Childhood Cancer Survivors At Increased Risk Of Severe Health Problems As Adults

Huib N. Caron, M.D., Ph.D., of Emma Children's Hospital/Academic Medical Center, Amsterdam, presented the findings of the study at a JAMA media briefing in New York.

The introduction of more effective treatments for childhood cancer has dramatically improved survival rates, but this has been accompanied by the occurrence of late, treatment-related complications such as second cancers, organ dysfunction, and psychosocial and cognitive problems. Information is limited on the occurrence and risk of subsequent illnesses among adults who had cancer as children, according to background information in the article.

Dr. Caron and colleagues conducted a study to assess the total burden of adverse health outcomes (adverse events) following childhood cancer and evaluated treatment-related risk factors. The study included 1,362 five-year survivors of childhood cancer treated in a single institution in the Netherlands between 1966 and 1996. All survivors were invited to a clinic for medical assessment of adverse events. Medical follow-up was completed for 94.3 percent of survivors (median [midpoint] follow-up, 17.0 years). At the end of follow-up the median age of the survivors was 24.4 years, with 88 percent of survivors younger than 35 years.

The researchers found that of the 1,362 survivors, 19.8 percent had no adverse events, 74.5 percent had one or more events and 24.6 percent had five or more events. Additionally, 36.8 percent of the survivors had at least one severe or life-threatening or disabling disorder, and 3.2 percent died due to an adverse event. Almost 22 percent of adverse events were severe, life-threatening or disabling, or caused death. Of those events, orthopedic disorders occurred most often, followed by second tumors, obesity, fertility disorders, psychosocial or cognitive disorders, neurologic disorders and endocrine disorders.

Of all patients treated with radiotherapy only, 55 percent had a high or severe burden of events (defined as at least two severe events or one or more life-threatening or disabling event), compared with 15 percent of patients treated with chemotherapy only and 25 percent of patients who had surgery only. Survivors of bone tumors most often had a high or severe burden of events (64 percent), while survivors of leukemia or Wilms tumor (tumor of the kidney) least often had a high or severe burden of events (12 percent each).

"In conclusion, childhood cancer survivors are at increased risk of many severe health problems, resulting in a high burden of disease during young adulthood. This will inevitably affect the survivors' quality of life and also will ultimately reduce their life expectancy. Therefore, we feel that risk-stratified lifelong medical surveillance of childhood cancer survivors is needed to allow early detection of adverse events that are amenable to intervention. Future studies should focus on the efficacy of follow-up programs and other intervention strategies for adverse events, to further improve health outcomes in survivors of childhood cancer," the authors write.

Reference: JAMA. 2007;297:2705-2715.  

Editorial: Childhood Cancer Survivors, Late Effects, and a New Model for Understanding Survivorship

In an accompanying editorial, Kevin C. Oeffinger, M.D., of Memorial Sloan-Kettering Cancer Center, New York, and Leslie L. Robison, Ph.D., of St. Jude Children's Research Hospital, Memphis, Tenn., write that it is important for physicians to understand the possible subsequent health problems for childhood cancer survivors.

"... most primary care physicians, as well as surgeons, obstetricians, cardiologists, and other specialists, are not familiar with the health risks of this relatively heterogeneous population. Hence, as these survivors enter their young and mid-adult years, a period when their risk for many serious late effects is at its highest, they might not be screened for various late effects that may be modifiable or amenable to early diagnosis and treatment."

"It is critically important for physicians to recognize these risks, facilitate risk-based health care, and strive to improve therapy that not only improves cure rates but also reduces long-term morbidity."

Reference: JAMA. 2007;297:2762-2764.

Drs. Oeffinger and Robison report receiving grants from the National Institutes of Health.