Children and adolescents who have had a malignancy are at risk of medical, psychological, and social late effects of their disease and its treatment. If you're aware of potential problems and how to screen for them, you can help ensure the good health and proper development of these vulnerable youngsters.
Improvements in chemotherapy, radiation therapy, surgery, and supportive care have resulted in rewarding survival increases for infants, children, and adolescents who have had a diagnosis of cancer. It has been estimated that, in 2000, one in 900 young adults was a cancer survivor. In the year 2010, one in 250 young adults will be such a survivor, it is expected, with the prevalence of cancer survivors continuing to increase across all age groups.1
Many survivors have had to pay a cost for their cure, however, in the form of late effects, which may impinge on medical, cognitive, or psychosocial function. According to one study of long-term survivors, about 69% had at least one late effect, with 36% experiencing two or more.2 Among this group, 30% had a severe abnormality. Add to these data the fact that most childhood malignancies are diagnosed in young children, and it is clear that pediatricians can expect to care for more and more long-term cancer survivors.
Although definitions vary, a long-term survivor is generally considered a patient who has completed therapy at least two years earlier and has no evidence of active disease. In reality, patients are monitored, and may require treatment, for chronic effects of therapy sooner than two years after its conclusion. Many institutions have long-term survivor clinics. Although these clinics cannot and should not replace the pediatrician, we believe they are essential for providing complementary care and for facilitating referrals and educational assessments. Yet such clinics are in short supply, and many survivors do not have easy access to one.
Having cancer is devastating to the child and to the child's family. Any child who has had a malignancy is at risk for psychosocial sequelae, not only because of the extreme traumatic stress associated with a life-threatening illness but because the physical effects of therapy can potentially affect social functioning and relationships, academic success, and employment.3
Central nervous system effects of chemotherapy and radiation therapy are especially common among survivors of acute lymphoblastic leukemia (ALL) and of brain tumors. Neurocognitive late effects have an impact on academic and vocational achievement. These effects appear to be progressive, the result of insults that target executive functions and therefore become more apparent over time as the patient achieves higher educational levels. Fortunately, as treatments continue to improve and survival increases, more attention can be focused on decreasing late effects.
Monitor all patients for school difficulties. Keep track of their grades, especially any decline, and their consistency across subjects, as well as school and home behavior. Many recognized deficits may be the result of impaired processing speed, so whether it takes patients longer than peers to complete homework and whether they tend to have lower grades on tests than on assignments can indicate treatment-related learning problems. Survivors of ALL and brain tumors, as well as other patients treated with cranial radiation therapy or high-dose methotrexate or who experience academic difficulties, should be referred for formal neuropsychological testing. Be prepared to advocate for coverage of this testing, and be aware that patients may need periodic reevaluation. Psychoeducational evaluations, which are generally provided by the school, are not always adequate but may serve as a baseline.
Secondary, or treatment-related, malignancies remain one of the most potentially devastating effects of treatment for cancer during childhood and adolescence. Variables in their development are many and complex and include both treatment and patient-related characteristics. Being aware of when a patient is at particularly high risk for a secondary malignancy can result in appropriate counseling and monitoring essential for prevention, early diagnosis, and intervention.