1. Introduction
Survival rates for childhood cancer diagnosed before the age of 18 years have improved due to aggressive multidisciplinary therapeutic approaches. With the improvement of survival rates, much attention has been focused on the psychosocial functioning of children with cancer.
Most research into psychosocial functioning in children with cancer has shown that symptoms of depression and anxiety decreased over time [
1,
2,
3,
4]. There is also some evidence that behavioral difficulties in these children were slightly increased compared to healthy children [
5]. On the other hand, research into psychosocial functioning in adults surviving childhood cancer revealed that certain groups among them rarely obtain advanced education, get a job, or get married, compared to the normal population [
6]. These inconsistent results indicate that there can be prolonged psychosocial difficulties from surviving childhood cancer that cannot be evaluated sufficiently by a self-reported questionnaire regarding depression and anxiety. More of the multi-faceted aspects of the psychosocial functioning of children with cancer should be evaluated.
Previous research on the psychosocial functioning of parents of children with cancer also revealed inconsistent results. Parental emotional difficulties, such as depression and anxiety, have been reported to decrease after cancer treatment [
7,
8]. However, many parents continue to experience chronic post-traumatic stress (PTS) for a long time after their child’s treatment [
9]. PTS symptoms (PTSS) consist of a continuum of key symptoms of PTS disease (PTSD). Assessment of PTSS has proven to be more broadly applicable to the treatment of children with cancer and their parents than formally confirming the PTSD diagnosis is [
10]. Parents also reported persistent feelings of loss, uncertainty, and anxiety about the recurrence of the disease or the emergence of late effects in their child. Such illness-specific distress of the parents should be assessed in order to fully understand their psychosocial functioning [
11,
12].
Parental psychosocial functioning has been found to be positively correlated with psychosocial functioning in children [
13,
14]. Parents of children with cancer are the most important emotional resources for the child, and parents who have severe distress and PTSS may well have difficulty caring for their children. Children with cancer whose parents have severe distress and PTSS may receive insufficient emotional support and have difficulties coping with their situation. In addition, previous studies revealed that support from peers is important for adolescents with cancer [
15].
The psychosocial functioning of the child with cancer, illness-specific distress, and PTSS of the parents will be influenced by demographic and medical factors, such as the child’s age at diagnosis or the type of treatment. Many previous studies have shown that objective medical factors, such as the severity of disease and the intensity of treatment, are not associated with the psychosocial functioning of children with cancer. However, many of those studies excluded children who received relatively intensive treatment, such as for brain tumors [
16,
17]. The comparison of the severity or intensity of treatment of childhood cancer is difficult because these cancers are a heterogeneous mix.
Compared to western countries, the trend of parents making a full disclosure of the child’s diagnosis has progressed slowly in Japan [
18,
19]. However, even in cultures in which full disclosure is a common practice, parents often find it difficult to tell their child about the disease [
20,
21]. In western countries, the benefits of truthful disclosure have been examined [
8,
21,
22,
23], but there have been few such studies in Japan [
24].
The purposes of this study were threefold. The first was to determine the proportions of children with cancer having a range of clinically relevant emotional and behavioral problems and the proportion of their parents having PTSS. The second was to clarify whether there were any associations between the children’s behavioral functioning and their parents’ psychosocial functioning. The third was to explore demographic, medical, and social factors associated with these children’s behavioral functioning and with their parents’ psychosocial functioning.
We hypothesized that parental distress and PTSS are associated with the emotional and behavioral functioning of children with cancer. In addition, we hypothesized that the intensity of treatment and social factors will be associated with parental distress, PTSS and the emotional and behavioral functioning of children with cancer.
4. Discussion
Our study indicated that approximately one-quarter of the children with cancer had clinical general behavioral problems: internalizing problems such as anxiety, depression, or social withdrawal; or externalizing problems such as antisocial and aggressive behavior. The mean CBCL total problems
T score in the present study was similar to that reported by Barrera et al. for children diagnosed within the past three months (52.5 ± 10.9) and to that reported in a study of children diagnosed with cancer, excluding brain tumor, within the past four months (49.5 ± 12.0), all within the clinically relevant range [
5,
31]. We found that emotional and behavioral difficulties in some children with cancer persist for a long time after treatment.
Approximately one-quarter of parents of a child with cancer had PTSS. The proportion of parents having PTSS in the present study was similar to that of a previous study in Japan reported by Ozono (20.7% of mothers, 22.6% of fathers) [
32], although it was lower than that in a childhood brain tumor survivor study reported by Bruce et al. (29%) [
33]. The mean IES-R score for parents in the present study was also similar to that reported by Ozono (mothers: 15.0 ± 12.4, fathers: 16.0 ± 14.3), although it was lower than those reported in studies including patients in active treatment by Phipps et al. (mothers: 21.9 ± 17.9) and Kazak et al. (mothers: 43.6 ± 14.0, fathers: 32.6 ± 21.5), and in a childhood brain tumor survivor study reported by Bruce et al. (25.2 ± 20.75) [
32,
33,
34,
35]. Parental PTSS seems to decrease after treatment, but some parents continued to experience PTSS.
The present study included children aged as young as four to six years, whereas the Ozono study in Japan did not [
32]. In Japan, studies of emotional and behavioral functioning in preschool children with cancer and their parents have been rare, although a considerable number of children with cancer are preschoolers at diagnosis. More extensive evaluation of emotional and behavioral functioning in preschoolers with cancer and their parents is needed.
In our sample, the emotional and behavioral problems of children with cancer were associated with parental PTSS, but not by demographic or medical factors. To our knowledge, this is the first report of a study in Japan that revealed the relationships between the emotional and behavioral difficulties of children with cancer and parental PTSS, even after excluding the effects of potential confounders by multivariate analysis. There are few reports about psychosocial functioning of children with cancer and their parents in Japan compared to those in western countries. Particularly, very few reports have referred to the relationship between the psychosocial functioning of children with cancer and that of their parents, although Ozono has reported that PTSS in a child with cancer was correlated with that in his/her mother by bivariate analysis [
32]. Much previous research carried out in western countries revealed the correlation between the psychosocial functioning of children with cancer and that of their parents. Some previous research demonstrated that self-reported PTSS in the child with cancer and PTSS in their parents were significantly correlated [
35,
36]. Other studies also found that PTSS in both parents of childhood cancer survivors was associated with PTSS in those individuals [
37]. According to the theory of attachment, parents play a role as a secure base when their children face a traumatic event [
38]. Parents who suffer from PTSS are thought to have difficulty assuming this role [
39]. A previous longitudinal study, which revealed that initially high PTSS in mothers was related to poorer recovery from PTSS in their children, supports this suggestion [
40]. In order to improve emotional and behavioral difficulties of children with cancer, we must evaluate parental vulnerability to the development of PTSS and provide adequate intervention as needed.
The parents of children who received more intensive treatment had higher long-term uncertainty. Previous studies that excluded children with relatively severe cancer, such as brain tumor, failed to establish an association between objective medical factors and psychosocial functioning in either the children or their parents [
16,
17]. Recently, some studies that included patients with relatively severe cancer revealed that severely intensive treatment and late effects of treatment were associated with poor psychosocial outcomes [
41]. Therefore, we hypothesized that either the children who received more intensive treatment or their parents would develop more psychosocial difficulties. Our results indicated that these parents developed more psychosocial difficulties, whereas the children did not. These findings suggest that parents are at greater risk of being distressed by the experience of their children’s cancer than the children themselves. More studies that include children with relatively severe cancer are needed.
While the number of close friends was found to be significantly correlated with parental PTSS and emotional and behavioral functioning of the children by bivariate analyses, it did not exert a significant independent effect on the variance in the emotional and behavioral functioning of the children in the regression models. Friends are one of the most important social support resources for children [
15]. In addition, the number of close friends the child had may reflect the amount of social support of the parents as well, because parents often communicate with family members of the child’s close friends. Although social support is an important factor in preventing PTSS development after a traumatic event, previous studies on children with cancer did not conclude that social support improved the psychosocial functioning of the children or their parents [
15]. Our study suggested the possibility that the children’s close friends may support not only the children with cancer but also their parents. Children with cancer must be hospitalized for a long time. We may support these children and their parents by encouraging them to make an effort to continue to connect with their friends even during hospitalization. In addition, creating peer groups of children with cancer and their families may prevent development of PTSS.
By bivariate analysis, parents who informed their child of the disease had lower long-term uncertainty, but this was not significant in multivariate analysis. In both bivariate and multivariate analysis, there was no significant association between psychosocial functioning of the children with cancer and parent-child communication about the disease. We demonstrated that the child’s knowledge of their disease does not increase the parental burden or the child’s psychosocial difficulties, although in a 2003 survey, 43.5% of Japan’s pediatric oncologists thought the child’s knowledge of his/her cancer diagnosis would increase the parental burden [
19]. Our findings should encourage parents and physicians to try to inform children with cancer of their disease. Physicians must continue to support parent-child communication about the disease for a long time after treatment.
This study had several limitations. First, it was a one-time, cross-sectional survey, which cannot establish causal directionality. The second limitation is that we could not use randomization to categorize parents according to whether they informed the child of the disease. Parents who did not inform may have had psychosocial difficulties before the cancer diagnosis. The third limitation of this study is its small sample size. Establishing significant relationships between psychosocial functioning in the children and the various factors analyzed may have been impossible because the study was underpowered. The fourth limitation is that parental PTSS and CBCL were both reported by the parents of the child with cancer. We cannot deny the possibility that parents with more severe PTSS are more likely to report that their children have greater problems.