title: Significant hypercortisolism during fractionated radiotherapy in a patient with a large corticotroph adenoma: a case report and literature review.
abstract: OBJECTIVE
  We describe a patient with a large, invasive corticotroph adenoma who developed severe hypercortisolism shortly after starting fractionated radiotherapy.
  
  
  METHODS
  We reviewed the patient's clinical course, along with relevant literature for similar reported cases.
  
  
  RESULTS
  A 29-year-old man was referred for radiotherapy for a residual and recurrent, invasive corticotroph adenoma. Prior to radiotherapy, he had a normal urine free cortisol (UFC) level of 44.7 μg/24 hours, with minimal symptoms. Within 2 weeks of radiotherapy, he developed hypertension, ankle edema, and hypokalemia (potassium level, 2.8 mEq/L), with a markedly elevated UFC level of 9,203 μg/24 hours. His UFC gradually decreased and normalized by the end of radiotherapy. One month later, the patient became adrenal insufficient, with a nondetectable 24-hour UFC. His adrenal function slowly recovered in 3 months. We are aware of only one previous case report of clinically significant hypercortisolism following radiotherapy in Cushing disease.
  
  
  CONCLUSIONS
  Radiotherapy may result in acute severe hypercortisolism in patients with a large corticotroph adenoma. This uncommon, but clinically significant, acute adverse effect of radiotherapy suggests that clinical observation and biochemical monitoring during or soon after radiotherapy may be indicated.
authors.affiliation: Department of Endocrinology, Diabetes, and Metabolism, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Soamsiri
authors.initials: S
authors.lastname: Niwattisaiwong
authors.affiliation: Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, Ohio Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Department of Neurosurgery and the Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: John H
authors.initials: JH
authors.lastname: Suh
authors.affiliation: Rose Ella Burkhardt Brain Tumor and Neuro-Oncology Center, Department of Neurosurgery and the Neurological Institute, Cleveland Clinic Foundation, Cleveland, Ohio Department of Neurosurgery, Geisinger Health System, Danville, Pennsylvania.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Weil
authors.affiliation: Department of Endocrinology, Diabetes, and Metabolism, Cleveland Clinic Foundation, Cleveland, Ohio.
authors.forename: Amir H
authors.initials: AH
authors.lastname: Hamrahian