Nelson’s syndrome: a giant pituitary

Nelson’s syndrome is a pituitary mass that develops following total bilateral adrenalectomy (TBA) for the treatment of Cushing’s disease. It is one of the most challenging of all endocrine conditions. The frequent aggressiveness of the underlying ACTH-secreting pituitary adenoma (corticotrophinoma) necessitates regular biochemical and radiological screening. Failure to administer prophylactic neoadjuvant pituitary radiotherapy at the time of TBA and a rapid rise of ACTH levels during the first year following TBA are the main factors that may predict the occurrence of Nelson’s syndrome. Though, computerized tomography (CT) and magnetic resonance imaging (MRI) have led to the early diagnosis and improvement in management, these tumours are sometimes detected late, through clinical manifestations of invasion and compression of the surrounding structures. With this perspective in mind, we describe a 22-year-old gentleman who presented 10 years after TBA with right sided hemiparesis caused by a corticotroph adenoma.