Table 3.

Comparison of Findings in Persons with Isolated PitNETs by Family History and Presence/Absence of a Germline AIP Pathogenic Variant

CharacteristicsFamilial Isolated Pituitary Adenoma (FIPA)Simplex Somatotropinoma 1
AIP-FIPAX-LAGFIPA of unknown cause
Clinical features Typical age of onset (range) 2Adolescence (age 4-24 yrs)Early childhood (age <4 yrs; typically in first 2 yrs of life)40 yrs43 yrs
Average number of affected family members 33-4Usually simplex cases, but 3 families w/2-3 affected members have been described2-3NA
Male-to-female ratio 41:1 to 2:11:31:11:1
Adenoma features Somatotropinomas/somatomammotropinomas470%-80%~100%~50%NA
Size 4Macroadenomas in vast majorityUsually macroadenomas; less frequently, pituitary hyperplasia or a combination of PitNET & hyperplasiaMajority macroadenomasSmaller
Aggressiveness 4MoreVariableMoreLess
Response to standard treatment 4PoorerPoorerPoorerBetter

From: AIP Familial Isolated Pituitary Adenomas

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