Familial isolated pituitary adenoma: review of four families

S. Belo; J. Mesquita; C. Nogueira; A. Magalhaes; M. Basto; J. Pereira; D. Carvalho

Introduction: Pituitary adenomas are frequent brain tumors, with prevalence of about 1:1000. Most occur sporadically. The familial forms represent 5% of cases. These can be found associated with other endocrine neoplasia (MEN 1, Carney complex, MEN 4) or as a clinical isolated entity – FIPA. This is characterized by the presence of pituitary tumors in two or more family members, in the absence of features of other endocrine syndromes. AIP gene mutation, which may or may not be present, has been linked to FIPA. A review of four FIPA families was made. The Table 1 summarizes their main characteristics.

Conclusion: FIPA are characterized by the predominance of prolactinomas and somatotrophynomas (GH; 75%). They can be divided into families of homogeneous phenotype (only one tumor type, ex. isolated familial somatotrophynomas (IFS)) or heterogeneous (all types can occur, including non-functioning, but as a rule, at least one prolactinoma or GH producing tumor). This is a heterogeneous entity in which virtually all phenotypic combinations are possible. FIPA patients, especially with AIP gene mutation (positive in 15% of the heterogeneous phenotype and 50% of the IFS), are younger, have larger, more aggressive and resistant to therapy tumors.

**Table 1**
Family	Number studied	Number affected	Family link	Age of diagnosis	Gender	Tumor type	Therapy	AIP
1	8	2	Siblings	40	♀	ACTH, PRL	Surgery	NG
			46	♀	PRL	Bromocriptine	NP
2	18	2	Siblings	31	♀	PRL	Bromocriptine	NP
			34	♂	PRL	Bromocriptine	NP
3	24	2	Mother and daughter	28	♀	GH, PRL	Surgery, RT	NP
			63	♀	NFA	Surveillance	NP
4	16	2	Siblings	38	♂	NFA	Surgery	NP
			43	♀	PRL	Bromocriptine	NP
♀, female; ♂, male; PRL, prolactin; NFA, non-functioning pituitary adenoma; NG, negative; ND, non-determined; RT, radiotherapy.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.

Endocrine Abstracts

P1363