Childhood cancer survivors who underwent radiation therapy should be screened regularly for growth disorders, pituitary hormone deficiencies and early puberty, according to a new clinical practice guideline issued by the Endocrine Society.
“Childhood cancer survivors have a high risk of developing endocrine disorders,” Charles A. Sklar, MD, a pediatric endocrinologist and director of the long-term follow-up program at Memorial Sloan Kettering Cancer Center in New York, said in a press release. “Our new guideline addresses the growing risk of endocrine disorders among childhood cancer survivors and suggests best practices for managing pituitary and growth disorders commonly found in this population. The guideline stresses the importance of lifelong screening of these survivors for earlier detection and optimal patient care.”
As Endocrine Today has previously reported, the rate of late-onset endocrine complications among childhood cancer survivors has risen as childhood cancer cure rates have substantially improved, with an estimated 50% of survivors experiencing complications ranging from thyroid dysfunction to obesity or type 2 diabetes during their lifetime, according to recent analyses. It is estimated that by 2020, there will be half a million childhood cancer survivors in the United States.
“Endocrine late effects are among the most commonly reported chronic conditions in childhood cancer survivors,” Wassim Chemaitilly, MD, of the division of endocrinology at St. Jude’s Children’s Research Hospital in Memphis, Tennessee, told Endocrine Today in an April 2017 interview. “It is estimated that one out of two survivors will be diagnosed with at least one endocrine or reproductive complication during her or his lifetime.”
Since 1975, the 5-year survival rate for children diagnosed with cancer before age 20 years increased from just more than 50% to more than 80% in 2014, according to data from the National Cancer Institute. However, these patients remain at increased risk for developing a broad range of health conditions, including endocrinopathies, that can appear years or even decades after the completion of cancer treatments.
The guideline includes several recommendations:
- Childhood cancer survivors exposed to cranial radiation therapy, craniospinal irradiation or total body irradiation at a young age or those with a history of inadequate weight gain should be monitored for impaired linear growth.
- Childhood cancer survivors treated for tumors in the hypothalamic-pituitary axis and those exposed to hypothalamic-pituitary axis radiation treatment should undergo lifelong, periodic clinical assessment for growth hormone deficiency. In children, height should be assessed every 6 to 12 months, according to the guideline.
- Childhood cancer survivors with a history of hydrocephalus or tumors developing in or near the hypothalamic region should be periodically assessed for central precocious puberty. Additionally, survivors exposed to hypothalamic-pituitary axis radiation at doses of at least 30 Gy should be screened for luteinizing hormone or follicle-stimulating hormone deficiency.
- Lifelong, annual screenings for thyroid-stimulating hormone deficiency and adrenocorticotropic hormone deficiency are recommended for childhood cancer survivors treated for tumors in the hypothalamic-pituitary axis region and in those exposed to at least 30 Gy hypothalamic-pituitary radiation.
To develop the guideline, an Endocrine Society-appointed guideline writing committee commissioned two systematic reviews. The first aimed to evaluate the effect of GH treatment in childhood cancer survivors on adult height, risk for type 2 diabetes, abnormal lipids, metabolic syndrome, quality of life, secondary tumors and disease recurrence. The second review aimed to determine the best screening and diagnostic tests for GH deficiency in childhood cancer survivors exposed to hypothalamic-pituitary radiation while noting a high variability in the confirmatory testing each study used.
The European Society of Endocrinology and the Pediatric Endocrine Society co-sponsored the guideline, which was endorsed by The Pituitary Society. The guideline was published online in The Journal of Clinical Endocrinology & Metabolism. – by Regina Schaffer
Disclosures: Sklar reports he has received conference honorarium from Sandoz. Please see the guideline for all other authors’ relevant financial disclosures.