Cumulative Absolute Risk of Subsequent Colorectal Cancer After Abdominopelvic Radiotherapy Among Childhood Cancer Survivors: A PanCareSurFup Study.

PURPOSE: Childhood cancer survivors are at the risk of developing subsequent colorectal cancers (CRCs), but the absolute risks by treatment modality are uncertain. We quantified the absolute risks by radiotherapy treatment characteristics using clinically accessible data from a Pan-European wide case-control study nested within a large cohort of childhood cancer survivors: the PanCareSurFup Study. METHODS: Odds ratios (ORs) from a case-control study comprising 143 CRC cases and 143 controls nested within a cohort of 69,460 survivors were calculated. These, together with standardized incidence ratios for CRC for this cohort and European general population CRC incidence rates and survivors' mortality rates, were used to estimate cumulative absolute risks (CARs) by attained age for different categories of radiation to the abdominopelvic area. RESULTS: Overall, survivors treated with abdominopelvic radiotherapy treatment (ART) were three times more likely to develop a subsequent CRC than those who did not receive ART (OR, 3.1 [95% CI, 1.4 to 6.6]). For male survivors treated with ART, the CAR was 0.27% (95% CI, 0.17 to 0.59) by age 40 years, 1.08% (95% CI, 0.69 to 2.34) by age 50 years (0.27% expected in the general population), and 3.7% (95% CI, 2.36 to 7.80) by age 60 years (0.95% expected). For female survivors treated with ART, the CAR was 0.29% (95% CI, 0.18 to 0.62) by age 40 years, 1.03% (95% CI, 0.65 to 2.22) by age 50 years (0.27% expected), and 3.0% (95% CI, 1.91 to 6.37) by age 60 years (0.82% expected). CONCLUSION: We demonstrated that by age 40 years survivors of childhood cancer treated with ART already have a similar risk of CRC as those age 50 years in the general population for whom population-based CRC screening begins in many countries. This information should be used in the development of survivorship guidelines for the risk stratification of survivors concerning CRC risk.

Risk Factors for Primary Bone Cancer After Childhood Cancer: A PanCare Childhood and Adolescent Cancer Survivor Care and Follow-Up Studies Nested Case-Control Study.

PURPOSE: Radiation to the bone and exposure to alkylating agents increases the risk of bone cancer among survivors of childhood cancer, but there is uncertainty regarding the risks of bone tissue radiation doses below 10 Gy and the dose-response relationship for specific types of chemotherapy. METHODS: Twelve European countries contributed 228 cases and 228 matched controls to a nested case-control study within a cohort of 69,460 5-year survivors of childhood cancer. Odds ratios (ORs) of developing bone cancer for different levels of cumulative radiation exposure and cumulative doses of specific types of chemotherapy were calculated. Excess ORs were calculated to investigate the shape and extent of any dose-response relationship. RESULTS: The OR associated with bone tissue exposed to 1-4 Gy was 4.8-fold (95% CI, 1.2 to 19.6) and to 5-9 Gy was 9.6-fold (95% CI, 2.4 to 37.4) compared with unexposed bone tissue. The OR increased linearly with increasing dose of radiation (Ptrend < .001) up to 78-fold (95% CI, 9.2 to 669.9) for doses of ≥40 Gy. For cumulative alkylating agent doses of 10,000-19,999 and ≥20,000 mg/m2, the radiation-adjusted ORs were 7.1 (95% CI, 2.2 to 22.8) and 8.3 (95% CI, 2.8 to 24.4), respectively, with independent contributions from each of procarbazine, ifosfamide, and cyclophosphamide. Other cytotoxics were not associated with bone cancer. CONCLUSION: To our knowledge, we demonstrate-for the first time-that the risk of bone cancer is increased 5- to 10-fold after exposure of bone tissue to cumulative radiation doses of 1-9 Gy. Alkylating agents exceeding 10,000 mg/m2 increase the risk 7- to 8-fold, particularly following procarbazine, ifosfamide, and cyclophosphamide. These substantially elevated risks should be used to develop/update clinical follow-up guidelines and survivorship care plans.

Risk of subsequent primary oral cancer in a cohort of 69,460 5-year survivors of childhood and adolescent cancer in Europe: the PanCareSurFup study.

BACKGROUND: Survivors of childhood cancer are at risk of subsequent primary malignant neoplasms (SPNs), but the risk for rarer types of SPNs, such as oral cancer, is uncertain. Previous studies included few oral SPNs, hence large-scale cohorts are required to identify groups at risks. METHODS: The PanCareSurFup cohort includes 69,460 5-year survivors of childhood cancer across Europe. Risks of oral SPNs were defined by standardised incidence ratios (SIRs), absolute excess risks and cumulative incidence. RESULTS: One hundred and forty-five oral SPNs (64 salivary gland, 38 tongue, 20 pharynx, 2 lip, and 21 other) were ascertained among 143 survivors. Survivors were at 5-fold risk of an oral SPN (95% CI: 4.4-5.6). Survivors of leukaemia were at greatest risk (SIR = 19.2; 95% CI: 14.6-25.2) followed by bone sarcoma (SIR = 6.4, 95% CI: 3.7-11.0), Hodgkin lymphoma (SIR = 6.2, 95% CI: 3.9-9.9) and soft-tissue sarcoma (SIR = 5.0, 95% CI: 3.0-8.5). Survivors treated with radiotherapy were at 33-fold risk of salivary gland SPNs (95% CI: 25.3-44.5), particularly Hodgkin lymphoma (SIR = 66.2, 95% CI: 43.6-100.5) and leukaemia (SIR = 50.5, 95% CI: 36.1-70.7) survivors. Survivors treated with chemotherapy had a substantially increased risk of a tongue SPN (SIR = 15.9, 95% CI: 10.6-23.7). CONCLUSIONS: Previous radiotherapy increases the risk of salivary gland SPNs considerably, while chemotherapy increases the risk of tongue SPNs substantially. Awareness of these risks among both health-care professionals and survivors could play a crucial role in detecting oral SPNs early.

Risk of subsequent primary lymphoma in a cohort of 69,460 five-year survivors of childhood and adolescent cancer in Europe: The PanCareSurFup study.

BACKGROUND: Survivors of Hodgkin lymphoma (HL) are at risk of developing non-Hodgkin lymphoma (NHL) after treatment; however, the risks of developing subsequent primary lymphomas (SPLs), including HL and NHL, after different types of childhood cancer are unknown. The authors quantified the risk of SPLs using the largest cohort of childhood cancer survivors worldwide. METHODS: The Pan-European Network for Care of Survivors After Childhood and Adolescent Cancer (PanCare) Survivor Care and Follow-Up Studies (PanCareSurFup) cohort includes 69,460 five-year survivors of childhood cancer, diagnosed during 1940 through 2008, from 12 European countries. Risks of SPLs were quantified by standardized incidence ratios (SIRs) and relative risks (RRs) using multivariable Poisson regression. RESULTS: Overall, 140 SPLs, including 104 NHLs and 36 HLs, were identified. Survivors were at 60% increased risk of an SPL compared with the general population (SIR, 1.6; 95% confidence interval [CI], 1.4-1.9). Survivors were twice as likely to develop NHL (SIR, 2.3; 95% CI, 1.9-2.8), with the greatest risks among survivors of HL (SIR, 7.1; 95% CI, 5.1-10.0), Wilms tumor (SIR, 3.1; 95% CI, 1.7-5.7), leukemia (SIR, 2.8; 95% CI, 1.8-4.4), and bone sarcoma (SIR, 2.7; 95% CI, 1.4-5.4). Treatment with chemotherapy for any cancer doubled the RR of NHL (RR, 2.1; 95% CI, 1.2-3.9), but treatment with radiotherapy did not (RR, 1.2; 95% CI, 0.7-2.0). Survivors were at similar risk of developing a subsequent HL as the general population (SIR, 1.1; 95% CI, 0.8-1.5). CONCLUSIONS: In addition to HL, the authors show here for the first time that survivors of Wilms tumor, leukemia, and bone sarcoma are at risk of NHL. Survivors and health care professionals should be aware of the risk of NHL in these survivors and in any survivors treated with chemotherapy.

Impact of era of diagnosis on cause-specific late mortality among 77 423 five-year European survivors of childhood and adolescent cancer: The PanCareSurFup consortium.

Late mortality of European 5-year survivors of childhood or adolescent cancer has dropped over the last 60 years, but excess mortality persists. There is little information concerning secular trends in cause-specific mortality among older European survivors. PanCareSurFup pooled data from 12 cancer registries and clinics in 11 European countries from 77 423 five-year survivors of cancer diagnosed before age 21 between 1940 and 2008 followed for an average age of 21 years and a total of 1.27 million person-years to determine their risk of death using cumulative mortality, standardized mortality ratios (SMR), absolute excess risks (AER), and multivariable proportional hazards regression analyses. At the end of follow-up 9166 survivors (11.8%) had died compared to 927 expected (SMR 9.89, 95% confidence interval [95% CI] 9.69-10.09), AER 6.47 per 1000 person-years, (95% CI 6.32-6.62). At 60 to 68 years of attained age all-cause mortality was still higher than expected (SMR = 2.41, 95% CI 1.90-3.02). Overall cumulative mortality at 25 years from diagnosis dropped from 18.4% (95% CI 16.5-20.4) to 7.3% (95% CI 6.7-8.0) over the observation period. Compared to the diagnosis period 1960 to 1969, the mortality hazard ratio declined for first neoplasms (P for trend <.0001) and for infections (P < .0001); declines in relative mortality from second neoplasms and cardiovascular causes were less pronounced (P = .1105 and P = .0829, respectively). PanCareSurFup is the largest study with the longest follow-up of late mortality among European childhood and adolescent cancer 5-year survivors, and documents significant mortality declines among European survivors into modern eras. However, continuing excess mortality highlights survivors' long-term care needs.

Risk of digestive cancers in a cohort of 69 460 five-year survivors of childhood cancer in Europe: the PanCareSurFup study.

BACKGROUND: Survivors of childhood cancer are at risk of subsequent primary neoplasms (SPNs), but the risk of developing specific digestive SPNs beyond age 40 years remains uncertain. We investigated risks of specific digestive SPNs within the largest available cohort worldwide. METHODS: The PanCareSurFup cohort includes 69 460 five-year survivors of childhood cancer from 12 countries in Europe. Risks of digestive SPNs were quantified using standardised incidence ratios (SIRs), absolute excess risks and cumulative incidence. RESULTS: 427 digestive SPNs (214 colorectal, 62 liver, 48 stomach, 44 pancreas, 59 other) were diagnosed in 413 survivors. Wilms tumour (WT) and Hodgkin lymphoma (HL) survivors were at greatest risk (SIR 12.1; 95% CI 9.6 to 15.1; SIR 7.3; 95% CI 5.9 to 9.0, respectively). The cumulative incidence increased the most steeply with increasing age for WT survivors, reaching 7.4% by age 55% and 9.6% by age 60 years (1.0% expected based on general population rates). Regarding colorectal SPNs, WT and HL survivors were at greatest risk; both seven times that expected. By age 55 years, 2.3% of both WT (95% CI 1.4 to 3.9) and HL (95% CI 1.6 to 3.2) survivors had developed a colorectal SPN-comparable to the risk among members of the general population with at least two first-degree relatives affected. CONCLUSIONS: Colonoscopy surveillance before age 55 is recommended in many European countries for individuals with a family history of colorectal cancer, but not for WT and HL survivors despite a comparable risk profile. Clinically, serious consideration should be given to the implementation of colonoscopy surveillance while further evaluation of its benefits, harms and cost-effectiveness in WT and HL survivors is undertaken.

Risk of subsequent primary leukaemias among 69,460 five-year survivors of childhood cancer diagnosed from 1940 to 2008 in Europe: A cohort study within PanCareSurFup.

BACKGROUND: Survivors of childhood cancers are at risk of developing subsequent primary leukaemias (SPLs), but the long-term risks beyond 20 years of treatment are still unclear. We investigated the risk of SPLs in five-year childhood cancer survivors using a large-scale pan-European (PanCareSurFup) cohort and evaluated variations in the risk by cancer and demographic factors. METHODS: This largest-ever assembled cohort comprises 69,460 five-year childhood cancer survivors from 12 European countries. Standardised incidence ratios (SIRs) and absolute excess risks (AERs) were calculated. RESULTS: One hundred fifteen survivors developed an SPL including 86 myeloid leukaemias (subsequent primary myeloid leukaemias [SPMLs]), 17 lymphoid leukaemias and 12 other types of leukaemias; of these SPLs, 31 (27%) occurred beyond 20 years from the first childhood cancer diagnosis. Compared with the general population, childhood cancer survivors had a fourfold increased risk (SIR = 3.7, 95% confidence interval [CI]: 3.1 to 4.5) of developing leukaemia, and eight leukaemias per 100,000 person-years (AER = 7.5, 95% CI: 6.0 to 9.2) occurred in excess of that expected. The risks remained significantly elevated beyond 20 years from the first primary malignancy (SIR = 2.4, 95% CI: 1.6 to 3.4). Overall, the risk ratio for SPML (SIR = 5.8, 95% CI: 4.6 to 7.1) was higher than that for other SPLs. CONCLUSIONS: We demonstrate that beyond 20 years after childhood cancer diagnosis, survivors experience an increased risk for SPLs compared with that expected from the general population. Our findings highlight the need for awareness by survivors and their healthcare providers for potential risk related to SPL.

Disease-specific Hospitalizations Among 5-Year Survivors of Hepatoblastoma: A Nordic Population-based Cohort Study.

INTRODUCTION: The long-term risk of somatic disease in hepatoblastoma survivors has not been thoroughly evaluated in previous studies. In this population-based study of 86 five-year HB survivors, we used inpatient registers to evaluate the risk for a range of somatic diseases. METHODS: In total, 86 five-year survivors of hepatoblastoma were identified in the Nordic cancer registries from 1964 to 2008 and 152,231 population comparisons were selected. Study subjects were followed in national hospital registries for somatic disease classified into 12 main diagnostic groups. Standardized hospitalization rate ratios (RRs) and absolute excess risks were calculated. RESULTS: After a median follow-up of 11 years, 35 of the 86 five-year hepatoblastoma survivors had been hospitalized with a total of 69 hospitalizations, resulting in an RR of 2.7 (95% confidence interval [CI], 2.2-3.5) and an overall absolute excess risk of 4.2 per 100 person-years. Highest risk was seen for benign neoplasms (RR=16) with 6 hospitalizations for benign neoplasms in the colon and one in rectum. CONCLUSIONS: The pattern of hospitalizations found in this first comprehensive follow-up of hepatoblastoma survivors seems reassuring. Less than 50% of the 5-year survivors had been hospitalized and often for diseases that were not severe or life-threatening.

Risk of cardiovascular disease among Nordic childhood cancer survivors with diabetes mellitus: A report from adult life after childhood cancer in Scandinavia.

BACKGROUND: Childhood cancer survivors have an increased risk of cardiovascular disease (CVD) and diabetes mellitus. Because diabetes is a potentially modifiable risk factor for CVD in the general population, it is important to understand how diabetes affects the risk of CVD among childhood cancer survivors. METHODS: This study examined the risk of CVD among survivors with diabetes and 142,742 population comparison subjects. From the national cancer registries of the 5 Nordic countries, 29,324 one-year survivors of cancer diagnosed before the age of 20 years between 1968 and 2008 were identified. Study subjects were linked to the national hospital registers. The cumulative incidence of CVD was determined with competing risk methods. A Cox proportional hazards model was used to estimate the effects of diabetes and cancer on the hazard of CVD. The interaction between diabetes and cancer was analyzed. RESULTS: Diabetes was diagnosed in 324 of the 29,324 one-year survivors, and CVD was diagnosed in 2108. The hazard of diabetes was 1.7 times higher among survivors than comparison subjects (hazard ratio [HR], 1.7; 95% confidence interval [CI], 1.5-1.9), whereas the HR of CVD was 3.6 (95% CI, 3.3-3.8) 1 to 15 years after the cancer diagnosis and 1.9 (95% CI, 1.8-2.0) after more than 15 years. Individuals with diabetes had a 2.4 times higher hazard of CVD (95% CI, 2.1-2.8) among both survivors and comparison subjects in comparison with individuals without diabetes. CONCLUSIONS: Childhood cancer survivors with diabetes have a markedly increased risk of CVD in comparison with survivors without diabetes. However, diabetes does not increase the risk of CVD more in survivors than the general population.

The PanCareSurFup consortium: research and guidelines to improve lives for survivors of childhood cancer.

BACKGROUND: Second malignant neoplasms and cardiotoxicity are among the most serious and frequent adverse health outcomes experienced by childhood and adolescent cancer survivors (CCSs) and contribute significantly to their increased risk of premature mortality. Owing to differences in health-care systems, language and culture across the continent, Europe has had limited success in establishing multi-country collaborations needed to assemble the numbers of survivors required to clarify the health issues arising after successful cancer treatment. PanCareSurFup (PCSF) is the first pan-European project to evaluate some of the serious long-term health risks faced by survivors. This article sets out the overall rationale, methods and preliminary results of PCSF. METHODS: The PCSF consortium pooled data from 13 cancer registries and hospitals in 12 European countries to evaluate subsequent primary malignancies, cardiac disease and late mortality in survivors diagnosed between ages 0 and 20 years. In addition, PCSF integrated radiation dosimetry to sites of second malignancies and to the heart, developed evidence-based guidelines for long-term care and for transition services, and disseminated results to survivors and the public. RESULTS: We identified 115,596 individuals diagnosed with cancer, of whom 83,333 were 5-year survivors and diagnosed from 1940 to 2011. This single data set forms the basis for cohort analyses of subsequent malignancies, cardiac disease and late mortality and case-control studies of subsequent malignancies and cardiac disease in 5-year survivors. CONCLUSIONS: PCSF delivered specific estimates of risk and comprehensive guidelines to help survivors and care-givers. The expected benefit is to provide every European CCS with improved access to care and better long-term health.

Risk of Subsequent Bone Cancers Among 69 460 Five-Year Survivors of Childhood and Adolescent Cancer in Europe.

Introduction: We investigate the risks of subsequent primary bone cancers after childhood and adolescent cancer in 12 European countries. For the first time, we satisfactorily address the risks beyond 40 years from diagnosis and beyond 40 years of age among all survivors. Methods: This largest-ever assembled cohort comprises 69 460 five-year survivors of cancer diagnosed before age 20 years. Standardized incidence ratios, absolute excess risks, and multivariable-adjusted relative risks and relative excess risks were calculated. All statistical tests were two-sided. Results: Overall, survivors were 21.65 times (95% confidence interval = 18.97 to 24.60 times) more likely to be diagnosed with a subsequent primary bone cancer than expected from the general population. The greatest excess numbers of bone cancers were observed after retinoblastoma, bone sarcoma, and soft tissue sarcoma. The excess number of bone cancers declined linearly with both years since diagnosis and attained age (all P < .05). Beyond 40 years from diagnosis and age 40 years, there were at most 0.45 excess bone cancers among all survivors per 10 000 person-years at risk; beyond 30 years from diagnosis and age 30 years, there were at most 5.02 excess bone cancers after each of retinoblastoma, bone sarcoma, and soft tissue sarcoma, per 10 000 person-years at risk. Conclusions: For all survivors combined and the cancer groups with the greatest excess number of bone cancers, the excess numbers observed declined with both age and years from diagnosis. These results provide novel, reliable, and unbiased information about risks and risk factors among long-term survivors of childhood and adolescent cancer.

Risk of Soft-Tissue Sarcoma Among 69 460 Five-Year Survivors of Childhood Cancer in Europe.

Background: Childhood cancer survivors are at risk of subsequent primary soft-tissue sarcomas (STS), but the risks of specific STS histological subtypes are unknown. We quantified the risk of STS histological subtypes after specific types of childhood cancer. Methods: We pooled data from 13 European cohorts, yielding a cohort of 69 460 five-year survivors of childhood cancer. Standardized incidence ratios (SIRs) and absolute excess risks (AERs) were calculated. Results: Overall, 301 STS developed compared with 19 expected (SIR = 15.7, 95% confidence interval [CI] = 14.0 to 17.6). The highest standardized incidence ratios were for malignant peripheral nerve sheath tumors (MPNST; SIR = 40.6, 95% CI = 29.6 to 54.3), leiomyosarcomas (SIR = 29.9, 95% CI = 23.7 to 37.2), and fibromatous neoplasms (SIR = 12.3, 95% CI = 9.3 to 16.0). SIRs for MPNST were highest following central nervous system tumors (SIR = 80.5, 95% CI = 48.4 to 125.7), Hodgkin lymphoma (SIR = 81.3, 95% CI = 35.1 to 160.1), and Wilms tumor (SIR = 76.0, 95% CI = 27.9 to 165.4). Standardized incidence ratios for leiomyosarcoma were highest following retinoblastoma (SIR = 342.9, 95% CI = 245.0 to 466.9) and Wilms tumor (SIR = 74.2, 95% CI = 37.1 to 132.8). AERs for all STS subtypes were generally low at all years from diagnosis (AER < 1 per 10 000 person-years), except for leiomyosarcoma following retinoblastoma, for which the AER reached 52.7 (95% CI = 20.0 to 85.5) per 10 000 person-years among patients who had survived at least 45 years from diagnosis of retinoblastoma. Conclusions: For the first time, we provide risk estimates of specific STS subtypes following childhood cancers and give evidence that risks of MPNSTs, leiomyosarcomas, and fibromatous neoplasms are particularly increased. While the multiplicative excess risks relative to the general population are substantial, the absolute excess risk of developing any STS subtype is low, except for leiomyosarcoma after retinoblastoma. These results are likely to be informative for both survivors and health care providers.

Liver diseases in Adult Life after Childhood Cancer in Scandinavia (ALiCCS): A population-based cohort study of 32,839 one-year survivors.

Information on late onset liver complications after childhood cancer is scarce. To ensure an appropriate follow-up of childhood cancer survivors and reducing late liver complications, the need for comprehensive and accurate information is presented. We evaluate the risk of liver diseases in a large childhood cancer survivor cohort. We included all 1-year survivors of childhood cancer treated in the five Nordic countries. A Cox proportional hazards model was used to estimate hospitalisation rate (hazard) ratios (HRs) for each liver outcome according to type of cancer. We used the risk among survivors of central nervous system tumour as internal reference. With a median follow-up time of 10 years, 659 (2%) survivors had been hospitalised at least once for a liver disease. The risk for hospitalisation for any liver disease was high after hepatic tumour (HR = 6.9) and leukaemia (HR = 1.7). The Danish sub-cohort of leukaemia treated with haematopoietic stem cell transplantation had a substantially higher risk for hospitalisation for all liver diseases combined (HR = 3.8). Viral hepatitis accounted for 286 of 659 hospitalisations corresponding to 43% of all survivors hospitalised for liver disease. The 20-year cumulative risk of viral hepatitis was 1.8% for survivors diagnosed with cancer before 1990 but only 0.3% for those diagnosed after 1990. The risk of liver disease was low but significantly increased among survivors of hepatic tumours and leukaemia. Further studies with focus on the different treatment modalities are needed to further strengthen the prevention of treatment-induced late liver complications.

Measuring childhood cancer late effects: evidence of a healthy survivor effect.

INTRODUCTION: Given considerable focus on health outcomes among childhood cancer survivors, we aimed to explore whether survivor bias is apparent during long-term follow-up of childhood cancer survivors. METHODS: We identified all 1-year survivors of cancer diagnosed before 20 years of age in Denmark, Finland, Iceland, and Sweden. From the general population, we randomly sampled a comparison cohort. Study individuals were followed for hospitalizations for diseases of the gastroenterological tract, endocrine system, cardiovascular system, or urinary tract from the start of the cancer registries to 2010. We estimated cumulative incidence with death as competing risk and used threshold regression to compare the hazards of the diseases of interest at ages 20, 40, 60, and 75 years. RESULTS: Our study included 27,007 one-year survivors of childhood cancer and 165,620 individuals from the general population. The cumulative incidence of all four outcomes was higher for childhood cancer survivors during early adulthood, but for three outcomes, the cumulative incidence was higher for the general population after age 55 years. The hazard ratios (HRs) decreased for all outcomes with increasing age, and for two of the outcomes, the hazards were higher for the general population at older ages (endocrine diseases: age-specific HRs = 3.0, 1.4, 1.0, 0.87; Cardiovascular diseases: age-specific HRs = 4.1, 1.4, 0.97, 0.84). CONCLUSIONS: Our findings provide empirical evidence that survivor bias attenuates measures of association when comparing survivors with the general population. The design and analysis of studies among childhood cancer survivors, particularly as this population attains older ages, should account for survivor bias to avoid misinterpreting estimates of disease burden.

Long-term inpatient disease burden in the Adult Life after Childhood Cancer in Scandinavia (ALiCCS) study: A cohort study of 21,297 childhood cancer survivors.

BACKGROUND: Survivors of childhood cancer are at increased risk for a wide range of late effects. However, no large population-based studies have included the whole range of somatic diagnoses including subgroup diagnoses and all main types of childhood cancers. Therefore, we aimed to provide the most detailed overview of the long-term risk of hospitalisation in survivors of childhood cancer. METHODS AND FINDINGS: From the national cancer registers of Denmark, Finland, Iceland, and Sweden, we identified 21,297 5-year survivors of childhood cancer diagnosed with cancer before the age of 20 years in the periods 1943-2008 in Denmark, 1971-2008 in Finland, 1955-2008 in Iceland, and 1958-2008 in Sweden. We randomly selected 152,231 population comparison individuals matched by age, sex, year, and country (or municipality in Sweden) from the national population registers. Using a cohort design, study participants were followed in the national hospital registers in Denmark, 1977-2010; Finland, 1975-2012; Iceland, 1999-2008; and Sweden, 1968-2009. Disease-specific hospitalisation rates in survivors and comparison individuals were used to calculate survivors' standardised hospitalisation rate ratios (RRs), absolute excess risks (AERs), and standardised bed day ratios (SBDRs) based on length of stay in hospital. We adjusted for sex, age, and year by indirect standardisation. During 336,554 person-years of follow-up (mean: 16 years; range: 0-42 years), childhood cancer survivors experienced 21,325 first hospitalisations for diseases in one or more of 120 disease categories (cancer recurrence not included), when 10,999 were expected, yielding an overall RR of 1.94 (95% confidence interval [95% CI] 1.91-1.97). The AER was 3,068 (2,980-3,156) per 100,000 person-years, meaning that for each additional year of follow-up, an average of 3 of 100 survivors were hospitalised for a new excess disease beyond the background rates. Approximately 50% of the excess hospitalisations were for diseases of the nervous system (19.1% of all excess hospitalisations), endocrine system (11.1%), digestive organs (10.5%), and respiratory system (10.0%). Survivors of all types of childhood cancer were at increased, persistent risk for subsequent hospitalisation, the highest risks being those of survivors of neuroblastoma (RR: 2.6 [2.4-2.8]; n = 876), hepatic tumours (RR: 2.5 [2.0-3.1]; n = 92), central nervous system tumours (RR: 2.4 [2.3-2.5]; n = 6,175), and Hodgkin lymphoma (RR: 2.4 [2.3-2.5]; n = 2,027). Survivors spent on average five times as many days in hospital as comparison individuals (SBDR: 4.96 [4.94-4.98]; n = 422,218). The analyses of bed days in hospital included new primary cancers and recurrences. Of the total 422,218 days survivors spent in hospital, 47% (197,596 bed days) were for new primary cancers and recurrences. Our study is likely to underestimate the absolute overall disease burden experienced by survivors, as less severe late effects are missed if they are treated sufficiently in the outpatient setting or in the primary health care system. CONCLUSIONS: Childhood cancer survivors were at increased long-term risk for diseases requiring inpatient treatment even decades after their initial cancer. Health care providers who do not work in the area of late effects, especially those in primary health care, should be aware of this highly challenged group of patients in order to avoid or postpone hospitalisations by prevention, early detection, and appropriate treatments.

Being Young and Getting Cancer: Development of a Questionnaire Reflecting the Needs and Experiences of Adolescents and Young Adults with Cancer.

PURPOSE: Cancer is the leading cause of nonaccidental deaths among adolescents and young adults (AYAs). In Denmark, there are substantial gaps in knowledge concerning how AYAs with cancer perceive their diagnostic and therapeutic trajectory and report health-related outcomes. The aim of this study is to describe the development of a questionnaire targeting AYAs with cancer aiming to evaluate treatment and survivorship from the perspective of the patients. METHODS: Identification of themes and development of items included in the questionnaire were based on a synthesis of literature and qualitative interviews with AYAs in an iterative process involving both a professional advisory panel and a youth panel. During the development process, items were validated through cognitive interviews. RESULTS: The final questionnaire contained 151 closed- and open-ended items divided into 6 sections regarding: (1) "Time before treatment," (2) "Being told about your illness," (3) "Being a young patient," (4) "Your treatment," (5) "Receiving help living with and after Cancer," and (6) "How are you feeling today?." One hundred one items were specifically developed for this study, while 50 were standardized validated indexes. The questionnaire combined different types of items such as needs, preferences, experiences, and patient-reported outcomes. CONCLUSION: This is one of few developed questionnaires aiming to evaluate the perspective of AYAs with cancer through their whole cancer trajectory. Results from the questionnaire survey are intended for quality improvements and research in AYA cancer care. The study highlights the importance of an extensive patient involvement in all steps of a questionnaire development process.

Long-term risk of renal and urinary tract diseases in childhood cancer survivors: A population-based cohort study.

BACKGROUND: Childhood cancer has been associated with long-term risk of urinary tract diseases, but risk patterns remain to be comprehensively investigated. We analysed the lifetime risk of urinary tract diseases in survivors of childhood cancer in the Nordic countries. METHODS: We identified 32,519 one-year survivors of childhood cancer diagnosed since the 1940s and 1950s in the five Nordic cancer registries and selected 211,156 population comparisons of a corresponding age, sex, and country of residence from the national population registries. To obtain information on all first-time hospitalizations for a urinary tract disease, we linked all study subjects to the national hospital registry of each country. Relative risks (RRs) and absolute excess risks (AERs) and associated 95% confidence intervals (CIs) for urinary tract diseases among cancer survivors were calculated with the appropriate morbidity rates among comparisons as reference. RESULTS: We observed 1645 childhood cancer survivors ever hospitalized for urinary tract disease yielding an RR of 2.5 (95% CI 2.4-2.7) and an AER of 229 (95% CI 210-248) per 100,000 person-years. The cumulative risk at age 60 was 22% in cancer survivors and 10% in comparisons. Infections of the urinary system and chronic kidney disease showed the highest excess risks, whereas survivors of neuroblastoma, hepatic and renal tumours experienced the highest RRs. CONCLUSION: Survivors of childhood cancer had an excess risk of urinary tract diseases and for most diseases the risk remained elevated throughout life. The highest risks occurred following therapy of childhood abdominal tumours.

Gastrointestinal and liver disease in Adult Life After Childhood Cancer in Scandinavia: A population-based cohort study.

Survival after childhood cancer diagnosis has remarkably improved, but emerging evidence suggests that cancer-directed therapy may have adverse gastrointestinal late effects. We aimed to comprehensively assess the frequency of gastrointestinal and liver late effects among childhood cancer survivors and compare this frequency with the general population. Our population-based cohort study included all 1-year survivors of childhood and adolescent cancer in Denmark, Finland, Iceland, Norway and Sweden diagnosed from the 1940s and 1950s. Our outcomes of interest were hospitalization rates for gastrointestinal and liver diseases, which were ascertained from national patient registries. We calculated standardized hospitalization rate ratios (RRs) and absolute excess rates comparing hospitalizations of any gastrointestinal or liver disease and for specific disease entities between survivors and the general population. The study included 31,132 survivors and 207,041 comparison subjects. The median follow-up in the hospital registries were 10 years (range: 0-42) with 23% of the survivors being followed at least to the age of 40 years. Overall, survivors had a 60% relative excess of gastrointestinal or liver diseases [RR: 1.6, 95% confidence interval (CI): 1.6-1.7], which corresponds to an absolute excess of 360 (95% CI: 330-390) hospitalizations per 100,000 person-years. Survivors of hepatic tumors, neuroblastoma and leukemia had the highest excess of gastrointestinal and liver diseases. In addition, we observed a relative excess of several specific diseases such as esophageal stricture (RR: 13; 95% CI: 9.2-20) and liver cirrhosis (RR: 2.9; 95% CI: 2.0-4.1). Our findings provide useful information about the breadth and magnitude of late complications among childhood cancer survivors and can be used for generating hypotheses about potential exposures related to these gastrointestinal and liver late effects.

The Adult Life After Childhood Cancer in Scandinavia (ALiCCS) Study: Design and Characteristics.

BACKGROUND: During the last five decades, survival of childhood cancer has increased from 25% to 80%. At the same time, however, it has become evident that survivors experience a broad range of therapy-related late adverse health effects. The aim of the Adult Life after Childhood Cancer in Scandinavia (ALiCCS) study is to investigate long-term health consequences of past and current therapies in order to improve follow-up care of survivors and to reduce treatment-related morbidity of future patients. PROCEDURE: Childhood cancer survivors were identified through the five Nordic cancer registries and a comparison cohort was established through random selection of cancer-free individuals from the civil registration systems. A unique personal identification number was used to link between different health registries. Abstraction of treatment information for a subset of survivors allows investigation of the association between the various components of cancer therapy and late occurring comorbidity. RESULTS: The childhood cancer survivor cohort comprises 33,160 1-year survivors and the comparison cohort comprises 212,892 cancer free individuals from the general population. In the childhood cancer survivor cohort, all types of childhood cancer are represented including leukemia (21%), lymphoma (14%), central nervous system tumors (24%), sarcomas (5%), retinoblastoma (3%), and neuroblastoma (4%). Among the survivors, 22% have been followed beyond the age of 40 years. CONCLUSION: The ALiCCS study constitutes a new large resource for research on late effects of childhood cancers that include all types of childhood malignancies and has followed a large proportion of the survivors well into late adulthood.