Are Pituitary Adenomas Genetic?
Pituitary tumours (pituitary adenomas) are surprisingly relatively common, estimated on post-mortem and radiological studies to occur in up to 20% of adults1.
Many non-functioning pituitary adenomas are small and if they don’t cause symptoms related to pituitary hormone disturbance or large size, often go unrecognised. Clinically relevant pituitary adenomas are considerably less common, occurring in approximately 1 in 1000 people2.
Most people diagnosed with pituitary adenomas, therefore don’t have any known family history of pituitary adenoma.
Over the past 10 years, the prevalence of underlying genetic mutations has become more apparent.
There are a number of recognised familial syndromes associated with pituitary adenomas. Around 5% of pituitary adenomas arise in the setting of a familial syndrome.2 Each familial syndrome is caused by a specific gene mutation and has particular patterns of hormone secretion and inheritance patterns. Table 1 below lists some of the more common familial syndromes, although there are more than 10 recognised familial tumour syndromes.
Genetic testing can be considered in select populations with pituitary adenomas. Those diagnosed at a young age have much higher likelihood of an underlying genetic cause of pituitary tumour. Those with a personal history of other conditions associated with pituitary tumours (table 1) or have a positive family history for pituitary adenoma or associated conditions could also be considered for genetic testing.
Genetic testing can be useful to confirm whether regular screening for other conditions associated with pituitary tumours is needed. It is also useful to guide appropriate screening for relevant family members. It is unlikely to change management of an individual’s pituitary condition.
There is no role for genetic testing in cases of craniopharyngioma or Rathke’s Cleft Cyst at present.
Your Endocrinologist will discuss in further detail if genetic testing is required in your individual case.
Table 1. Familial Pituitary Adenoma Syndromes
| Familial Syndrome | Gene | Functional Status | Frequency of Pituitary adenomas | Other associated conditions |
| Familial Isolated Pituitary Adenomas | AIP | Most commonly growth hormone secreting | 100% | Nil |
| Multiple Endocrine Neoplasia 1 | MEN1 | Most common Prolactin secreting or non-functioning | 40% | Hyperparathyroidism, Pancreatic or neuroendocrine tumours |
| Multiple Endocrine Neoplasia 4 | CDKN1B | Rare | As per MEN1 | |
| McCune-Albright | GNAS | Most common growth hormone secreting | ~20% | Polyostotic fibrodysplasia (bone disease), skin findings. |
Please contact the Pituitary Specialist Centre if you have further questions about Pituitary Adenomas.
References
- Ezzat S., Asa S.L., Couldwell W.T., Barr C.E., Dodge W.E., Vance M.L., McCutcheon I.E. The prevalence of pituitary adenomas: A systematic review. 2004;101:613–619. doi: 10.1002/cncr.20412.
https://acsjournals.onlinelibrary.wiley.com/doi/full/10.1002/cncr.20412 - Daly AF et al. High prevalence of pituitary adenomas: a cross-sectional study in the province of Liege, Belgium. J Clin Endocrinol Metab. 2006;91:4769–4775. https://academic-oup-com.ezproxy.library.uq.edu.au/jcem/article/91/12/4769/2656264
