Survival rates for most paediatric cancers have improved at a remarkable pace over the past four decades. In developed countries, cure is now the probable outcome for most children and adolescents ...who are diagnosed with cancer: their 5-year survival rate approaches 80%. However, the vast majority of these cancer survivors will have at least one chronic health condition by 40 years of age. The burden of responsibility to understand the long-term morbidity and mortality that is associated with currently successful treatments must be borne by many, including the research and health care communities, survivor advocacy groups, and governmental and policy-making entities.
•Improvements in childhood cancer survival led to increasing numbers of survivors.•Childhood cancer is treated within multiinstitutional clinical trials.•Chemotherapy is the main element of therapy ...but irradiation is still needed in some.•Survivors are at longstanding risk of severe somatic late effects.•Survivors may face various social and socioeconomic difficulties in adulthood.
Since the 1960s, paediatric oncologists have gradually become better organised in large study groups and participation in clinical trials is today considered as the standard of care, with most children with cancer in Europe and North America being enrolled on available treatment protocols. Chemotherapy is nowadays the main element of therapy, but irradiation is still required for some patients. With the advent of multimodality therapy and supportive care, five-year cancer survival exceeds 80 % in most European and North American countries today. The substantial improvements in survival led to a constantly growing population of childhood cancer survivors. Concerns regarding the risk of late effects of the intensive cancer treatment at a young age, together with increasing numbers of survivors, have directed attention towards survivorship research. Survivors of childhood cancer are at longstanding risk of various severe somatic and mental health conditions attributable to the cancer and its treatment, as well as adverse social and socioeconomic consequences, and diminished psychological well-being and quality of life. It is, however, important to stress that some survivors have no or very mild adverse health conditions. Nevertheless, joint efforts are warranted for the care and long-term follow-up of childhood cancer patients.
With this article, we provide a comprehensive overview of improvements in survival and treatment modalities over time, as well as the related somatic and mental late effects, and social and socioeconomic difficulties that these children might encounter later in life.
Summary Background The effect of many contemporary chemotherapeutic drugs on pregnancy and livebirth is not well established. We aimed to establish the effects of these drugs on pregnancy in male and ...female survivors of childhood cancer not exposed to pelvic or cranial radiotherapy. Methods We used data from a subset of the Childhood Cancer Survivor Study cohort, which followed 5-year survivors of the most common types of childhood cancer who were diagnosed before age 21 years and treated at 27 institutions in the USA and Canada between 1970 and 1999. We extracted doses of 14 alkylating and similar DNA interstrand crosslinking drugs from medical records. We used sex-specific Cox models to establish the independent effects of each drug and the cumulative cyclophosphamide equivalent dose of all drugs in relation to pregnancies and livebirths occurring between ages 15 years and 44 years. We included siblings of survivors as a comparison group. Findings We included 10 938 survivors and 3949 siblings. After a median follow-up of 8 years (IQR 4–12) from cohort entry or at age 15 years, whichever was later, 4149 (38%) survivors reported having or siring a pregnancy, of whom 3453 (83%) individuals reported at least one livebirth. After a median follow-up of 10 years (IQR 6–15), 2445 (62%) siblings reported having or siring a pregnancy, of whom 2201 (90%) individuals reported at least one livebirth. In multivariable analysis, survivors had a decreased likelihood of siring or having a pregnancy versus siblings (male survivors: hazard ratio HR 0·63, 95% CI 0·58–0·68; p<0·0001; female survivors: 0·87, 0·81–0·94; p<0·0001) or of having a livebirth (male survivors: 0·63, 0·58–0·69; p<0·0001; female survivors: 0·82, 0·76–0·89; p<0·0001). In male survivors, reduced likelihood of pregnancy was associated with upper tertile doses of cyclophosphamide (HR 0·60, 95% CI 0·51–0·71; p<0·0001), ifosfamide (0·42, 0·23–0·79; p=0·0069), procarbazine (0·30, 0·20–0·46; p<0·0001) and cisplatin (0·56, 0·39–0·82; p=0·0023). Cyclophosphamide equivalent dose in male survivors was significantly associated with a decreased likelihood of siring a pregnancy (per 5000 mg/m2 increments: HR 0·82, 95% CI 0·79–0·86; p<0·0001). However, in female survivors, only busulfan (<450 mg/m2 HR 0·22, 95% CI 0·06–0·79; p=0·020; ≥450 mg/m2 0·14, 0·03–0·55; p=0·0051) and doses of lomustine equal to or greater than 411 mg/m2 (0·41, 0·17–0·98; p=0·046) were significantly associated with reduced pregnancy; cyclophosphamide equivalent dose was associated with risk only at the highest doses in analyses categorised by quartile (upper quartile vs no exposure: HR 0·85, 95% CI 0·74–0·98; p=0·023). Results for livebirth were similar to those for pregnancy. Interpretation Greater doses of contemporary alkylating drugs and cisplatin were associated with a decreased likelihood of siring a pregnancy in male survivors of childhood cancer. However, our findings should provide reassurance to most female survivors treated with chemotherapy without radiotherapy to the pelvis or brain, given that chemotherapy-specific effects on pregnancy were generally few. Nevertheless, consideration of fertility preservation before cancer treatment remains important to maximise the reproductive potential of all adolescents newly diagnosed with cancer. Funding National Cancer Institute, National Institutes of Health, and the American Lebanese–Syrian Associated Charities.
Summary Background Previous studies have shown decreased pregnancy rates and early menopause in female cancer survivors; however, infertility rates and reproductive interventions have not been ...studied. We investigated infertility and time to pregnancy in female childhood cancer survivors, and analysed treatment characteristics associated with infertility and subsequent pregnancy. Methods The Childhood Cancer Survivor Study (CCSS) is a cohort study including 5 year cancer survivors from 26 Canadian and US institutions who were younger than 21 years at the time of diagnosis between Jan 1, 1970, and Dec 31, 1986, and a sibling control group. We included women aged 18–39 years who had ever been sexually active. We gathered demographic, medical, and reproductive data via a baseline questionnaire, and quantified exposure to alkylating agents and radiation therapy. Self-reported infertility, medical treatment for infertility, time to first pregnancy in survivors and siblings, and the risk of infertility in survivors by demographic, disease, and treatment variables were analysed. Findings 3531 survivors and 1366 female sibling controls who enrolled between Nov 3, 1992, and April 4, 2004, were included. Compared with their siblings, survivors had an increased risk (relative risk RR 1·48 95% CI 1·23–1·78; p<0·0001) of clinical infertility (ie, >1 year of attempts at conception without success), which was most pronounced at early reproductive ages (RR 2·92 95% CI 1·18–7·20, p=0·020, in participants ≤24 years; 1·61 1·05–2·48, p=0·029, in those aged 25–29 years; and 1·37 1·11–1·69, p=0·0035, in those aged 30–40 years). Despite being equally likely to seek treatment for infertility, survivors were less likely than were their siblings to be prescribed drugs for treatment of infertility (0·57 95% CI 0·46–0·70, p<0·0001). Increasing doses of uterine radiation and alkylating agent chemotherapy were strongly associated with infertility. Although survivors had an increased time to pregnancy compared with their siblings (p=0·032), 292 (64%) of 455 participants with self-reported clinical infertility achieved a pregnancy. Interpretation A more comprehensive understanding of infertility after cancer is crucial for counselling and decision making about future conception attempts and fertility preservation. Funding National Cancer Institute, American Lebanese Syrian Associated Charities, Swim Across America.
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.
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.
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.
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.
National Cancer Institute and American Lebanese-Syrian Associated Charities.
The first generation of childhood cancer survivors is now aging into their fourth and fifth decades of life, yet health risks across the aging spectrum are not well established.
Analyses included ...14,359 5-year survivors from the Childhood Cancer Survivor Study, who were first diagnosed when they were younger than 21 years old and who received follow-up for a median of 24.5 years after diagnosis (range, 5.0 to 39.3 years) along with 4,301 of their siblings. Among the survivors, 5,604 were at least 35 years old (range, 35 to 62 years) at last follow-up. Severe, disabling, life-threatening, and fatal health conditions more than 5 years from diagnosis were classified using the Common Terminology Criteria for Adverse Events, grades 3 to 5 (National Cancer Institute).
The cumulative incidence of a severe, disabling, life-threatening, or fatal health condition was greater among survivors than siblings (53.6%; 95% CI, 51.5 to 55.6; v 19.8%; 95% CI, 17.0 to 22.7) by age 50 years. When comparing survivors with siblings, hazard ratios (HR) were significantly increased within the age group of 5 to 19 years (HR, 6.8; 95% CI, 5.5 to 8.3), age group of 20 to 34 years (HR, 3.8; 95% CI, 3.2 to 4.5), and the ≥ 35 years group (HR, 5.0; 95% CI, 4.1 to 6.1), with the HR significantly higher among those ≥ 35 years versus those 20 to 34 years old (P = .03). Among survivors who reached age 35 years without a previous grade 3 or 4 condition, 25.9% experienced a subsequent grade 3 to 5 condition within 10 years, compared with 6.0% of siblings (P < .001).
Elevated risk for morbidity and mortality among survivors increases further beyond the fourth decade of life, which affects the future clinical demands of this population relative to ongoing surveillance and interventions.
Sequencing errors are key confounding factors for detecting low-frequency genetic variants that are important for cancer molecular diagnosis, treatment, and surveillance using deep next-generation ...sequencing (NGS). However, there is a lack of comprehensive understanding of errors introduced at various steps of a conventional NGS workflow, such as sample handling, library preparation, PCR enrichment, and sequencing. In this study, we use current NGS technology to systematically investigate these questions.
By evaluating read-specific error distributions, we discover that the substitution error rate can be computationally suppressed to 10
to 10
, which is 10- to 100-fold lower than generally considered achievable (10
) in the current literature. We then quantify substitution errors attributable to sample handling, library preparation, enrichment PCR, and sequencing by using multiple deep sequencing datasets. We find that error rates differ by nucleotide substitution types, ranging from 10
for A>C/T>G, C>A/G>T, and C>G/G>C changes to 10
for A>G/T>C changes. Furthermore, C>T/G>A errors exhibit strong sequence context dependency, sample-specific effects dominate elevated C>A/G>T errors, and target-enrichment PCR led to ~ 6-fold increase of overall error rate. We also find that more than 70% of hotspot variants can be detected at 0.1 ~ 0.01% frequency with the current NGS technology by applying in silico error suppression.
We present the first comprehensive analysis of sequencing error sources in conventional NGS workflows. The error profiles revealed by our study highlight new directions for further improving NGS analysis accuracy both experimentally and computationally, ultimately enhancing the precision of deep sequencing.
Among patients in whom childhood cancer was diagnosed in the 1970s and 1980s, 18% of those who survived for 5 years died within the subsequent 25 years. In recent decades, cancer treatments have been ...modified with the goal of reducing life-threatening late effects.
We evaluated late mortality among 34,033 patients in the Childhood Cancer Survivor Study cohort who survived at least 5 years after childhood cancer (i.e., cancer diagnosed before the age of 21 years) for which treatment was initiated during the period from 1970 through 1999. The median follow-up was 21 years (range, 5 to 38). We evaluated demographic and disease factors that were associated with death from health-related causes (i.e., conditions that exclude recurrence or progression of the original cancer and external causes but include the late effects of cancer therapy) using cumulative incidence and piecewise exponential models to estimate relative rates and 95% confidence intervals.
Of the 3958 deaths that occurred during the study period, 1618 (41%) were attributable to health-related causes, including 746 deaths from subsequent neoplasms, 241 from cardiac causes, 137 from pulmonary causes, and 494 from other causes. A reduction in 15-year mortality was observed for death from any cause (from 12.4% in the early 1970s to 6.0% in the 1990s, P<0.001 for trend) and from health-related causes (from 3.5% to 2.1%, P<0.001 for trend). These reductions were attributable to decreases in the rates of death from subsequent neoplasm (P<0.001), cardiac causes (P<0.001), and pulmonary causes (P=0.04). Changes in therapy according to decade included reduced rates of cranial radiotherapy for acute lymphoblastic leukemia (85% in the 1970s, 51% in the 1980s, and 19% in the 1990s), of abdominal radiotherapy for Wilms' tumor (78%, 53%, and 43%, respectively), of chest radiotherapy for Hodgkin's lymphoma (87%, 79%, and 61%, respectively), and of anthracycline exposure. Reduction in treatment exposure was associated with reduced late mortality among survivors of acute lymphoblastic leukemia and Wilms' tumor.
The strategy of lowering therapeutic exposure has contributed to an observed decline in late mortality among 5-year survivors of childhood cancer. (Funded by the National Cancer Institute and the American Lebanese-Syrian Associated Charities.).
Abstract Background Treatment-related cardiac death is the primary, noncancer cause of mortality in adult survivors of childhood malignancies. Early detection of cardiac dysfunction may identify a ...high-risk subset of survivors for early intervention. Objectives This study sought to determine the prevalence of cardiac dysfunction in adult survivors of childhood malignancies. Methods Echocardiographic assessment included 3-dimensional (3D) left ventricular ejection fraction (LVEF), global longitudinal and circumferential myocardial strain, and diastolic function, graded per American Society of Echocardiography guidelines in 1,820 adult (median age 31 years; range: 18 to 65 years) survivors of childhood cancer (median time from diagnosis 23 years; range: 10 to 48 years) exposed to anthracycline chemotherapy (n = 1,050), chest-directed radiotherapy (n = 306), or both (n = 464). Results Only 5.8% of survivors had abnormal 3D LVEFs (<50%). However, 32.1% of survivors with normal 3D LVEFs had evidence of cardiac dysfunction by global longitudinal strain (28%), American Society of Echocardiography–graded diastolic assessment (8.7%), or both. Abnormal global longitudinal strain was associated with chest-directed radiotherapy at 1 to 19.9 Gy (rate ratio RR: 1.38; 95% confidence interval CI: 1.14 to 1.66), 20 to 29.9 Gy (RR: 1.65; 95% CI: 1.31 to 2.08), and >30 Gy (RR: 2.39; 95% CI: 1.79 to 3.18) and anthracycline dose > 300 mg/m2 (RR: 1.72; 95% CI: 1.31 to 2.26). Survivors with metabolic syndrome were twice as likely to have abnormal global longitudinal strain (RR: 1.94; 95% CI: 1.66 to 2.28) and abnormal diastolic function (RR: 1.68; 95% CI: 1.39 to 2.03) but not abnormal 3D LVEFs (RR: 1.07; 95% CI: 0.74 to 1.53). Conclusions Abnormal global longitudinal strain and diastolic function are more prevalent than reduced 3D LVEF and are associated with treatment exposure. They may identify a subset of survivors at higher risk for poor clinical cardiac outcomes who may benefit from early medical intervention.
Summary Acute lymphoblastic leukaemia, a malignant disorder of lymphoid progenitor cells, affects both children and adults, with peak prevalence between the ages of 2 and 5 years. Steady progress in ...development of effective treatments has led to a cure rate of more than 80% in children, creating opportunities for innovative approaches that would preserve past gains in leukaemia-free survival while reducing the toxic side-effects of current intensive regimens. Advances in our understanding of the pathobiology of acute lymphoblastic leukaemia, fuelled by emerging molecular technologies, suggest that drugs specifically targeting the genetic defects of leukaemic cells could revolutionise management of this disease. Meanwhile, studies are underway to ascertain the precise events that take place in the genesis of acute lymphoblastic leukaemia, to enhance the clinical application of known risk factors and antileukaemic agents, and to identify treatment regimens that might boost the generally low cure rates in adults and subgroups of children with high-risk leukaemia.
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