This prospective one year follow-up study in children and adolescents with newly diagnosed cancer found several domains of HRQOL to be markedly compromised. Notably, compared to a community sample, children reported a diminished quality of life in the physical, motor and emotional domains. In addition, 6 weeks after diagnosis children reported impaired autonomy. The diminishment of quality of life was more pronounced 6 weeks after diagnosis than at the one year follow-up where HRQOL was found to be reduced in only two domains. These results are consistent with our hypothesis and confirm earlier findings by Eiser et al.  on significant improvement of mother-reported HRQOL in children with leukemia between a 3–6 months and a one year follow-up. Comparisons between children with different types of cancer in our study revealed that at 6 weeks after diagnosis children with leukemia were the most affected in the majority of dimensions of HRQOL. At one year, however, children with brain tumors seemed to be the most affected although the differences between groups were not statistically significant. This is in line with earlier findings by Meeske et al.  who found patients with brain tumors to exhibit more problems than patients with leukemia in the physical, social, psychosocial, and cognitive domains of HRQOL. Clearly, the various groups of pediatric cancer patients are differently affected with regard to their HRQOL. Probably, these differences are due to different treatment protocols. Typically, children with leukemia undergoing chemotherapy suffer from significant treatment-related acute toxicity during the initial induction phase of their treatment protocol. This particular toxicity is less pronounced for children undergoing treatment protocols for brain tumors. This is the first prospective study to show that the most affected diagnostic groups may change over time. Contrary to the suggestion of Meeske et al.  we cannot support the notion that patients with leukemia only have minimal changes in HRQOL during the active treatment. In fact, children with leukemia had the most significant improvements between 6 weeks and one year.
This study also analyzed various individual, medical, and parental correlates of child HRQOL. Consistent with our hypothesis medical and treatment variables, such as intensity of therapy and medical complications were associated with HRQOL. As can be expected, the influence of medical variables was more pronounced at 6 weeks than at one year after diagnosis. Thus, the influence of medical and treatment variables on HRQOL gets smaller over the course of treatment which may be due to adjustment processes and a reduction of treatment intensity. However, ongoing medical complications and an impaired functional status still affected emotional domains of HRQOL in a negative way after one year. Thus, increased long-term medical problems negatively impact on emotional functioning. Demographic factors such as age and sex showed particularly strong associations with some domains of HRQOL at 6 weeks but less at one year. In our sample, younger children had a higher risk for HRQOL problems than older children. Also, boys reported fewer problems in the domains of cognitive and emotional functioning. The higher vulnerability of girls with regard to HRQOL problems is well known from other studies [2, 5].
To our knowledge this is the first study to show associations between parental psychological adjustment and child self-reported HRQOL in pediatric cancer patients. These findings are all the more important as different informants were used for the assessment of parental mental and child HRQOL, respectively, excluding shared method variance as an explanation. In general, better parental adjustment was associated with better HRQOL in the child, particularly in the emotional domain, six weeks after diagnosis. Surprisingly, however, better maternal and paternal adjustment were associated with poorer HRQOL in the child in the cognitive and social domains. This contradicts previous studies that found family problems to negatively affect HRQOL in children with chronic conditions, such as phenylketonuria or nephrotic syndrome [17, 19]. Certainly, the pathways of parental influence on the HRQOL of children with chronic health conditions are not yet well understood and need to be further studied in future.
Strengths of this study comprise its use of multiple sources of information (patients, mothers, fathers, physicians) and its multidimensional and highly standardized assessment of HRQOL in a prospective design. Moreover, sample patients are representative for newly diagnosed children aged 6–15 years in Switzerland. Nonetheless, some limitations merit note. First, our sample is rather small, making statistically significant findings more difficult to achieve and limiting comparisons of diagnostic subgroups. Second, our response rate was only 63%. Although we compared non-participants and participants with regard to demographic characteristics and medical diagnosis we do not know whether these two groups systematically differed regarding their HRQOL. Third, our HRQOL instrument is a generic measure not specifically designed for pediatric cancer. Therefore, it may lack sensitivity for specific problems of this group. However, the TACQOL has successfully been used in a variety of different chronic diseases and has been shown to be a valid and reliable measure allowing comparison with healthy references. Moreover, a German cancer specific HRQOL measure was only published after this study had been completed . Fourth, appropriateness of Dutch HRQOL norms for our sample of Swiss children can be questioned. However, since the Netherlands and Switzerland are European countries with similar social structures, a major cross-cultural bias seems unlikely. This is confirmed by a recent European study in children with chronic diseases that found HRQOL to be higher in Nordic countries compared to Greece and the UK . However, children from central European countries such as Germany and The Netherlands reported very similar HRQOL. This supports the notion that Dutch norms may be used for Swiss children. Finally, there may be some concerns regarding our correlational findings, since the chance of falsely significant results increases with the number of comparisons performed on the same set of data. Because this study had an exploratory character and the limited sample size did not allow multivariate analyses, subsequent studies are needed to confirm the findings.
Our data suggest some possible issues for future research activities. First, this study confirmed that the assessment of HRQOL in children is important and yields valid results. Hopefully, in the future, HRQOL will be considered as an important variable in the evaluation of new medical treatments and standardized HRQOL assessment will be routinely incorporated into therapeutic cancer trials. HRQOL research can be used to optimize treatment and to give important information for decision making if treatment strategies with similar survival rates are compared . Certainly, prospective studies of larger samples of children undergoing active cancer treatment are necessary. Repeated assessments will allow analysis of the course of the disease and the medical, individual and familial predictors of HRQOL over time, as well as more detailed comparisons of different oncological groups. Also, the importance of parental and familial variables on child HRQOL should be studied in more details because this may be important for designing appropriate family-based interventions in children with newly diagnosed cancer. Probably, findings from studies in pediatric cancer patients showing the importance of parental variables for psychological adjustment can be adopted into the research on HRQOL.
There are some clinical implications that can be drawn from this study. Our findings confirm the need for repeated careful evaluation of HRQOL in children who are undergoing active cancer treatment. Our data show that there might be significant differences in HRQOL between diagnostic groups that need to be considered in psychosocial treatment programs in order to improve HRQOL in children with cancer. Psychosocial interventions may not only have to be specifically tailored for diagnostic groups but also for different stages of treatment. Moreover, this study suggests that the whole family needs to be targeted in order to improve the HRQOL in children and adolescents with cancer.