Diagnosis:
Suggested by MRI and confirmed by pathology (brain biopsy/resection)
Clinical features:
- Non-secreting tumors: present with visual field defects commonly bitemporal hemianopsia. Also present with headaches or are incidentally found
- Hormonal syndromes with secreting tumors: amenorrhea and infertility with prolactinomas, acromegaly, Cushing’s disease with other hormones
- Pituitary apoplexy: Severe headache, Sudden visual loss or sudden collapse, multiple ocular nerve plasies
Findings on Investigations:
Microadenoma: <10 mm.
MRI T1, hypointense, doesn’t enhance unlike normal pituitary.
CT. hypodense, erosion of sellar floor, upward convexity of diaphragm sellae,
MacroAdenoma :
>1 cm. Hemorrhage may occur, may invade cavernous sinus, extend into suprasellar space (Michellin Man appearance)
MRI:
- T1, hypointense lesion, if present hypointense cysts
- T2, if present hyperintense cysts
Pathology:
Histology:
Small round blue cells. Further classification based on other stains & immunohistochemistry.
Hormonal tests:
Raised prolactin: Prolactinoma or compression of the stalk. In prolactinoma, Prolactin >200 ng/ml
Insulin stimulation tests: hypopituitarism
OGTT with GH +clinical features: acromegaly
TSH secreting pituitary adenoma: high TSH, high free T4, high free T3. TRH sitimulation test: flat TSH response
Treatment:
Depends on presence & absence of hormonal secretion & neurological deficits
If nonsecreting:
- Surgery:
- Transfrontal or trasphenoidal approach, or subfrontal craniotomy if there is intracranial extension beyond the pituitary fossa
- If +Hypohpysectomy: need hormonal & steroid replacement
Radiation therapy