Opportunities for cancer prevention in adolescents range from limitation of sun exposure to the use of human papillomavirus vaccines. Those who develop malignant disease experience longer waiting times for diagnosis and treatment than do children, especially when referred to adult treatment centers, and they are less frequently enrolled in clinical trials. More attention to developmentally appropriate psychological support, enhancement of compliance/adherence, health promotion, and palliative care is needed. Improving cancer surveillance and control in adolescents in North America will require co-ordinated national efforts, involving pediatric and adult health care providers, institutions, and multiple levels of government.
Two childhood cancer registries exist in Ontario. One (POGO) accrues by active registration by pediatric cancer centers, utilizing a histologically based classification system. The other accrues by passive linkage within a larger adult oriented cancer registry (OCR) using a topographically based classification. A reportedly high incidence of childhood cancer based on the latter registry prompted a comparison of the content of the two registries over a 2-year period with the hypothesis that there would be systematic accrual errors. All registrations in both registries for the specified period were reviewed systematically and validated by pathology reports. A small number (2.6%) of registrations in the passive registry were not incident cases, while 2 particular pathologic diagnoses were included in the histologically based registry and not the topographically based registry. These were low grade gliomas and Langerhans cell histiocytosis (LCH). The validated annual incident rate (15.6 per 100000 children 0-14 years of age, excluding LCH) is slightly higher than that reported in other industrialized countries. Ninety-six percent of children aged 0-14 were treated in pediatric oncology centers, while only 46% of adolescents aged 15-17 were treated in such centers. Of the remaining adolescents, more than one-third had lymphomas. This maldistribution of care provided for the young adolescent population may compromise their survival prospects. The results of this study should prompt revision of health care policy and patterns of service delivery.
Adolescence, spanning 15-19 years of age, is a time of developmental transition from childhood to adult life. The spectrum of cancers affecting this age group reflects a similar transition. The common malignant diseases of childhood - leukemias, lymphomas, tumors of the central nervous system and embryonal solid tumors (such as nephroblastoma and neuroblastoma) - are replaced in relative frequency by sarcomas of bone and soft tissue, and tumors of the male and female genital tracts. Moreover, the epithelial tumors (carcinomas), so prevalent in adults, occur (albeit at much lower frequencies) in adolescents. Within individual tumor types, biological features may be distinctive in this age group. Examples are the high prevalence of poor prognostic determinants in acute lymphoblastic leukemia and histologically higher grade forms of astrocytic/glial tumors. Particular challenges in addressing the common tumors of adolescence include the development of better categorization, especially of soft tissue sarcomas, and exploring these diseases in this age group within the developing world where most adolescents reside.
Few studies have investigated delays in diagnosis and treatment among children and adolescents with cancer, especially from the perspective of an entire country. Detailed understanding of delays along the continuum of cancer patient care is important in order to establish appropriate benchmarks for timely oncological care. Our objective was to characterise the different components of delay in 2,896 Canadian children and adolescents (aged 0-19 years) with cancer that were enrolled in the Treatment and Outcome Surveillance component of the Canadian Childhood Cancer Surveillance and Control Program from 1995 to 2000.
We examined median and standardised means concerning the distribution of delay times across categories of pertinent variables and over time. The word "delay" was used simply to represent a time interval, measured in days, without implying whether this interval exceeded a particular threshold of clinical acceptability.
The median times (and inter-quartile ranges) for patient, diagnosis and healthcare system delays for all cancers were 9 (1-31), 30 (13-69) and 12 (4-35) days, respectively. The median total delay was 34 (16-76) days.
Patient and referral delays were the longest time segments influencing timely diagnosis. Differences in delays were observed across age groups, cancer types and geographical regions. There was a significant trend for decreasing delays to diagnosis and treatment.
Minimizing delays that may occur along the cancer care pathway requires an understanding of their determinants. Few studies on childhood cancers have been published on the factors that influence the time it takes for patients to get a first medical consultation (patient delay) and treatment (health care system [HCS] delay) once cancer symptoms have been recognized. Our objective was to assess factors related to disease, patient and HCS on patient and HCS delay for children and adolescents with leukemias and lymphomas in Canada. A prospective cohort study was conducted on subjects enrolled in the Treatment and Outcomes Surveillance program of the Canadian Childhood Cancer Surveillance and Control Program, a national surveillance program. We studied 963 leukemia and 397 lymphoma patients who were less than 19-years old at diagnosis in 1995-2000. Logistic regression models were used to measure the associations between candidate predictive factors and delays. Age was positively associated with patient delay for both leukemia and lymphoma patients, but not with HCS delay. Patients first seen in a hospital emergency room had a lower risk of HCS delay than patients first seen by a general practitioner. Cancer subtype was associated with patient delay for leukemia patients, and HCS delay for lymphoma patients. Longer patient delay was associated with a lower risk of long HCS delay for both cancers. Factors related to the patients, their disease and the HCS may exert different influences on varying segments of the care pathway of leukemia and lymphoma patients.
Evidence about HUI and hemophilia in response to Young et al. "How well does the Canadian hemophilia outcomes-kids' life assessment tool (CHO-KLAT) measure the quality of life of boys with hemophilia?".
Von Willebrand disease (VWD) is the commonest inherited disorder of hemostasis and the majority of women with this disorder experience excessive uterine bleeding. Yet very little information is available on the health-related quality of life (HRQL) in individuals with VWD. To test the a priori hypotheses that these individuals will have poorer HRQL than members of the general population, and that this burden of morbidity will correlate with the severity of VWD, a cross-sectional study was undertaken of a population-based cohort in a regional hemophilia program in Ontario, Canada. A survey was made of individuals over 13 years of age with VWD who self-reported their health status using a standard 15 item questionnaire. The responses were converted to levels in the Health Utilities Index Mark 2 (HUI2) and Mark 3 (HUI3) health status classification systems to form multi-element vectors from which single attribute morbidity and overall HRQL utility scores were determined. As a group, individuals with VWD were shown to have poorer HRQL than members of the general population and those with Type 2 disease carried a greater burden of overall morbidity than those with Type 1 disorder. Morbidity was evident mainly in the attributes of emotion, cognition with pain. A striking difference was observed between males and females, with the latter having overall HRQL utility scores similar to those reported previously for HIV positive, severe hemophiliacs. It is possible that this remarkable burden of morbidity reflects chronic iron deficiency associated with menorrhagia. A national study has been proposed to address this likelihood as it offers an opportunity for effective therapeutic intervention (iron supplementation) with a concomitant gain in health status and HRQL.
Assessing health status in survivors of childhood cancer is increasingly important due to improved survival rates. However, there are limited estimates available for this population based on large samples and compared to population controls.
In a retrospective cohort study, 2,152 long-term survivors and 2,432 controls, aged 5-37, who had survived cancer during childhood or adolescence were compared on the Health Utilities Index Mark III (HUI3). Descriptive and logistic regression analyses were used to assess the effect of age at diagnosis, type of cancer and therapy received on HUI3 domains.
More survivors than controls showed deficits in dexterity, ambulation, hearing, speech and cognition but not in vision, emotion or pain. The largest numbers of survivors reporting excess impairment was found in the cognition attribute. Survivors of central nervous system tumors were most likely to show impairments across multiple domains. Lastly, impairments in cognition were found most commonly in survivors exposed to cranio-spinal radiation at young ages.
Seventy-five percent of childhood cancer survivors and 80% of controls were found to have two or fewer impaired attributes. Those reporting impairments that were most likely to be of clinical relevance were among survivors diagnosed with central nervous system and bone tumours, and those exposed to cranial radiation as young children. Tools assessing health status should be included in prospective trials to more clearly assess the contribution of therapy to reduced long-term health status.
Comment In: Qual Life Res. 2006 Feb;15(1):159-6016411039