73This lesion is seen almost twice as often in girls than boys; it can present at all ages, but usually is seen in children before they reach puberty. The incidence of these adenomas increases in pubescent and postpubescent individuals.8,24,66Some studies suggest that excessive release of ACTH can increase the risk in boys, but the older they get the less likely they will be to develop corticotropinoma.8,24SymptomsThe symptoms associated with Cushing syndrome include4: Obesity of the upper body.A rounded face.of cortisol.67Individuals who are depressed or who have malnutrition, alcoholism, or panic disorders also display elevated cortisol levels.4,12,32,66,68Cushing syndrome can be induced by long-term continued exposure to elevated levels of the cortisol hormone from excessive use of glucocorticoids, cortisol, or other corticosteroid medications. Medications such as prednisolone or prednisone often are used to treat conditions such as asthma, lupus, rheumatoid arthritis, or other inflammatory issues.4,69Cushing disease refers to Cushing syndrome that is caused by benign pituitary adenomas.70Although this distinction is important to note, literature surround-ing Cushing often refers to these conditions as Cushing syndrome. These pituitary lesions are much smaller than other pituitary adenomas and are responsible for the increased amounts of adrenocorticotropic hormone (ACTH).4,12,32,43In either the syndrome or the disease, the hypothalamus sends a corticotropin-releasing hormone to the pituitary gland, signaling the need to produce ACTH. ACTH causes the adrenal glands to produce cortisol and release the hormone into the cardiovascular system.4,50The hormone can be produced from ecto-pic sources (ie, outside the pituitary gland), but this is extremely rare. For example, small-cell lung cancer and bronchial carcinoid tumors can produce ACTH.71When this occurs, Cushing syndrome develops just as if the ACTH came from the pituitary gland.4,12,27,28,52,53Cushing syndrome was first described in 1932 by Dr Harvey Cushing, who identified 8 patients who exhib-ited the following similar signs52:Central body obesity.Glucose intolerance.Hypertension.Excessive hair growth.Osteoporosis.Kidney stones.Irregular menses.Emotional variation.Cushing syndrome more often affects individuals between the ages of 20 and 50 years.50It is estimated that for every million people, between 10 and 15 are affected annually.66 Cushing syndrome is 3 times more likely to affect women than men.12Pituitary adenomas result in 60% of cases of ACTH-dependent Cushing syn-drome. Research also has shown that only 5% of ACTH-
33RADIATION THERAPIST, Spring 2015, Volume 24, Number 1CEDirected ReadingRaye, Hadrych-RosierIndividuals with Cushing syndrome can experience other common symptoms, such as slow healing from infections, acne, cuts, or insect bites.
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