Pituitary Incidentaloma

Pituitary Incidentaloma

A.Amouzegar

Endocrine Research Center,

Research Instutute for Endocrine sciences

Definition of pituitary incidentaloma:

pituitary lesion that is discovered on an imaging study

performed for an unrelated reason

By definition, the imaging study is not done for a symptom specifically related to the lesion, such as visual loss, or a clinical manifestation of hypopituitarism or hormone excess, but rather for the evaluation of symptoms such as headache, or other head or neck neurological or central nervous system complaints or head trauma

The evidence:

valid estimates of the pretest probability of an abnormal test of pituitary function could not be definitively determined because literature on this topic is sparse
Therefore, recommendations for the evaluation relied heavily on clinical experience
Data on the prevalence of hormone hypersecretion in pts with an incidentaloma are available from small observational studies (most retrospective) and estimated from autopsy data
Few data are available for or against a nonsurgical approach to management of asymptomatic pituitary incidentalomas

Etiology of pituitary incidentalomas:

In a series of sellar masses that required surgery, 91% were pituitary adenomas and about 9% were nonpituitary in origin, of which most were craniopharyngiomas and Rathke’s cleft cysts
1999 Differential diagnosis of sellar masses. Endocrinol Metab Clin North Am 28:81–117, vi
The 334 pituitary adenomas found the 3048 autopsy cases have been examined, finding
39.5% staining for PRL
13.8% staining for ACTH
7.2% staining for gonadotropins or a-subunits,
1.8% staining for GH
0.6% staining for TSH
3.0% staining for multiple hormones