CHILDHOOD CANCER SURVIVORS NEED MONITORING

April 7, 2010 — Survivors of childhood cancer have a life expectancy up to 28% shorter than people in the general population and should be closely monitored for much longer than is usual, according to a new study reported in the April 6 issue of the Annals of Internal Medicine.

"These results suggest that recognition and treatment of illnesses associated with late effects in the first 35 years after therapy for childhood cancer will probably result in improved longevity," write the researchers, led by Jennifer M. Yeh, PhD, from the Harvard School of Public Health in Boston, Massachusetts.

Cumulative excess mortality was estimated using data from the Childhood Cancer Survivor Study, which comprised 5-year survivors, aged 15 years, who had been diagnosed with cancer at the age of 10 and who had been treated 20 to 40 years ago.

The model for this estimate considered 3 risk categories: that for the original cancer diagnosis; that for excess mortality from subsequent cancer and late effects (including cardiac, pulmonary, and external complications), and that related to age-specific mortality rates in the general population.

The analysis showed an average lifetime probability of 0.10 for late-recurrence mortality, of 0.15 for treatment-related death from subsequent cancer or from other complications, and of 0.05 for death from other causes.

Life expectancy for survivors was 50.6 years, which was 10.4 years shorter than for the general population. Reduced life expectancy varied by tumor type; it was 4.0 years for kidney cancer and 17.8 years for brain or bone cancer.

The authors note that "monitoring the health of current survivors and carefully evaluating therapies with known late toxicities in patients with newly diagnosed cancer are needed."

"Pretty Sobering Figure"

This study "reports a pretty sobering figure — an average of 10 years loss of life for long-term survivors. Previous studies have reported on late mortality and serious chronic health problems, but this is the first paper to estimate the loss of life and change in life expectancy," said Kevin C. Oeffinger, MD, director of the Adult Long-Term Follow-Up Program in the Departments of Pediatrics and Medicine at Memorial Sloan-Kettering Cancer Center in New York City.

Dr. Oeffinger was not involved in the study, and was asked by Medscape Oncology to comment on the findings.

The study authors point out that one limitation of their data is that treatment approaches have changed enormously in the past 20 years, and Dr. Oeffinger notes that radiation therapy now uses greatly reduced doses and volumes and different methods of delivery.

"However, while there have been some changes in chemotherapy, the agents (and doses) used today are pretty similar to those used in the era of the survivors in the Yeh et al study. We need further research to better understand who is at risk of preventable problems following contemporary therapy," Dr. Oeffinger said.

"Survivors of a childhood, adolescent, or young adult cancer should be followed periodically by a clinician familiar with their risks and screened according to the Children's Oncology Group recommendations," he added.

Childhood Cancer Success Story

The advances made in the treatment of childhood cancers has been one of the successes of the "war on cancer," according to an accompanying editorial by Patricia A. Ganz, MD, Jacqueline N. Cassillas, MD, and Anne Coscarelli, PhD, from the University of California, Los Angeles.

However, the 300,000 long-term childhood cancer survivors represent a new challenge, because most no longer receive care in a cancer-center environment, they write.

"Because childhood cancer survivors are very adaptable and used to denying difficulties — wanting to be 'normal' like their peers — they may minimize their symptoms and fail to get the attention of their internists, thus receiving less help than they actually need," they point out.

"Often the patient survivor is the sole repository of the cancer medical history, and no well-informed quarterback within the healthcare system is working with them to anticipate the potential late effects of treatment. Certainly health promotion, symptom management, specific attention to psychosocial needs, and surveillance for recurrence and specific late effects of treatment can help young adult survivors of childhood cancer maintain their health for as long as possible, and possibly improve the grim mortality statistics reported by Yeh and colleagues," they write.

Dr. Yeh and Dr. Oeffinger have disclosed no relevant financial relationships.

Ann Intern Med. 2010;152:409-417, 465-466. Abstract, Abstract