Hyperparathyroidism after irradiation for childhood malignancy.

PURPOSE: To examine the occurrence of hyperparathyroidism in a cohort of patients undergoing combined parathyroid and thyroid surgery after previous head-and-neck irradiation for childhood malignancy. METHODS AND MATERIALS: This is a retrospective cohort study for the years 1996 to 2007. The study group comprised patients undergoing surgery in the University of Sydney Endocrine Surgical Unit who had received previous head-and-neck irradiation in childhood and who were identified as having pathologic thyroid and parathyroid characteristics. RESULTS: A total of 53 patients were identified in whom head-and-neck irradiation for the treatment of childhood malignancy had been documented. In each of the cases, thyroid disease was the primary reason for referral for surgery. Five of these patients (10%) were found to exhibit coexisting hyperparathyroidism. The latency period for hyperparathyroidism was less than 20 years in 4 of the 5 cases. There were four conventional parathyroid adenomas and one parathyroid lipoadenoma. All patients exhibited a significant decrease in postoperative calcium levels after surgery. CONCLUSIONS: To our knowledge, this is the first study to document the significant risk of hyperparathyroidism after radiation exposure for childhood malignancy. The timeframe for development of disease is much shorter than that published for individuals who have undergone irradiation for benign diseases. High doses of therapeutic radiation at a young age make childhood survivors of malignancy at especially high risk for developing hyperparathyroidism.

Breakthrough pain in children with cancer.

The aims of this prospective study were to determine the prevalence, characteristics, and impact of breakthrough pain in children with cancer. Twenty-seven pediatric inpatients with cancer (aged 7-18 years) who had severe pain requiring treatment with opioids and who received care in the Oncology Unit at the Children's Hospital at Westmead, Sydney, Australia participated in this study. The children responded to a structured interview (Breakthrough Pain Questionnaire for Children), designed to characterize breakthrough pain in children. Measures of pain, anxiety, and depressed mood were completed. Fifty-seven percent of the children experienced one or more episodes of breakthrough pain during the preceding 24 hours, each episode lasting seconds to minutes, occurring 3-4 times/d, and most commonly characterized as "sharp" and "shooting" by the children. Younger children (7-12 years) had a significantly higher risk of experiencing breakthrough pain compared to teenagers. No statistical difference could be shown between children with and without breakthrough pain in regard to anxiety and depression. The most effective treatment of an episode of breakthrough pain was a patient-controlled analgesia opioid bolus dose. Further studies of breakthrough pain in children and more effective treatment strategies in this age group are necessary.