Childhood cancer survivors who have been exposed to therapies that cause pulmonary dysfunction are associated with more restrictive defects and diffusion abnormalities, according to a study published online first in the Journal of Clinical Oncology.
Researchers led by Saro Armenian, DO, MPH, of the City of Hope National Medical Center examined childhood cancer survivors who had undergone baseline pulmonary function tests followed by comprehensive evaluation after a median of five years.
They were compared with age- and sex-matched healthy controls upon the secondary evaluation. The median age of subjects at cancer diagnosis was 16.5 years, and median time from diagnosis to secondary evaluation was 17.1 years.
The researchers found that, compared to the healthy control group, the survivor group faced a 6.5-fold increased risk of restrictive defects, as well as a 5.2-fold increased risk of diffusion abnormalities.
An age younger than 16 years at diagnosis and exposure to more than 20 Gy chest radiation was also associated with restrictive defects.
Female survivors who were treated with more than 20 Gy chest radiation were shown to have a decline in diffusion function over time.
“Diffusion capacity declines with time after exposure to pulmonary-toxic therapy, particularly among females and survivors treated with high-dose chest radiation,” the authors concluded. “These individuals could benefit from subsequent monitoring.”