Prevalence and severity of chronic diseases in adult survivors of childhood cancer: A report from the Childhood Cancer Survivor Study

English

Reviewer: Ryan Smith , MD
Abramson Cancer Center of the University of Pennsylvania
Ultima Vez Modificado: 17 de mayo del 2005

Presenter: K.C. Oeffinger
Presenter's Affiliation: University of Texas Southwestern Medical Center
Type of Session: Plenary

Background

The cure rate of childhood cancers is now >78%
Currently, 1 out of every 640 people age 18-45 are childhood cancer survivors
The effects of the cancer itself or the toxic treatment needed for cure can have lost lasting effects
This study was performed to determine the cumulative incidence of chronic diseases, compare them to matched (sibling) control groups, and determine the highest risk patients

Materials and Methods

A total of 10,397 patients were nvolved in the study. Included patients were diagnosed from 1970-1986, were <21 years old at diagnosis, and survived their cancer >5 years
The matched control group consisted of 3034 siblings to the cancer patients
A severity score, using the 3^rd version of the common terminology criteria for adverse events questionnaire was done. This was designed to detect chrnic illnesses and give them a severity score of 1-5
Grade 1-mild, Grade 2-moderate, Grade 3-severe, Grade 4-life threatening or disabling, Grade 5-death
Examples of these grades were given: Grade 3-pulmonary fibrosis, cirrhosis, CHF, gonadal dysfunction; Grade 4-second malignancy, MI, CVA, organ transplant, paralysis with daily limitations, cognitive dysfunction

Results

In the cancer survivor group, 46% were female, 84% were white, and median age at survey was 27
67% were treated with chemotherapy, and 62% had received radiation
Despite excluding scarring and disfigurement, 77% of the survivors had a chronic condition by the scoring system. 66% had a grade 1 or 2 condition and 38% had a grade 3-5
Grades 1-2 conditions were fairly similar among the survivors and the control group, but the control groups had many less severe conditions
Relative risk of any grade in the survivors was 1.9 and for grade 3-4 conditions, it was 4.2
The relative risk of grade 3-4 conditions in patients receiving radiation was 3.3, and in those receiving chemotherapy, it was 2.9
Factors associated with highest risk included being treated with an anthracycline or alkylator (4.9 RR), chest/abdominal/pelvic radiation (RR6.9), abdominal/pelvic radiation with an alkylator (RR 7.0), chest radiation and and alkylator (RR 7.2)

Author's Conclusions

Even excluding scarring and disfigurement, the vast majority of childhood cancer survivors have at least one chronic condition, with 33% with a grade 3-5 condition
The group of cancer survivors were 4.2 times more likely to have a chronic condition compared to their siblings
Chest radiation and alkylators were associated with the highest risk of chronic disease

Clinical/Scientific Implications
This study documents what pediatric oncologists have thought for years-that survivors of childhood cancers have long-reaching implications in the form of chronic problems. This was even more substantiated by comparing the cancer survivors to matched controls in the form of their siblings. This is even without considering scarring and disfigurement, which is extremely common in these patients. Also consistent with common opinion, patients who received both radiation and chemotherapy had a higher incidence of chronic conditions. Though this may simply mean that patients with more advanced disease have higher complications, the effect of treatment cannot be discounted. What may be most interesting about this study is that chemotherapy had just as high of a risk of developing chronic problems than did radiation. Radiation has long been associated with long term problems, yet it seems that chemotherapy is just as toxic, most likely in the form of neuropathies, asthenias, and leukemias. It appears that radiationis not alone in causing cancer survivors long term problems.