A study by Wilson et al investigating the impact of radiation therapy on adult survivors of pediatric abdominal and pelvic tumors has found that these survivors were significantly more likely to have insulin resistance, high levels of triglycerides, and low levels of high-density lipoproteins compared with the general population. Interventions targeting body composition may facilitate the management of cardiovascular disease risk in this population, according to the study authors, who published their findings in Cancer Epidemiology, Biomarkers & Prevention.
Although improvements in the treatment of childhood cancers have resulted in 5-year survival rates of more than 80% for pediatric patients, these survivors are at increased risk for developing abnormalities in body composition—including obesity, dyslipidemias, and insulin resistance—later in life. Body composition abnormalities and cardiometabolic impairments are particularly concerning because they can result in the development of life-threatening diseases, including atherosclerosis, coronary artery disease, myocardial infarction, stroke, and type 2 diabetes.
Study Methodology
Participants in this study included 431 adult survivors of pediatric abdominal or pelvic solid tumors who had been previously treated at St. Jude Children’s Research Hospital. Their median age during the study was 29.9 years. The most frequent childhood diagnoses were neuroblastoma, Wilms tumor, and germ cell tumor. The median age of the participants at diagnosis was 3.6 years. Approximately 37% and 36% of the participants had received abdominal and pelvic radiation therapy, respectively, as part of their treatment.
The researchers assessed the relative lean mass and fat mass of the participants using dual x-ray absorptiometry. Metabolic outcomes, including insulin resistance, high-density lipoprotein, low-density lipoprotein, and triglycerides, were based on laboratory values and medication usage. General linear regression was used to evaluate associations between treatment and lifestyle with body composition; binomial regression was used to evaluate associations between body composition and metabolic outcomes and physical performance.
To assess the impact of radiation therapy, the researchers compared the participants’ body composition, metabolic abnormalities, and physical function to those in the general population, using age-, sex-, and ethnicity-matched data from the 2013–2014 National Health and Nutrition Examination Survey (NHANES).
KEY POINTS
- Adult survivors of childhood abdominal and pelvic solid tumors who had been treated with radiation therapy were significantly more likely to have insulin resistance, high levels of triglycerides, and low levels of high-density lipoproteins compared with the general population.
- Interventions targeting body composition may facilitate management of cardiovascular disease risk in this population.
- Further research is needed to assess whether interventions in both childhood and adulthood could remediate abnormalities in body composition and cardiometabolic impairments due to radiotherapy.
Study Results
The researchers found that compared with data from NHANES, the participants in the study were significantly more likely to have insulin resistance (33.8% vs 40.6%) high triglycerides (10.02% vs 18.4%), and low levels of high-density lipoproteins (28.9% vs 33.5%). There were no significant differences in the levels of low-density lipoproteins between the survivors and the general population.
The researchers’ analysis also showed that survivors of abdominal and pelvic solid tumors had lower relative lean body mass than the general population, and that the lower relative body mass was associated with the dose of prior abdominal or pelvic radiation. There was no significant difference in relative fat body mass between the survivors and the general population; however, the survivors who had high relative fat mass had reduced quadriceps strength at 60°/second (P < .001) and 300°/second (P < .001), and reduced distance covered in the 6-minute walk (P < .01).
“Abdominal/pelvic radiotherapy is associated with body composition changes that can adversely influence metabolic outcomes and performance status among survivors…. Interventions targeting body composition may facilitate management of cardiovascular disease risk in this population,” concluded the study authors.
Potential Interventions
“While it may not be possible to avoid radiation therapy as a key treatment for many solid tumors, early research suggests that resistance training interventions in survivors increases lean mass,” said Carmen L. Wilson, PhD, assistant member in the Epidemiology and Cancer Control Department at St. Jude Children’s Research Hospital and lead author of this study, in a statement. “Further work is needed to see if training would also impact cardiometabolic impairments in this population.”
Disclosure: For full disclosures of the study authors, visit cebp.aacrjournals.org.
