3.1, 95% CI = 2.0-4.8), routine activities (5.5% vs. 1.6%, PR = 3.6, 95% CI = 2.7-4.8), and work/school attendance (8.8% vs. 2.1%, PR = 4.5, 95% CI = 3.6-5.7) was increased in survivors vs. siblings. The prevalence of survivors reporting reduced function did not decrease between the 1970s and 1990s. The presence of neurological and cardiovascular conditions was associated with reduced function regardless of treatment decade. CONCLUSIONS: Despite changes in therapy, the prevalence of poor physical function remained constant between the 1970s and 1990s. The CCSS clinical trial registration number is NCT01120353 (registered May 6, 2010). IMPLICATIONS FOR CANCER SURVIVORS: Our findings support screening for reduced physical function so that early interventions to improve physical performance and mitigate chronic disease can be initiated.

Trans-ancestral genetic study of diabetes mellitus risk in survivors of childhood cancer: a report from the St. Jude Lifetime Cohort and the Childhood Cancer Survivor Study.

Type 2 diabetes mellitus (T2D) is an established late effect of treatment for childhood cancer. Leveraging detailed cancer treatment and whole-genome sequencing data among survivors of childhood cancer of European (EUR) and African (AFR) genetic ancestry in the St. Jude Lifetime Cohort (N=3,676; 304 cases), five novel diabetes mellitus (DM) risk loci were identified with independent trans-/within-ancestry replication, including in 5,965 survivors of the Childhood Cancer Survivor Study. Among these, common risk variants at 5p15.2 ( LINC02112 ), 2p25.3 ( MYT1L ), and 19p12 ( ZNF492 ) modified alkylating agent-related risks across ancestry groups, but AFR survivors with risk alleles experienced disproportionately greater risk of DM (AFR, variant ORs: 3.95-17.81; EUR, variant ORs: 2.37-3.32). Novel risk locus XNDC1N was identified in the first genome-wide DM rare variant burden association analysis in survivors (OR=8.65, 95% CI: 3.02-24.74, P=8.1×10 -6 ). Lastly, a general-population 338-variant multi-ancestry T2D polygenic risk score was informative for DM risk in AFR survivors, and showed elevated DM odds after alkylating agent exposures (quintiles: combined OR EUR =8.43, P=1.1×10 -8 ; OR AFR =13.85, P=0.033). This study supports future precision diabetes surveillance/survivorship care for all childhood cancer survivors, including those with AFR ancestry.

Cancer-Related Worry as a Predictor of 5-yr Physical Activity Level in Childhood Cancer Survivors.

PURPOSE: Cancer-related worry (CRW; concerns related to cancer and its late effects) is prevalent among childhood cancer survivors. Elevated CRW has been associated with self-reported suboptimal physical activity. The aim of this investigation was to describe associations between CRW and objectively assessed physical activity in childhood cancer survivors. METHODS: CRW was assessed at a baseline evaluation using six survey items. Weekly minutes of moderate and vigorous physical activity were captured by actigraphy 5.25 (3.8-8.0) yr later. Factor analysis was used to identify types of worry; multiple regression determined independent associations between CRW and moderate and vigorous physical activity adjusting for sex, race, diagnosis, age at baseline, anxiety level at baseline, self-reported physical activity at baseline, and pain interference at baseline. RESULTS: Participants ( n = 1223) were an average of 30.9 (SD, 6.9) yr at baseline and 36.1 (SD, 7.1) yr at follow-up. Thirty-seven percent were survivors of leukemia, 26% of non-CNS solid tumors, 19% of lymphoma, 11% of CNS tumors, and 6% of other malignancies. Two types of CRW were identified: "body-focused" and "general fear." Body-focused CRW ( ß = -19.6, P = 0.012), endorsing pain interference ( ß = -27.7, P = 0.002) at baseline, and having a diagnosis of CNS tumor ( ß = -41.3, P = 0.0003) or non-CNS solid tumor ( ß = -19.4, P = 0.02) were negatively associated with physical activity at follow-up. CONCLUSIONS: CRW related to bodily function and appearance is associated with decreased physical activity. Clinicians should consider the potential negative impact of CRW on physical activity levels and provide behavioral counseling.

Dynamics of Age- versus Therapy-Related Clonal Hematopoiesis in Long-term Survivors of Pediatric Cancer.

We present the first comprehensive investigation of clonal hematopoiesis (CH) in 2,860 long-term survivors of pediatric cancer with a median follow-up time of 23.5 years. Deep sequencing over 39 CH-related genes reveals mutations in 15% of the survivors, significantly higher than the 8.5% in 324 community controls. CH in survivors is associated with exposures to alkylating agents, radiation, and bleomycin. Therapy-related CH shows significant enrichment in STAT3, characterized as a CH gene specific to survivors of Hodgkin lymphoma, and TP53. Single-cell profiling of peripheral blood samples revealed STAT3 mutations predominantly present in T cells and contributed by SBS25, a mutational signature associated with procarbazine exposure. Serial sample tracking reveals that larger clone size is a predictor for future expansion of age-related CH clones, whereas therapy-related CH remains stable decades after treatment. These data depict the distinct dynamics of these CH subtypes and support the need for longitudinal monitoring to determine the potential contribution to late effects. SIGNIFICANCE: This first comprehensive CH analysis in long-term survivors of pediatric cancer presents the elevated prevalence and therapy exposures/diagnostic spectrum associated with CH. Due to the contrasting dynamics of clonal expansion for age-related versus therapy-related CH, longitudinal monitoring is recommended to ascertain the long-term effects of therapy-induced CH in pediatric cancer survivors. See related commentary by Collord and Behjati, p. 811. This article is highlighted in the In This Issue feature, p. 799.

Genome-wide association study of posttraumatic stress disorder among childhood cancer survivors: results from the Childhood Cancer Survivor Study and the St. Jude Lifetime Cohort.

Genetic influence shapes who develops posttraumatic stress disorder (PTSD) after traumatic events. However, the genetic variants identified for PTSD may in fact be associated with traumatic exposures (e.g., interpersonal violence), which appear heritable as well. Childhood cancer survivors (CCS) are at risk for PTSD, but genetic influences affecting cancer are unlikely to overlap with those affecting PTSD. This offers a unique opportunity to identify variants specific to PTSD risk. In a genome-wide association study (GWAS), 3984 5-year survivors of childhood cancer of European-ancestry from the Childhood Cancer Survivor Study (CCSS) were evaluated for discovery and 1467 survivors from the St. Jude Lifetime (SJLIFE) cohort for replication. Childhood cancer-related PTSD symptoms were assessed using the Posttraumatic Stress Diagnostic Scale in CCSS. GWAS was performed in CCSS using logistic regression and lead markers were replicated/meta-analyzed using SJLIFE. Cross-associations of identified loci were examined between CCS and the general population. PTSD criteria were met for 671 participants in CCSS and 161 in SJLIFE. Locus 10q26.3 was significantly associated with PTSD (rs34713356, functionally mapped to ECHS1, P = 1.36 × 10-8, OR 1.57), and was replicated in SJLIFE (P = 0.047, OR 1.37). Variants in locus 6q24.3-q25.1 reached marginal significance (rs9390543, SASH1, P = 3.56 × 10-6, OR 0.75) in CCSS and significance when meta-analyzing with SJLIFE (P = 2.02 × 10-8, OR 0.75). Both loci were exclusively associated with PTSD in CCS rather than PTSD/stress-related disorders in general population (P-for-heterogeneity < 5 × 10-6). Our CCS findings support the role of genetic variation in PTSD development and may provide implications for understanding PTSD heterogeneity.

Genetic risk score enhances the risk prediction of severe obesity in adult survivors of childhood cancer.

Adult survivors of childhood cancer have high rates of obesity, which, in combination with the cardiotoxic effects of specific cancer therapies, places them at high risk for cardiovascular morbidity. Here we show the contribution of genetic risk scores (GRSs) to increase prediction of those survivors of childhood cancer who are at risk for severe obesity (body mass index ≥40 kg m-2) as an adult. Among 2,548 individuals of European ancestry from the St. Jude Lifetime Cohort Study who were 5-year survivors of childhood cancer, the GRS was found to be associated with 53-fold-higher odds of severe obesity. Addition of GRSs to risk prediction models based on cancer treatment exposures and lifestyle factors significantly improved model prediction (area under the curve increased from 0.68 to 0.75, resulting in the identification of 4.3-times more high-risk survivors), which was independently validated in 6,064 individuals from the Childhood Cancer Survivor Study. Genetic predictors improve identification of patients who could benefit from heightened surveillance and interventions to mitigate the risk of severe obesity and associated cardio-metabolic complications.

Contribution of Genome-Wide Polygenic Score to Risk of Coronary Artery Disease in Childhood Cancer Survivors.

Background: Adverse cardiovascular outcomes such as coronary artery disease (CAD) are the leading noncancer causes of morbidity and mortality among childhood cancer survivors. Objectives: The aim of this study was to assess the role of a genome-wide polygenic score (GPS) for CAD, well validated in the general population, and its interplay with cancer-related risk factors among childhood cancer survivors. Methods: In a cohort study of 2,472 5-year childhood cancer survivors from the St. Jude Lifetime Cohort, the association between the GPS and the risk of CAD was performed using Cox regression models adjusted for age at cancer diagnosis, sex, cumulative dose of anthracyclines, and mean heart radiation dose. Results: Among survivors of European ancestry, the GPS was significantly associated with the risk of CAD (HR per 1 SD of the GPS: 1.25; 95% CI: 1.04-1.49; P = 0.014). Compared with the first tertile, survivors in the upper tertile had a greater risk of CAD (1.51-fold higher HR of CAD [95% CI: 0.96-2.37; P = 0.074]), although the difference was not statistically significant. The GPS-CAD association was stronger among survivors diagnosed with cancer at age <10 years exposed to >25 Gy heart radiation (HR top vs. bottom tertile of GPS: 15.49; 95% CI: 5.24-45.52; P trend = 0.005) but not among those diagnosed at age ≥10 years (P trend ≥ 0.77) and not among those diagnosed at age <10 years exposed to ≤25 Gy heart radiation (P trend = 0.23). Among high-risk survivors, defined by an estimated relative hazard ≥3.0 from fitted Cox models including clinical risk factors alone, the cumulative incidence of CAD at 40 years from diagnosis was 29% (95% CI: 13%-45%). After incorporating the GPS into the model, the cumulative incidence increased to 48% (95% CI: 26%-69%). Conclusions: Childhood cancer survivors are at risk for premature CAD. A GPS may help identify those who may benefit from targeted screening and personalized preventive interventions.

A Novel Locus on 6p21.2 for Cancer Treatment-Induced Cardiac Dysfunction Among Childhood Cancer Survivors.

BACKGROUND: Adult survivors of childhood cancer are at increased risk of cardiac late effects. METHODS: Using whole-genome sequencing data from 1870 survivors of European ancestry in the St. Jude Lifetime Cohort (SJLIFE) study, genetic variants were examined for association with ejection fraction (EF) and clinically assessed cancer therapy-induced cardiac dysfunction (CCD). Statistically significant findings were validated in 301 SJLIFE survivors of African ancestry and 4020 survivors of European ancestry from the Childhood Cancer Survivor Study. All statistical tests were 2-sided. RESULTS: A variant near KCNK17 showed genome-wide significant association with EF (rs2815063-A: EF reduction = 1.6%; P = 2.1 × 10-8) in SJLIFE survivors of European ancestry, which replicated in SJLIFE survivors of African ancestry (EF reduction = 1.5%; P = .004). The rs2815063-A also showed a 1.80-fold (P = .008) risk of severe or disabling or life-threatening CCD and replicated in 4020 Childhood Cancer Survivor Study survivors of European ancestry (odds ratio = 1.40; P = .04). Notably, rs2815063-A was specifically associated among survivors exposed to doxorubicin only, with a stronger effect on EF (3.3% EF reduction) and CCD (2.97-fold). Whole blood DNA methylation data in 1651 SJLIFE survivors of European ancestry showed statistically significant correlation of rs2815063-A with dysregulation of KCNK17 enhancers (false discovery rate <5%), which replicated in 263 survivors of African ancestry. Consistently, the rs2815063-A was associated with KCNK17 downregulation based on RNA sequencing of 75 survivors. CONCLUSIONS: Leveraging the 2 largest cohorts of childhood cancer survivors in North America and survivor-specific polygenomic functional data, we identified a novel risk locus for CCD, which showed specificity with doxorubicin-induced cardiac dysfunction and highlighted dysregulation of KCNK17 as the likely molecular mechanism underlying this genetic association.

Leveraging Therapy-Specific Polygenic Risk Scores to Predict Restrictive Lung Defects in Childhood Cancer Survivors.

Therapy-related pulmonary complications are among the leading causes of morbidity among long-term survivors of childhood cancer. Restrictive ventilatory defects (RVD) are prevalent, with risks increasing after exposures to chest radiotherapy and radiomimetic chemotherapies. Using whole-genome sequencing data from 1,728 childhood cancer survivors in the St. Jude Lifetime Cohort Study, we developed and validated a composite RVD risk prediction model that integrates clinical profiles and polygenic risk scores (PRS), including both published lung phenotype PRSs and a novel survivor-specific pharmaco/radiogenomic PRS (surPRS) for RVD risk reflecting gene-by-treatment (GxT) interaction effects. Overall, this new therapy-specific polygenic risk prediction model showed multiple indicators for superior discriminatory accuracy in an independent data set. The surPRS was significantly associated with RVD risk in both training (OR = 1.60, P = 3.7 × 10-10) and validation (OR = 1.44, P = 8.5 × 10-4) data sets. The composite model featuring the surPRS showed the best discriminatory accuracy (AUC = 0.81; 95% CI, 0.76-0.87), a significant improvement (P = 9.0 × 10-3) over clinical risk scores only (AUC = 0.78; 95% CI: 0.72-0.83). The odds of RVD in survivors in the highest quintile of composite model-predicted risk was ∼20-fold higher than those with median predicted risk or less (OR = 20.01, P = 2.2 × 10-16), exceeding the comparable estimate considering nongenetic risk factors only (OR = 9.20, P = 7.4 × 10-11). Inclusion of genetic predictors also selectively improved risk stratification for pulmonary complications across at-risk primary cancer diagnoses (AUCclinical = 0.72; AUCcomposite = 0.80, P = 0.012). Overall, this PRS approach that leverages GxT interaction effects supports late effects risk prediction among childhood cancer survivors. SIGNIFICANCE: This study develops a therapy-specific polygenic risk prediction model to more precisely identify childhood cancer survivors at high risk for pulmonary complications, which could help improve risk stratification for other late effects.

Blood DNA methylation signatures are associated with social determinants of health among survivors of childhood cancer.

Social epigenomics is an emerging field in which social scientist collaborate with computational biologists, especially epigeneticists, to address the underlying pathway for biological embedding of life experiences. This social epigenomics study included long-term childhood cancer survivors enrolled in the St. Jude Lifetime Cohort. DNA methylation (DNAm) data were generated using the Illumina EPIC BeadChip, and three social determinants of health (SDOH) factors were assessed: self-reported educational attainment, personal income, and an area deprivation index based on census track data. An epigenome-wide association study (EWAS) was performed to evaluate the relation between DNAm at each 5'-cytosine-phosphate-guanine-3' (CpG) site and each SDOH factor based on multivariable linear regression models stratified by ancestry (European ancestry, n = 1,618; African ancestry, n = 258). EWAS among survivors of European ancestry identified 130 epigenome-wide significant SDOH-CpG associations (P < 9 × 10-8), 25 of which were validated in survivors of African ancestry (P < 0.05). Thirteen CpGs were associated with all three SDOH factors and resided at pleiotropic loci in cigarette smoking-related genes (e.g., CLDND1 and CPOX). After accounting for smoking and body mass index, these associations remained significant with attenuated effect sizes. Seven of 13 CpGs were associated with gene expression level based on 57 subsamples with blood RNA sequencing data available. In conclusion, DNAm signatures, many resembling the effect of tobacco use, were associated with SDOH factors among survivors of childhood cancer, thereby suggesting that biologically distal SDOH factors influence health behaviours or related factors, the epigenome, and subsequently survivors' health.

Primary hypothyroidism in childhood cancer survivors: Prevalence, risk factors, and long-term consequences.

BACKGROUND: Data on primary hypothyroidism and its long-term impact on the health, cognition, and quality of life (QOL) of childhood cancer survivors are limited. This study examined the prevalence of and risk factors for primary hypothyroidism and its associations with physical, neurocognitive, and psychosocial outcomes. METHODS: This was a retrospective study with a cross-sectional health outcome analysis of an established cohort comprising 2965 survivors of childhood cancer (52.8% male; median current age, 30.9 years, median time since cancer diagnosis, 22.3 years). Multivariable logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs) for associations between primary hypothyroidism and cancer-related risk factors, cardiovascular disease risk factors, frailty, neurocognitive and QOL outcomes, social attainment, and subsequent thyroid carcinoma. Associations between serum free thyroxine and thyrotropin levels at assessment and health outcomes were explored. RESULTS: The prevalence of primary hypothyroidism was 14.7% (95% CI, 13.5%-16.0%). It was more likely in females (OR, 1.06; 95% CI, 1.03-1.08), was less likely in non-Whites (OR, 0.96; 95% CI, 0.93-0.99), was associated with thyroid radiotherapy (higher risk at higher doses), and was more common if cancer was diagnosed at an age ≥ 15.0 years versus an age < 5 years (OR, 1.05; 95% CI, 1.01-1.09). Primary hypothyroidism was associated with frailty (OR, 1.54; 95% CI, 1.05-2.26), dyslipidemia (OR, 1.52; 95% CI, 1.14-2.04), impaired physical QOL (OR, 1.66; 95% CI, 1.12-2.48), and having health care insurance (OR, 1.51; 95% CI, 1.07-2.12). CONCLUSIONS: Primary hypothyroidism is common in survivors and is associated with unfavorable physical health and QOL outcomes. The impact of thyroid hormone replacement practices on these outcomes should be investigated further.

Concordance between Self-reported Symptoms and Clinically Ascertained Peripheral Neuropathy among Childhood Cancer Survivors: the St. Jude Lifetime Cohort Study.

BACKGROUND: Childhood cancer survivors are at elevated risk for motor and/or sensory neuropathy. The study aims to evaluate the concordance between self-report peripheral neuropathy compared with clinically ascertained peripheral neuropathy, and to identify factors associated with misclassification of peripheral neuropathy among survivors. METHODS: The concordance between self-report and clinically ascertained peripheral neuropathy was evaluated among 2,933 5+ years old childhood cancer survivors (mean age 33.3, SD = 8.9). The sensitivity, specificity, and accuracy of self-report peripheral motor neuropathy (PMN) and peripheral sensory neuropathy (PSN) were calculated with reference to clinically assessed peripheral neuropathy. RESULTS: Female survivors were more likely than male survivors to have clinically ascertained PMN (8.4% vs. 5.6%, P = 0.004). For females, having either PSN or PMN the most sensitive, specific, and accurate self-reported symptom was endorsing ≥2 symptoms on the self-report questionnaire (43.2%, 90.3%, and 85.2%, respectively), with kappa of 0.304. For males, having either PSN or PMN the most sensitive, specific, and accurate self-reported symptom was endorsing ≥2 symptoms on the self-report questionnaire (38.8%, 90.5%, and 86.3%, respectively) with kappa of 0.242. Age at diagnosis, emotional distress, and reporting pain in legs in the past 4 weeks were associated with an increased risk for false-positive reporting of peripheral neuropathy. Race (White), age at assessment, and emotional distress were associated with increased risk for false-negative reporting of peripheral neuropathy. CONCLUSIONS: Agreement between self-report and clinically ascertained peripheral neuropathy was poor in survivors. Choosing self-report versus clinical ascertained peripheral neuropathy should be carefully considered. IMPACT: The current study identifies the need for a self-report questionnaire that accurately assesses symptoms of peripheral neuropathy among cancer survivors.

Polygenic Risk Score Improves Risk Stratification and Prediction of Subsequent Thyroid Cancer after Childhood Cancer.

BACKGROUND: Subsequent thyroid cancer (STC) is one of the most common malignancies in childhood cancer survivors. We aimed to evaluate the polygenic contributions to STC risk and potential utility in improving risk prediction. METHODS: A polygenic risk score (PRS) was calculated from 12 independent SNPs associated with thyroid cancer risk in the general population. Associations between PRS and STC risk were evaluated among survivors from St. Jude Lifetime Cohort (SJLIFE) and were replicated in survivors from Childhood Cancer Survivor Study (CCSS). A risk prediction model integrating the PRS and clinical factors, initially developed in SJLIFE, and its performance were validated in CCSS. RESULTS: Among 2,370 SJLIFE survivors with a median follow-up of 28.8 [interquartile range (IQR) = 21.9-36.1] years, 65 (2.7%) developed STC. Among them, the standardized PRS was associated with an increased rate of STC [relative rate (RR) = 1.57; 95% confidence interval (CI) = 1.24-1.98; P < 0.001]. Similar associations were replicated in 6,416 CCSS survivors, among whom 121 (1.9%) developed STC during median follow-up of 28.9 (IQR = 22.6-34.6) years (RR = 1.52; 95% CI = 1.25-1.83; P < 0.001). A risk prediction model integrating the PRS with clinical factors showed better performance than the model considering only clinical factors in SJLIFE (P = 0.004, AUC = 83.2% vs. 82.1%, at age 40), which was further validated in CCSS (P = 0.010, AUC = 72.9% vs. 70.6%). CONCLUSIONS: Integration of the PRS with clinical factors provided a statistically significant improvement in risk prediction of STC, although the magnitude of improvement was modest. IMPACT: PRS improves risk stratification and prediction of STC, suggesting its potential utility for optimizing screening strategies in survivorship care.

Persistent variations of blood DNA methylation associated with treatment exposures and risk for cardiometabolic outcomes in long-term survivors of childhood cancer in the St. Jude Lifetime Cohort.

BACKGROUND: It is well-established that cancer treatment substantially increases the risk of long-term adverse health outcomes among childhood cancer survivors. However, there is limited research on the underlying mechanisms. To elucidate the pathophysiology and a possible causal pathway from treatment exposures to cardiometabolic conditions, we conducted epigenome-wide association studies (EWAS) to identify the DNA methylation (DNAm) sites associated with cancer treatment exposures and examined whether treatment-associated DNAm sites mediate associations between specific treatments and cardiometabolic conditions. METHODS: We included 2052 survivors (median age 33.7 years) of European ancestry from the St. Jude Lifetime Cohort Study, a retrospective hospital-based study with prospective clinical follow-up. Cumulative doses of chemotherapy and region-specific radiation were abstracted from medical records. Seven cardiometabolic conditions were clinically assessed. DNAm profile was measured using MethylationEPIC BeadChip with blood-derived DNA. RESULTS: By performing multiple treatment-specific EWAS, we identified 935 5'-cytosine-phosphate-guanine-3' (CpG) sites mapped to 538 genes/regions associated with one or more cancer treatments at the epigenome-wide significance level (p < 9 × 10-8). Among the treatment-associated CpGs, 8 were associated with obesity, 63 with hypercholesterolemia, and 17 with hypertriglyceridemia (false discovery rate-adjusted p < 0.05). We observed substantial mediation by methylation at four independent CpGs (cg06963130, cg21922478, cg22976567, cg07403981) for the association between abdominal field radiotherapy (abdominal-RT) and risk of hypercholesterolemia (70.3%) and by methylation at three CpGs (cg19634849, cg13552692, cg09853238) for the association between abdominal-RT and hypertriglyceridemia (54.6%). In addition, three CpGs (cg26572901, cg12715065, cg21163477) partially mediated the association between brain-RT and obesity with a 32.9% mediation effect, and two CpGs mediated the association between corticosteroids and obesity (cg22351187, 14.2%) and between brain-RT and hypertriglyceridemia (cg13360224, 10.5%). Notably, several mediator CpGs reside in the proximity of well-established dyslipidemia genes: cg21922478 (ITGA1) and cg22976567 (LMNA). CONCLUSIONS: In childhood cancer survivors, cancer treatment exposures are associated with DNAm patterns present decades following the exposure. Treatment-associated DNAm sites may mediate the causal pathway from specific treatment exposures to certain cardiometabolic conditions, suggesting the utility of DNAm sites as risk predictors and potential mechanistic targets for future intervention studies.

The Association of Mitochondrial Copy Number With Sarcopenia in Adult Survivors of Childhood Cancer.

BACKGROUND: Adult childhood cancer survivors are at risk for frailty, including low muscle mass and weakness (sarcopenia). Using peripheral blood mitochondrial DNA copy number (mtDNAcn) as a proxy for functional mitochondria, this study describes cross-sectional associations between mtDNAcn and sarcopenia among survivors. METHODS: Among 1762 adult childhood cancer survivors (51.6% male; median age = 29.4 years, interquartile range [IQR] = 23.3-36.8), with a median of 20.6 years from diagnosis (IQR = 15.2-28.2), mtDNAcn estimates were derived from whole-genome sequencing. A subset was validated by quantitative polymerase chain reaction and evaluated cross-sectionally using multivariable logistic regression for their association with sarcopenia, defined by race-, age-, and sex-specific low lean muscle mass or weak grip strength. All statistical tests were 2-sided. RESULTS: The prevalence of sarcopenia was 27.0%, higher among female than male survivors (31.5% vs 22.9%; P < .001) and associated with age at diagnosis; 51.7% of survivors with sarcopenia were diagnosed ages 4-13 years (P = .01). Sarcopenia was most prevalent (39.0%) among central nervous system tumor survivors. Cranial radiation (odds ratio [OR] = 1.84, 95% confidence interval [CI] = 1.32 to 2.59) and alkylating agents (OR = 1.34, 95% CI = 1.04 to 1.72) increased, whereas glucocorticoids decreased odds (OR = 0.72, 95% CI = 0.56 to 0.93) of sarcopenia. mtDNAcn decreased with age (ß = -0.81, P = .002) and was higher among female survivors (ß = 9.23, P = .01) and among survivors with a C allele at mt.204 (ß = -17.9, P = .02). In adjusted models, every standard deviation decrease in mtDNAcn increased the odds of sarcopenia 20% (OR = 1.20, 95% CI = 1.07 to 1.34). CONCLUSIONS: A growing body of evidence supports peripheral blood mtDNAcn as a biomarker for adverse health outcomes; however, this study is the first to report an association between mtDNAcn and sarcopenia among childhood cancer survivors.