Diagnosis of pituitary disease

Signalling pathways and transcription factors involved in the development of the pituitary gland continue to be identified. Mutations in the genes encoding these factors have been shown to lead to pituitary tumours and hypopituitarism. Pituitary adenomas are relatively uncommon and slow growing. The onset of symptoms and signs is often insidious, particularly with non-functioning adenomas, so patients tend to present late and there is often a delay in diagnosis. A high index of suspicion is therefore essential. Tumours may present: with symptoms/signs of hormonal overproduction; with the effects of large tumour size and destruction/pressure on normal pituitary tissue and surrounding structures which may lead to hypopituitarism; following acute haemorrhage/infarction of large macroadenoma (pituitary apoplexy); OR increasingly identified with the widespread use of diagnostic imaging for other reasons (pituitary ‘incidentalomas’). MRI (coronal and sagittal planes) is the imaging modality of choice for pituitary lesions. It allows clear definition of the pituitary lesion, its margins and involvement of the optic chiasm and surrounding structures. CT scan is an alternative in patients with pacemakers, metallic clips or other metallic foreign bodies. Care of patients with pituitary tumours is increasingly being delivered through a multidisciplinary team approach to streamline care and decision-making.