1. Metastatic medullary thyroid carcinoma presenting as ectopic Cushing’s syndrome
- Author
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Tom Moran, Austin G. Duffy, Maria M. Byrne, Hannah E Forde, Niamh Mehigan-Farrelly, Megan Greally, and Katie Ryan
- Subjects
Adult ,Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Urology ,030209 endocrinology & metabolism ,White ,April ,Vandetanib ,Diseases of the endocrine glands. Clinical endocrinology ,Thyroid carcinoma ,03 medical and health sciences ,Otolaryngology ,0302 clinical medicine ,Internal Medicine ,medicine ,Thyroid ,Hyperparathyroidism ,Metyrapone ,business.industry ,Neck dissection ,RC648-665 ,medicine.disease ,Unique/Unexpected Symptoms or Presentations of a Disease ,medicine.anatomical_structure ,Oncology ,Calcitonin ,030220 oncology & carcinogenesis ,Dexamethasone suppression test ,business ,Ireland ,medicine.drug - Abstract
Summary A 41-year-old male presented to the Emergency Department with a 6-month history of back and hip pain. Skeletal survey revealed bilateral pubic rami fractures and MRI of the spine demonstrated multiple thoracic and lumbar fractures. Secondary work up for osteoporosis was undertaken. There was no evidence of hyperparathyroidism and the patient was vitamin D replete. Testosterone (T) was low at 1.7 nmol/L (8.6–29.0) and gonadotrophins were undetectable. The patient failed a 1 mg dexamethasone suppression test (DST) with a morning cortisol of 570 nmol/L ( Learning points Unexplained osteoporosis requires thorough investigation and the workup for secondary causes is not complete without excluding glucocorticoid excess. MTC should be considered when searching for sources of ectopic ACTH secretion. Resistance to tyrosine kinase inhibitors is well described with MTC and clinicians should have a low threshold for screening for recurrent disease.
- Published
- 2021