The study by Lund and colleagues discussed in this issue of The ASCO Post reinforces concerns about psychosocial health in long-term survivors of childhood cancer. Taking advantage of national registries, these investigators demonstrated that, when compared to the general population, survivors are at increased risk not only for emotional and behavioral disorders, but also for more pervasive and persistent neurodevelopmental and psychotic disorders. Siblings were also at increased risk for emotional disorders compared to the general population, particularly if they were born after the cancer was diagnosed.
Emotional and Behavioral Outcomes
Understandably, survivors of CNS tumors demonstrated higher risk for neurodevelopmental disorder and psychosis, suggesting a probable organic basis for these conditions. Survivors of hematologic cancers, CNS tumors, and solid tumors each demonstrated higher risk for emotional and behavioral disorders. Given the differential neurotoxic treatments associated with these cancer diagnoses, the relatively similar hazard ratios may suggest a more general impact from stress associated with the cancer experience. As such, these emotional and behavioral outcomes may be preventable.
Although the increased risk for mental health problems in long-term survivors is well demonstrated in this study, the number of problems identified is likely a significant underestimation of the true frequency of pathology. The frequency of contact for depression reported in this study range from 2.2% in survivors to 1.7% in siblings, both significantly lower than those reported by the World Health Organization or the National Institute of Mental Health in the United States, which report lifetime risk in the general population ranging from 3.3% to 21.4%.1,2 Similarly, frequency of anxiety in the current study is reported at 1.2% for survivors and 0.9% for siblings, though range from 4.8% to 31.0% in the general population surveys. These discrepancies may suggest that many survivors and siblings who experience mental health problems do not seek services from specialized treatment facilities or may go untreated.
Treatment-Specific Risks
Notably missing from this study is information on specific treatment exposures. Long-term follow-up guidelines have been developed based on studies demonstrating treatment-specific risk for physical and mental health outcomes.3 Such data were not available in the population registries employed by the investigators, though such information is vital for planning survivor-specific monitoring or interventions. Treatments differ within diagnoses and change over time, with the common variable often being type and cumulative dose of exposure. CNS tumors, for example, may be treated with surgery only or with high doses of cranial radiation therapy. It has repeatedly been demonstrated that dose and location of cranial radiation therapy is the driving force in increased risk for specific neurobehavioral and emotional health problems.4,5
Despite these shortcomings, the study by Lund and colleagues clearly demonstrates the need for monitoring mental health in long-term survivors of childhood cancer. Early identification and treatment of such conditions may improve long-term quality of life and support survivors as they continue to be productive members of our society. ■
Kevin R. Krull, PhD, is in the Department of Epidemiology and Cancer Control and the Department of Psychology, St. Jude Children’s Research Hospital, in Memphis,
Tennessee.
Disclosure: Dr. Krull reported no potential conflict of interest.
References
1. Kessler RC, Angermeyer M, Anthony JC, et al: Lifetime prevalence and age-of-onset distributions of mental disorders in the World Health Organization’s World Mental Health Survey Initiative. World Psychiatry 6:168-176, 2007.
2. National Institute of Mental Health: Mental Health Information, National Institutes of Health, 2013.
3. Landier W, Bhatia S, Eshelman DA, et al: Development of risk-based guidelines for pediatric cancer survivors: the Children’s Oncology Group Long-Term Follow-Up Guidelines from the Children’s Oncology Group Late Effects Committee and Nursing Discipline. J Clin Oncol 22:4979-4990, 2004.
4. Armstrong GT, Jain N, Liu W, et al: Region-specific radiotherapy and neuropsychological outcomes in adult survivors of childhood CNS malignancies. Neuro Oncol 12:1173-1186, 2010.
5. Brinkman TM, Zhu L, Zeltzer LK, et al: Longitudinal patterns of psychological distress in adult survivors of childhood cancer. Br J Cancer 109:1373-1381, 2013.
