Pituitary Microadenoma

A young man comes into the ER with vision changes.  He has no other symptoms but is very frightened by these sudden changes!.  After a stat CT head the Radiologist reveals that this young man has a pituitary microadenoma.  A pituitary microadenoma is a tumor less than 10 mm in diameter.  These adenomas are capable of secreting hormones or being clinically inactive.  If this leasion is discovered while investigating other problems they are called incidentalomas.  This tumor usually originates from a local mutation with loss of function of the genes controlling self proliferation.  According to studies the United States has a 10% prevalence of pituitary leasions, and internationally an 11% prevelence.  Microadenomas are not usually terminal but do put pressure onto to the optic chiasma; which can cause vision loss.  These adenomas can occur at any age but do tend to occur in the aging population. 

There are several different types of microademonas.  If it is an incidentalomas there is usually no other symptoms and most times theses tumors are found in those who are seeking treatment for another condition such as headache.  Prolactinomas may also be asymptomatic as long as the prolactin levels are not very elevated.  In women these tumors can cause galactorrhea, amenorrhea, or infertility.  In men this can cause hypogonadism, erectile dysfunction, and decreased libido.  ACTH -secreting adenomas can cause Cushings Disease, Growth Hormone-Secreting adenomas cause acromegly, TSH-Secreting hormones are rare but will cause hypothyroidism. 

Treatment for adenomas can range from medication to surgery to diet change.  For prolactinomas, dopaminerginic drugs are given.  For other tumors, especially those resulting in Cushnings and agromegaly, surgical removal is advised.  Radiation therapy may also be indicated.  Overall most microadenomas are too small to cause any problems and most are incidental findings but each case should be treated carefully and no assumptions should be made in regards to how an individual will react to treatment.