Pituitary Tumors Flashcards
At what age can pituitary tumors occur?
Can occur at any age but mostly found in older adults
Which gender is more likely to develop pituitary tumors?
Women are more likely to develop these tumors than men
Which racial group is more likely to develop pituitary tumors?
More likely to develop in African Americans than in Caucasians
What are the known risk factors for pituitary tumors?
Very few known risk factors. There are no known environmental or lifestyle-related risk factors for pituitary tumors.
What is Multiple Endocrine Neoplasia MEN1?
A rare inherited disorder that affects the endocrine glands and can cause tumors in the parathyroid, pituitary glands, and the pancreas.
What effect do tumors from Multiple Endocrine Neoplasia MEN1 have on glands?
They cause the glands to secrete high levels of hormones.
What are other syndromes associated with pituitary tumors?
Multiple endocrine neoplasia MEN4, McCune-Albright syndrome, and Carney complex.
What is the most common manifestation of an expanding pituitary lesion?
The most common manifestation of an expanding pituitary lesion is headache and visual field defects.
What are gonadotropin secreting adenomas associated with?
Gonadotropin secreting adenomas can lead to gigantism in children and acromegaly in adults.
What condition is associated with ACTH secreting adenomas?
ACTH secreting adenomas are associated with Cushing’s syndrome.
What symptoms are caused by prolactin secreting adenomas?
Prolactin secreting adenomas can cause galactorrhea in females and impotence in males.
What condition is associated with thyroid stimulating secreting adenomas?
Thyroid stimulating secreting adenomas are associated with hyperthyroidism.
What is the principal imaging study for the pituitary gland?
CT or MRI.
Which imaging technique is superior for delineating the extent of tumor processes?
MRI is superior to CT.
What critical structures does MRI help to delineate relative to pituitary tumors?
Optic chiasm, vascular structures, cranial nerves, and cavernous sinuses.
What lab studies are used to confirm pituitary hormone dysfunction?
Blood and urine tests.
How do benign pituitary tumors typically spread?
Via local invasion.
Is there a true staging system for pituitary tumors?
No true staging exists; tumor size is used to classify.
How are pituitary tumors classified according to Hardy and Venzina?
Into 4 grades (0-4) based on the extent of expansion or erosion of the sella turcica.
What is the classification system for pituitary tumors primarily based on?
The presence of microadenomas (<1cm) and macroadenomas (>1cm) and the amount of tumor invasion.
What determines the treatment of pituitary adenomas?
Treatment depends on whether the adenoma produces excess hormones and which hormone it produces.
What are the two types of pituitary adenomas?
Functioning adenomas overproduce hormones, while non-functioning adenomas do not.
How are microadenomas treated?
Microadenomas are treated with surgery, specifically transsphenoidal surgery.
How are macroadenomas treated?
Macroadenomas are treated with surgery, specifically craniotomy.
What does transsphenoidal mean in the context of surgery?
Transsphenoidal means that the surgery is performed through the sphenoid sinus, a hollow space in the skull.
When is radiation therapy used for pituitary tumors?
Radiation therapy is used in patients who refuse surgery or are medically unfit for surgery.
What is the role of postoperative radiation therapy?
Postoperative radiation therapy is controversial but may reduce recurrence rates compared to surgery alone.
What modern techniques are used in radiation therapy for pituitary tumors?
Modern techniques include 3D conformal, SRS, and proton therapy, allowing focused delivery of the prescribed dose.
What is the position of the patient during the initial CT simulation for radiation therapy?
The patient’s neck is flexed with chin down toward the chest to minimize radiation exposure to the eyes.
What devices are used to fixate the position of the chin, mouth, and head during radiation therapy?
Bite blocks or intraoral stents are used.
What is the typical radiation dose for pituitary tumors?
The dose is 45-50 Gy at 1.8-2.0 Gy per fraction.
Larger mass may require a boost to 54 Gy.
What are the tolerance doses for organs at risk (OAR) in pituitary tumor treatment?
OAR TD 5/5: Optic Chiasm 50 Gy and Lens 10 Gy.
