The Swiss Childhood Cancer Registry: rationale, organisation and results for the years 2001-2005

QUESTIONS UNDER STUDY: Childhood cancer is a rare but severe disease. Therefore central registration of all cases is essential for surveillance and management. This paper describes the methodology and basic results of the Swiss Childhood Cancer Registry (SCCR). METHODS: The SCCR was established in 1976, originally as a national hospital-based registry of childhood malignancies. All 9 paediatric oncology-haematology clinics in Switzerland provide baseline and follow-up information on all children diagnosed with cancer. These data are registered centrally and diagnoses are coded according to the International Classification of Childhood Cancer. RESULTS: From 2001-2005, 887 cases of childhood cancer in Swiss residents under the age of 15 years were registered in the SCCR. Of these, 281 (31.7%) were leukaemias, 223 (24.0%) were CNS tumours, and 116 (13.1%) were lymphomas. The age-standardised annual incidence per 1 Million person-years (age below 15 years; world standardisation) was 154.0 (95% CI 143.7-164.3; N = 887). The incidence was higher for boys (170.2, 155.0-185.4; N = 501) than for girls (136.9, 123.0-150.8; N = 386). CONCLUSION: The close collaboration between all paediatric oncologists-haematologists in Switzerland and a university department allowed the creation of a national population-based cancer registry with detailed clinical information. The SCCR produces cancer type specific incidence and survival estimates and allows the development of nested research projects on childhood cancer aetiology, management and outcome, both on a national and on an international level.

Incidence of childhood cancer in Switzerland: the Swiss Childhood Cancer Registry

BACKGROUND: This report describes the incidence of childhood cancer in Switzerland, based on the data from the Swiss Childhood Cancer Registry (SCCR), a national hospital-based cancer registry with very high coverage, founded in 1976 by the Swiss Paediatric Oncology Group (SPOG). PROCEDURE: Malignancies were coded according to the International Classification of Childhood Cancer (ICCC-3). Incidence rates per 100,000 person-years were calculated for all malignancies and groups of malignancies in Swiss residents less than 15 years of age for the decade 1995-2004. RESULTS: The SCCR annually registered on average 174 new cases of cancer in Swiss residents aged <15 years, with a median age at diagnosis of 5.6 years. The crude incidence of childhood cancer in children aged <15 years was 13.5, higher for boys (15.0 per 100,000) than for girls (12.1 per 100,000), and was nearly twice as high in the first 5 years of life (19.3 per 100,000) than in the age group 5 to 14 years (10.8 per 100,000). CONCLUSION: Incidence of childhood cancers in the SCCR was similar to neighbouring countries and to data published by regional cancer registries in Switzerland for the same period, suggesting good completeness of registration. This makes the SCCR a valuable resource for national and international research on childhood cancer.

The Swiss Canine Cancer Registry: a retrospective study on the occurrence of tumours in dogs in Switzerland from 1955 to 2008

Diagnostic records are a key feature of any cancer epidemiology, prevention or control strategy for man and animals. Therefore, the information stored in human and animal cancer registries is essential for undertaking comparative epidemiological, pathogenic and therapeutic research. This study presents the Swiss Canine Cancer Registry, containing case data compiled between 1955 and 2008. The data consist of pathology diagnostic records issued by three veterinary diagnostic laboratories in Switzerland. The tumours were classified according to the guidelines of the International Classification of Oncology for Humans on the basis of tumour type, malignancy and body location. The dogs were classified according to breed, age, sex, neuter status and place of residence. The diagnostic data were correlated with data on the Swiss general dog population and the incidence of cancer in dogs was thus investigated. A total of 67,943 tumours were diagnosed in 121,963 dogs and 47.07% of these were malignant. The most common tumour location was the skin (37.05%), followed by mammary glands (23.55%) and soft tissue (13.66%). The most common tumour diagnoses were epithelial (38.45%), mesenchymal (35.10%) and lymphoid tumours (13.23%). The results are compared with data in other canine registries and similarities in tumour distribution and incidence are noted. It is hoped that this study will mark the beginning of continuous registration of dog tumours in Switzerland, which, in turn, will serve as a reference for research in the fields of animal and human oncology.

Swiss Feline Cancer Registry: A Retrospective Study of the Occurrence of Tumours in Cats in Switzerland from 1965 to 2008

Cancer is one of the leading causes of death in companion animals. Information on the epidemiology of cancer is instrumental for veterinary practitioners in patient management; however, spontaneously arising tumours in companion animals also resemble those in man and can provide useful data in combating cancer. Veterinary cancer registries for cats are few in number and have often remained short-lived. This paper presents a retrospective study of tumours in cats in Switzerland from 1965 to 2008. Tumour diagnoses were coded according to topographical and morphological keys of the International Classification of Oncology for Humans (ICD-O-3). Correlations between breed, sex and age were then examined using a multiple logistic regression model. A total of 18,375 tumours were diagnosed in 51,322 cats. Of these, 14,759 (80.3%) tumours were malignant. Several breeds had significantly lower odds ratios for developing a tumour compared with European shorthair cats. The odds of a cat developing a tumour increased with age, up to the age of 16 years, and female cats had higher risk of developing a tumour compared with male cats. Skin (4,970; 27.05%) was the most frequent location for tumours, followed by connective tissue (3,498; 19.04%), unknown location (2,532; 13.78%) and female sexual organs (1,564; 8.51%). The most common tumour types were epithelial tumours (7,913; 43.06%), mesenchymal tumours (5,142; 27.98%) and lymphoid tumours (3,911; 21.28%).

Can health beliefs help in explaining attendance to follow-up care? The Swiss Childhood Cancer Survivor Study

Objective: Improved treatment has increased the survival of childhood cancer patients in recent decades, but follow-up care is recommended to detect and treat late effects. We investigated relationships between health beliefs and follow-up attendance in adult childhood cancer survivors. Methods: Childhood cancer survivors aged younger than 16 years when diagnosed between 1976 and 2003, who had survived for more than 5 years and were currently aged 201 years, received a postal questionnaire. We asked survivors whether they attended follow-up in the past year. Concepts from the Health Belief Model (perceived susceptibility and severity of future late effects, potential benefits and barriers to follow-up, general health value and cues to action) were assessed. Medical information was extracted from the Swiss Childhood Cancer Registry. Results: Of 1075 survivors (response rate 72.3%), 250 (23.3%) still attended regular followup care. In unadjusted analyses, all health belief concepts were significantly associated with follow-up (po0.05). Adjusting for other health beliefs, demographic, and medical variables, only barriers (OR50.59; 95%CI: 0.43–0.82) remained significant. Younger survivors, those with lower educational background, diagnosed at an older age, treated with chemotherapy, radiotherapy, or bone marrow transplantation and with a relapse were more likely to attend follow-up care. Conclusions: Our study showed that more survivors at high risk of cancer- and treatmentrelated late effects attend follow-up care in Switzerland. Patient-perceived barriers hinder attendance even after accounting for medical variables. Information about the potential effectiveness and value of follow-up needs to be available to increase the attendance among childhood cancer survivors.

Childhood cancer and nuclear power plants in Switzerland: a census-based cohort study

Background Previous studies on childhood cancer and nuclear power plants (NPPs) produced conflicting results. We used a cohort approach to examine whether residence near NPPs was associated with leukaemia or any childhood cancer in Switzerland. Methods We computed person-years at risk for children aged 0–15 years born in Switzerland from 1985 to 2009, based on the Swiss censuses 1990 and 2000 and identified cancer cases from the Swiss Childhood Cancer Registry. We geo-coded place of residence at birth and calculated incidence rate ratios (IRRs) with 95% confidence intervals (CIs) comparing the risk of cancer in children born <5 km, 5–10 km and 10–15 km from the nearest NPP with children born >15 km away, using Poisson regression models. Results We included 2925 children diagnosed with cancer during 21 117 524 person-years of follow-up; 953 (32.6%) had leukaemia. Eight and 12 children diagnosed with leukaemia at ages 0–4 and 0–15 years, and 18 and 31 children diagnosed with any cancer were born <5 km from a NPP. Compared with children born >15 km away, the IRRs (95% CI) for leukaemia in 0–4 and 0–15 year olds were 1.20 (0.60–2.41) and 1.05 (0.60–1.86), respectively. For any cancer, corresponding IRRs were 0.97 (0.61–1.54) and 0.89 (0.63–1.27). There was no evidence of a dose–response relationship with distance (P > 0.30). Results were similar for residence at diagnosis and at birth, and when adjusted for potential confounders. Results from sensitivity analyses were consistent with main results. Conclusions This nationwide cohort study found little evidence of an association between residence near NPPs and the risk of leukaemia or any childhood cancer.

Daily Physical Activities and Sports in Adult Survivors of Childhood Cancer and Healthy Controls: A Population-Based Questionnaire Survey

Background Healthy lifestyle including sufficient physical activity may mitigate or prevent adverse long-term effects of childhood cancer. We described daily physical activities and sports in childhood cancer survivors and controls, and assessed determinants of both activity patterns. Methodology/Principal Findings The Swiss Childhood Cancer Survivor Study is a questionnaire survey including all children diagnosed with cancer 1976–2003 at age 0–15 years, registered in the Swiss Childhood Cancer Registry, who survived ≥5years and reached adulthood (≥20years). Controls came from the population-based Swiss Health Survey. We compared the two populations and determined risk factors for both outcomes in separate multivariable logistic regression models. The sample included 1058 survivors and 5593 controls (response rates 78% and 66%). Sufficient daily physical activities were reported by 52% (n = 521) of survivors and 37% (n = 2069) of controls (p<0.001). In contrast, 62% (n = 640) of survivors and 65% (n = 3635) of controls reported engaging in sports (p = 0.067). Risk factors for insufficient daily activities in both populations were: older age (OR for ≥35years: 1.5, 95CI 1.2–2.0), female gender (OR 1.6, 95CI 1.3–1.9), French/Italian Speaking (OR 1.4, 95CI 1.1–1.7), and higher education (OR for university education: 2.0, 95CI 1.5–2.6). Risk factors for no sports were: being a survivor (OR 1.3, 95CI 1.1–1.6), older age (OR for ≥35years: 1.4, 95CI 1.1–1.8), migration background (OR 1.5, 95CI 1.3–1.8), French/Italian speaking (OR 1.4, 95CI 1.2–1.7), lower education (OR for compulsory schooling only: 1.6, 95CI 1.2–2.2), being married (OR 1.7, 95CI 1.5–2.0), having children (OR 1.3, 95CI 1.4–1.9), obesity (OR 2.4, 95CI 1.7–3.3), and smoking (OR 1.7, 95CI 1.5–2.1). Type of diagnosis was only associated with sports. Conclusions/Significance Physical activity levels in survivors were lower than recommended, but comparable to controls and mainly determined by socio-demographic and cultural factors. Strategies to improve physical activity levels could be similar as for the general population.

Physical performance limitations in adolescent and adult survivors of childhood cancer and their siblings

Purpose This study investigates physical performance limitations for sports and daily activities in recently diagnosed childhood cancer survivors and siblings. Methods The Swiss Childhood Cancer Survivor Study sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976–2003 aged <16 years. Siblings received similar questionnaires. We assessed two types of physical performance limitations: 1) limitations in sports; 2) limitations in daily activities (using SF-36 physical function score). We compared results between survivors diagnosed before and after 1990 and determined predictors for both types of limitations by multivariable logistic regression. Results The sample included 1038 survivors and 534 siblings. Overall, 96 survivors (9.5%) and 7 siblings (1.1%) reported a limitation in sports (Odds ratio 5.5, 95%CI 2.9-10.4, p<0.001), mainly caused by musculoskeletal and neurological problems. Findings were even more pronounced for children diagnosed more recently (OR 4.8, CI 2.4–9.6 and 8.3, CI 3.7–18.8 for those diagnosed <1990 and ≥1990, respectively; p = 0.025). Mean physical function score for limitations in daily activities was 49.6 (CI 48.9–50.4) in survivors and 53.1 (CI 52.5–53.7) in siblings (p<0.001). Again, differences tended to be larger in children diagnosed more recently. Survivors of bone tumors, CNS tumors and retinoblastoma and children treated with radiotherapy were most strongly affected. Conclusion Survivors of childhood cancer, even those diagnosed recently and treated with modern protocols, remain at high risk for physical performance limitations. Treatment and follow-up care should include tailored interventions to mitigate these late effects in high-risk patients.

Life partnerships in childhood cancer survivors, their siblings, and the general population

Background: Life partnerships other than marriage are rarely studied in childhood cancer survivors (CCS). We aimed (1) to describe life partnership and marriage in CCS and compare them to life partnerships in siblings and the general population; and (2) to identify socio-demographic and cancer-related factors associated with life partnership and marriage. Methods: As part of the Swiss Childhood Cancer Survivor Study (SCCSS), a questionnaire was sent to all CCS (aged 20–40 years) registered in the Swiss Childhood Cancer Registry (SCCR), aged <16 years at diagnosis, who had survived ≥5 years. The proportion with life partner or married was compared between CSS and siblings and participants in the Swiss Health Survey (SHS). Multivariable logistic regression was used to identify factors associated with life partnership or marriage. Results: We included 1,096 CCS of the SCCSS, 500 siblings and 5,593 participants of the SHS. Fewer CCS (47%) than siblings (61%, P < 0.001) had life partners, and fewer CCS were married (16%) than among the SHS population (26%, P > 0.001). Older (OR = 1.14, P < 0.001) and female CCS (OR = 1.85, <0.001) were more likely to have life partners. CCS who had undergone radiotherapy, bone marrow transplants (global PTreatment = 0.018) or who had a CNS diagnosis (global PDiagnosis < 0.001) were less likely to have life partners. Conclusion: CCS are less likely to have life partners than their peers. Most CCS with a life partner were not married. Future research should focus on the effect of these disparities on the quality of life of CCS.

Health-related quality of life in survivors of childhood cancer: the role of chronic health problems

INTRODUCTION The influence of specific health problems on health-related quality of life (HRQoL) in childhood cancer survivors is unknown. We compared HRQoL between survivors of childhood cancer and their siblings, determined factors associated with HRQoL, and investigated the influence of chronic health problems on HRQoL. METHODS Within the Swiss Childhood Cancer Survivor Study, we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. Siblings received similar questionnaires. We assessed HRQoL using Short Form-36 (SF-36). Health problems from a standard questionnaire were classified into overweight, vision impairment, hearing, memory, digestive, musculoskeletal or neurological, and thyroid problems. RESULTS The sample included 1,593 survivors and 695 siblings. Survivors scored significantly lower than siblings in physical function, role limitation, general health, and the Physical Component Summary (PCS). Lower score in PCS was associated with a diagnosis of central nervous system tumor, retinoblastoma or bone tumor, having had surgery, cranio-spinal irradiation, or bone marrow transplantation. Lower score in Mental Component Summary was associated with older age. All health problems decreased HRQoL in all scales. Most affected were survivors reporting memory problems and musculoskeletal or neurological problems. Health problems had the biggest impact on physical functioning, general health, and energy and vitality. CONCLUSIONS In this study, we showed the negative impact of specific chronic health problems on survivors' HRQoL. IMPLICATIONS FOR CANCER SURVIVORS Therapeutic preventive measures, risk-targeted follow-up, and interventions might help decrease health problems and, consequently, improve survivors' quality of life.

Incident malignancies among older long-term breast cancer survivors and an age-matched and site-matched nonbreast cancer comparison group over 10 years of follow-up

BACKGROUND Of the approximately 2.4 million American women with a history of breast cancer, 43% are aged ≥ 65 years and are at risk for developing subsequent malignancies. METHODS Women from 6 geographically diverse sites included 5-year breast cancer survivors (N = 1361) who were diagnosed between 1990 and 1994 at age ≥ 65 years with stage I or II disease and a comparison group of women without breast cancer (N = 1361). Women in the comparison group were age-matched and site-matched to breast cancer survivors on the date of breast cancer diagnosis. Follow-up began 5 years after the index date (survivor diagnosis date or comparison enrollment date) until death, disenrollment, or through 15 years after the index date. Data were collected from medical records and electronic sources (cancer registry, administrative, clinical, National Death Index). Analyses included descriptive statistics, crude incidence rates, and Cox proportional hazards regression models for estimating the risk of incident malignancy and were adjusted for death as a competing risk. RESULTS Survivors and women in the comparison group were similar: >82% were white, 55% had a Charlson Comorbidity Index of 0, and ≥ 73% had a body mass index ≤ 30 kg/m(2) . Of all 306 women (N = 160 in the survivor group, N = 146 in the comparison group) who developed a first incident malignancy during follow-up, the mean time to malignancy was similar (4.37 ± 2.81 years vs 4.03 ± 2.76 years, respectively; P = .28), whereas unadjusted incidence rates were slightly higher in survivors (1882 vs 1620 per 100,000 person years). The adjusted hazard of developing a first incident malignancy was slightly elevated in survivors in relation to women in the comparison group, but it was not statistically significant (hazard ratio, 1.17; 95% confidence interval, 0.94-1.47). CONCLUSIONS Older women who survived 5 years after an early stage breast cancer diagnosis were not at an elevated risk for developing subsequent incident malignancies up to 15 years after their breast cancer diagnosis.

Do childhood cancer survivors with physical performance limitations reach healthy activity levels?

BACKGROUND The extent to which physical performance limitations affect the ability of childhood cancer survivors to reach healthy activity levels is unknown. Therefore this study aims to describe the effect of different types of limitations on activity levels in survivors. PROCEDURE Within the Swiss Childhood Cancer Survivor Study we sent a questionnaire to all survivors (≥16 years) registered in the Swiss Childhood Cancer Registry, who survived >5 years and were diagnosed 1976-2005 aged <16 years. We measured healthy activity levels using international guidelines and assessed different kinds of performance limitations (visual impairment, weight and endurance problems, cardiorespiratory, musculoskeletal, and neurological problems, pain and fatigue syndromes). RESULTS The sample included 1,560 survivors (75% response rate), of whom 209 (13.5%) reported they have performance limitations. Forty-two percent of survivors with limitations reached healthy activity levels, compared to 57% of survivors without limitations. Least active were survivors with vision impairments (25% active), weight and endurance problems (27.3%), cardiorespiratory problems (36.4%), and musculoskeletal problems (43.1%). After adjusting for socio-demographic variables and type of cancer, we found that survivors with limitations were 1.4 (95%CI 1.0-2.0; P = 0.047) times more likely to be inactive. CONCLUSIONS Although many survivors with physical performance limitations maintain healthy activity levels, there is room for improvement. Adapted and targeted physical activity counseling for survivors with performance limitations might help them to raise level of activity and pursue a healthy lifestyle.