Photo by Bill Branson
New research indicates that patients who undergo cranial radiotherapy (CRT) for pediatric cancer may have an increased risk of anterior pituitary deficits decades after they receive treatment.
The study also suggests these deficiencies often go undiagnosed, although they can impact health and quality of life.
These discoveries, reported in the Journal of Clinical Oncology, highlight the need for lifelong health screenings of pediatric cancer survivors, researchers say.
They studied 748 survivors of leukemia, brain, and other cancers, assessing the prevalence of and risk factors for growth hormone deficiency (GHD), luteinizing hormone/follicle-stimulating hormone deficiencies (LH/FSHD), thyroid-stimulating hormone deficiency (TSHD), and adrenocorticotropic hormone deficiency (ACTHD) after CRT.
The researchers observed survivors for a mean of 27.3 years (range, 10.8 to 47.7 years).
GHD was the most common deficiency, with an estimated point prevalence of 46.5%. The estimated point prevalence was 10.8% for LH/FSHD, 7.5% for TSHD, and 4% for ACTHD. The cumulative incidence of the deficiencies increased with follow-up.
Higher doses of CRT were associated with an increased risk of deficiencies. Doses of 22 to 29.9 Gy were significantly associated with GHD, doses of 22 Gy or higher were associated with LH/FSHD, and doses of 30 Gy or greater were associated with TSHD and ACTHD.
The researchers also found that male sex and obesity were significantly associated with LH/FSHD, and white race was significantly associated with LH/FSHD and TSHD.
GHD and LH/FSHD were the deficiencies that were most likely to be undiagnosed. GHD was not treated in 99.7% of affected survivors, and LH/FSHD was not treated in 78.5%.
There was an association between untreated GHD and reduced strength and muscle size, low energy, poor fitness, and abdominal obesity. Untreated LH/FSHD was associated with low bone mineral density, reduced fitness, high blood pressure, abdominal obesity, and elevated cholesterol and other blood lipids.
“This study provides much needed long-term follow-up data and shows that the risk of pituitary problems follows these survivors into adulthood,” said study author Wassim Chemaitilly, MD, of St Jude Children’s Research Center in Memphis, Tennessee.
“The findings also underscore the need for the nation’s growing population of childhood cancer survivors to get recommended health screenings, and the challenges they face in trying to navigate the healthcare system and follow that advice.”
Guidelines developed by the Children’s Oncology Group call for childhood cancer survivors treated with CRT to have their pituitary function checked annually. Dr Chemaitilly said the high percentage of survivors with previously undiagnosed hormone deficiencies in this study highlights the need for new strategies to ensure survivors receive recommended health checks.
He also said additional research is needed to help guide the management of adults with growth hormone deficiency. Treatment is expensive, and the long-term benefits in adults are uncertain.
