A prospective study of hyperparathyroidism in individuals exposed to radiation in childhood
J. Cohen, T. C. Gierlowski and A. B. Schneider
Division of Endocrinology and Metabolism, Michael Reese Hospital and Medical Center, University of Illinois College of Medicine, Chicago 60616.
To determine the effects of childhood irradiation on the parathyroid
glands, a cohort of 4297 patients who received radiation to the tonsils
before the age of 16 years has been followed-up prospectively. Among the
2923 patients who were located and provided information, 32 patients
developed clinical hyperparathyroidism. The incidence of clinical
hyperparathyroidism was 18.7 per 100,000 person-years below the age of 40
years and 171 per 100,000 person-years in the age range of 40 to 60 years.
This represents a 2.9-fold (95% confidence interval, 1.6 to 4.3) and
2.5-fold (95% confidence interval, 1.1 to 3.9) increase in the incidence of
hyperparathyroidism compared with that among the general population. In
addition, 31% of the patients who developed hyperparathyroidism also
developed thyroid cancer, which is higher than the 11.2% prevalence of
thyroid cancer in the patients who received radiation therapy who did not
develop parathyroid tumors. Patients with a history of head and neck
irradiation should have their parathyroid glands evaluated on a regular
basis.
