Childhood cancer survivors at increased risk of renal failure
The Centers for Disease Control and Prevention (CDC) reports that over 20 million Americans aged 20 years or older suffer from chronic renal failure, and adult survivors of childhood cancers may be at an increased risk if they underwent certain chemotherapy or kidney surgery, according to a new study published in the journal Cancer Epidemiology, Biomarkers and Prevention.
Current research indicates that childhood cancer survivors treated with specific chemotherapy agents have impaired kidney function as a result, but whether their kidney function improves or gets worse over time has remained largely unknown.
Accordingly, researchers from the Netherlands conducted a study that analyzed 1,122 adult childhood cancer survivors aged 18 or over who visited the Late Effects of Childhood Cancer outpatient clinic at Emma Children's Hospital/Academic Medical Center between 1966 and 2003. All of the patients were then monitored over a period of 5 to 42 years after being diagnosed and treated for cancer.
For the study, the researchers looked at the after effects of several types of chemotherapy agents suspected of causing kidney damage over time, which include the following drugs:
• High-dose methotrexate
• High-dose cyclophosphamide.
The researchers also examined the kidney-damaging impact of radiation treatment to the kidney area, as well as the effects of a nephrectomy, which refers to the partial or complete surgical removal of the kidney.
All of the patients participating in the study underwent glomerular function testing and had their glomerular filtration rate (GFR) assessed to determine how functional their kidneys were.
As a result, the study concluded that childhood cancer survivors who were treated with ifosfamide or cisplatin during chemotherapy, as well as those who underwent a nephrectomy, had lower GFR and higher glomerular dysfunction. This continued throughout the follow-up period.
Moreover, the childhood cancer survivors treated with high doses of cisplastin also had the highest rate of kidney function deterioration.
As the study authors point out, these findings suggest that glomerular function deteriorated during the early years following cancer treatment and failed to recover. Given that glomerular function has been shown to continue deteriorating, the study authors therefore conclude that childhood cancer survivors may be at an increased risk for premature chronic kidney disease.
"We found that the kidney function of childhood cancer survivors treated with nephrotoxic therapy [treatments known to damage the kidneys] declines very soon after treatment and does not recover,” explained Renée Mulder, research associate of the Department of Pediatric Oncology at Emma Children's Hospital/Academic Medical Center.”
“Health care providers and survivors should be aware of the increased risk of early kidney damage after nephrotoxic treatment for childhood cancer, because these patients are also at increased risk for developing comorbidities, such as cardiovascular disease," Mulder added.
SOURCE: Cancer Epidemiology, Biomarkers and Prevention: Glomerular Function Time Trends in Long-Term Survivors of Childhood Cancer: A Longitudinal Study, September 24, 2013; doi: 10.1158/1055-9965.EPI-13-0036