October 11, 2006 – Cancer in children is now cured in many cases, but the treatment can have lasting deleterious effects on health. A huge study of childhood cancer survivors shows that almost two thirds have at least 1 chronic condition resulting from the treatment, and almost a quarter have 3 or more.
These latest results from the Childhood Cancer Survivor Study (CCSS), headed by Ken Oeffinger, MD, from the Memorial Sloan-Kettering Cancer Center, in New York, appear in the October 12 issue of the New England Journal of Medicine. The chronic conditions suffered by survivors included second cancers, cardiovascular disease, renal dysfunction, severe musculoskeletal problems, and endocrinopathies.
The findings "confirm the extraordinarily high incidence of late, and often permanent, complications arising from intensive treatment with combination chemotherapy and ionizing radiation," comments an accompanying editorial. "They also demonstrate that the risks are cumulative, with no evidence of a plateau so far."
As nowadays more than 75% of children with cancer can be cured of their disease, it "would seem to be incumbent on us to ensure that survivors of childhood cancer are followed closely by physicians who understand the effects and outcomes of cancer treatment," writes the editorialist, Philip Rosoff, MD, associate professor of pediatric hematology-oncology at Duke University, in Durham, North Carolina.
However, who exactly should be monitoring these survivors is unclear. "In actual fact, very few people have the expertise to take care of them, for a variety of reasons," Dr. Rossoff commented to Medscape. Historically, these patients are cared for by pediatric oncologists, who know about the late effects of treatment, but as these patients grow older, they drift away from the specialty clinic, and "and adult oncologists don't know about this stuff," Dr. Rossoff commented. "I think the best approach would be to disseminate more information about these patients and their problems to general pediatricians, internists, and family doctors, who can then work collaboratively with specialists giving them high-quality (and knowledgeable) care."
"Remarkable Long-term Study"
The CCSS is a "remarkable long-term study, which does for the survival of childhood cancer what the Framingham Heart Study did for the natural history of cardiovascular disease," the editorial comments. Although there have been other reports, no other study "has approached the sheer number of patients in the cohort followed by the CCSS."
This latest report details findings from 10,397 survivors and 3034 siblings.
The survivors had a mean age of 26.6 years (range, 18 – 48 years), and the mean time from the diagnosis of their cancer was 17.5 years (range, 6 – 31 years). Data were collected on patient questionnaires, and all conditions were self-reported without verification, except for second cancers and death, the researchers comment.
The study found that among the 10,397 survivors:
62.3% reported having at least 1 chronic condition.
37.6% had at least 2 chronic conditions.
23.8% had 3 or more chronic conditions.
27.5% had a condition that was severe or life threatening.
Compared with the siblings, the survivors were 3 times more likely to have a chronic health problem and 8 times more likely to have a condition that was severe or life threatening (eg, myocardial infarction, congestive heart failure, premature gonadal failure, second cancers, and severe cognitive dysfunction).
The study was restricted to children who had the following cancers: leukemia, central nervous system (CNS) tumor, Hodgkin's disease, non-Hodgkin'slymphoma, Wilms (kidney) tumor, neuroblastoma, soft-tissue sarcoma, or bone tumor. Of these, 3 groups were at highest risk – the survivors of bone tumors (who are likely to have severe limitations in activity, even if spared amputation), those with CNS tumors (who are likely to have significant cognitive impairment), and those with Hodgkin's disease (who have the highest risk of second cancer and heart disease).
Some of the treatments were associated with a 10-fold increased risk (or more) of developing severe or life-threatening conditions. These included: chest radiation plus bleomycin or an anthracycline; chest radiation plus abdominal or pelvic radiation; an anthracycline plus an alkylating agent; and abdominal or pelvic irradiation plus an alkylating agent.
However, all the patients in this study were treated for cancer before 1986, and treatment has evolved since then. The approach to many childhood cancers has changed considerably in recent years, with escalating intensity of treatment paralleling an improvement in survival rates, the editorial comments. Hence, patients treated more recently would be expected to have a different, but analogous, array of long-term complications, it adds.
Surveillance of Childhood Cancer Survivors
Surveillance is of key importance, the editorial says, and should be carried out by doctors who know both what these patients have been through and what kinds of complications to look for in the future.
"Sadly, such follow-up is the exception rather than the rule," Dr. Rosoff writes. The sort of complications that develop in these survivors "can demand a level of knowledge that is beyond the range of the general internist or family doctor or even of medical oncologists."
In fact, new doctors may refuse to accept such a patient into a practice because of the history of cancer treatment, Dr. Rossoff told Medscape. Alternatively, doctors who do accept such a patient then find that they don't know how to deal with these late complications. The best approach is for a new doctor to contact the original oncologist and establish a collaborative treating relationship, he said.
One problem is that childhood cancer survivors rarely have their medical notes flagged to alert all health professionals dealing with them as to their history, and "they should," Dr. Rossoff commented to Medscape. There have been many suggestions from various groups (including the Children's Oncology Group) that the patients themselves should be provided with a portable, concise summary of their medical/oncology history, including specifics about treatment. "However, in the United States, in the absence of a truly computerized and portable medical record system, this can be less than ideal, as these things can easily be lost."
N Engl J Med. 2006;355:1572-1582, 1522-1523.
Medscape Medical News © 2006 Medscape
Cite this: Zosia Chustecka. Childhood Cancer Often Cured, but Damage From Treatment Persists for Years - Medscape - Oct 11, 2006.