The experience of cancer and its treatment can be a daunting challenge for children and their families, leading to significant physical and psychological symptoms. Developing effective interventions that can ameliorate this unnecessary suffering is a critical priority for healthcare providers, researchers, and policymakers alike. However, the complexity of the symptom experience within pediatric and chronic illness contexts requires a multidimensional and holistic family-centered approach to designing effective interventions. In the realm of pediatric oncology symptom science, existing theories fall short of encompassing the comprehensive family-centered approach required to establish meaningful connections between theory, research, and practice. To pave the way for generating novel research questions, it becomes imperative to evolve current theories, specifically one that resonates with relevant knowledge in the field and anticipates the necessary advancements in science. In this editorial, we advocate for the adoption of a modified Theory of Unpleasant Symptoms (TOUS), an approach that holds promise in steering us toward unexplored avenues of research. By doing so, we can bring about a paradigm shift in the pursuit of improved outcomes for children suffering from cancer and their families.

The TOUS is a particularly relevant and useful theory that has been used to guide pediatric cancer symptom research. The TOUS describes the subjective experience of physical and psychological symptoms and emphasizes the importance of considering the level of intensity and distress caused by each symptom.1 The TOUS also recognizes that children’s symptoms may be influenced by their developmental stage, cultural background, and family dynamics. Therefore, healthcare providers must adopt a comprehensive approach that considers the unique needs and circumstances of each child and their family. One of the strengths of the TOUS is its emphasis on the subjective nature of symptoms, which is particularly important in the pediatric cancer population. It recognizes that symptom suffering can significantly disrupt developmental milestones and have a lasting impact on the child’s quality of life. In addition, the TOUS can be applied to understand the symptom experience across the life span, making it well-suited for use in pediatric oncology. Overall, the TOUS has expanded our understanding and measurement of the symptom experience for children with pediatric cancer. Its application has identified targets for novel symptom interventions, which can help healthcare providers to provide comprehensive and effective symptom management. The TOUS serves as a valuable tool for healthcare providers and researchers in their efforts to develop and test interventions that can alleviate the suffering of children with cancer and their families.

Researchers have noted the absence of the family voice as an important limitation in the context of pediatric cancer because caregivers often serve as proxy reporters for symptoms and health outcomes.2 To address this limitation and support targeted intervention development, we propose to contemporize the model, using a more holistic lens and with consideration of the current challenges in clinical care. To develop the next generation of symptom interventions, adaptations of the TOUS are required to integrate critical implicit assumptions grounded in practice that are prime for explicit inclusion to support a comprehensive family-centered framework. The aim of this editorial is to propose revisions to the TOUS to give us new foci that may help with explaining the complexity of the symptom experience and new targets for intervention to alleviate suffering and improve the quality of life for children with cancer and their families during this unimaginable time.

First, we propose the framework include the family voice, an assessment of the child’s symptoms from the perspectives of the child and caregiver, in addition to the clinician. Hinds et al3 identified the importance of the unique contribution and perspectives of patient, family, and clinician voices, for optimal symptom assessment. Yet, current symptom frameworks, including the TOUS, do not currently reflect the triad of voices. The intersection of the triad creates a symptom experience influenced by the phenomena of interdependence of these important individuals and creates an opportunity for concordance/discordance between two or more perspectives. Discordance is a well-documented occurrence when considering multi-informant data4–6; however, the clinical sequelae of divergent symptom reports in pediatric cancer are not yet well understood. Therefore, we propose the expansion of the TOUS to explicitly include these voices and acknowledge the relationships within the triad that may influence corresponding perspectives.

Next, we propose the addition of relationship factors and dyadic situational factors to be considered as new influencing factors. Relationship factors may include concepts important to understand unique dyadic or triadic relationships, such as communication, family functioning, or patient-clinician and family-clinician interactions. Given the potential of communication as a nonpharmacologic intervention target, further exploration of the dynamic nature of relationship factors throughout the cancer trajectory and the corresponding connection with symptom perspectives is warranted. In the context of new relationship factors, the framework should also distinguish the child symptom experience as interdependent on the relationship and perception of the primary caregiver and within a partial family context. Dyadic situational factors may be reflective of the dyad or family and not the individual child. Explicit inclusion of the dyadic relationship creates an opportunity to reframe existing situational factors of the TOUS and advocate for the addition of dyadic situational factors. In the context of pediatrics, many situational factors, such as social determinants of health, may be reflective of the dyad or family and not the individual child. For example, how does the financial toxicity experienced by a child’s primary caregiver influence the symptom experience of the child with cancer?

Finally, two other important elements should be considered, caregiver symptom experiences and time. Caregivers who care for a child with cancer experience their own distinct symptoms, such as stress, depression, and anxiety.7 Caregiver symptoms have been shown to be related to child symptoms8 and quality of life.9 A model that accounts for the symptoms of the caregiver may further reflect clinicians’ observations of the interrelationship between child and caregiver symptoms. Not least is the consideration of time. We propose the model explicitly acknowledges the trajectory of the cancer symptom experience, inclusive of relationship factors, and the evolution and change of the experience and influencing factors over time. Consideration of this variability should be reflected in both the model and intervention development.

This editorial proposes a holistic family-centered framework to bridge theory, research, and practice and advance symptom science in pediatric cancer. With these suggested holistic additions, the challenge now is whether the expanded TOUS can guide us toward both the development and testing of effective interventions that target the overlapping symptoms and relationship factors as reported by the dyad or triad. Fundamentally, this editorial is not intended to be decisive regarding modifications to the TOUS, but rather a thought-provoking impetus for further consideration and adaptation of a more holistic family-centered framework to generate new research questions. Further consideration and adaptation of this framework are warranted to guide future symptom science in pediatric cancer.

Sincerely,

Micah A. Skeens, PhD, RN, APRN, FAAN
Nationwide Children’s Hospital Research Institute and The Ohio State University, Columbus, OH
Kathleen E. Montgomery, PhD, RN, PCNS-BC
University of Wisconsin–Madison School of Nursing, Madison, WI

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