Named after neurosurgeon Dr. Harvey Cushing, Cushing's disease is a clinical syndrome that results from the overproduction of cortisol from the adrenal glands as driven by elevated secretion of a hormone ACTH from a pituitary adenoma.
Patients can develop diabetes and high blood pressure. They may have marked changes in their body shape, with weight gain in the abdominal area but wasting in the arms and legs, and increased weight visible in the face, and around the collarbone and scapulas. They have thin skin with easy bruising and new, wide, purple stretch marks.
The first line therapy for Cushing's disease is surgical removal of the pituitary adenoma, which offers a high success rate with an experienced surgeon. However, not all adenomas can be cured by surgery.
Current therapies for recurrent or residual Cushing's disease include:
- Adrenostatic Medications. These medications include ketoconazole and metyrapone. They stop cortisol production at the level of the adrenal gland but do not treat the pituitary adenoma per se.
- Radiosurgery. The use of CyberKnife® technology allows focus on the remaining tumor while minimizing exposure of nearby structures to the radiation
New therapies under investigation for Cushing's disease with potential to control the disease at the level of the pituitary adenoma are:
- Dopamine Agonists. There are publications showing that some pituitary adenomas which cause Cushing's disease have the dopamine receptor on their surface. These tumors may respond to these drugs to decrease ACTH secretion and even tumor size.
- New Somatostatin Analogues. Pituitary adenomas which cause Cushing's disease have specific somatostatin receptors which give hope for the promise of a new somatostatin analogue to shrink the tumor and decrease cortisol production.