Pituitary tumour
The anterior pituitary secretes a number of hormones including:
- Growth hormone (GH)
- Prolactin (PRL)
- Thyroid-stimulating hormone (TSH)
- Adrenocorticotropic hormone (ACTH)
- Melanocyte-stimulating hormone (MSH) (not produced in humans)[1]
- Follicle stimulating hormone (FSH)
- Luteinizing hormone (LH)
Tumours arising from such glandular tissue is known as an adenoma. As the pituitary is a highly glandular tissue the most common type of tumour seen is an adenoma, though other cell types are capable of tumourigenesis at this site also. Most pituitary tumours are benign though this may be somewhat of a misnomer. Whilst their malignant potential is negligible they may not be indolent and can cause symptoms. These symptoms may depend on if the adenoma is secretory or not and its potential for local growth.
As stated above the pituitary makes lots of hormones. Pituitary adenomas may secrete one or more (usually just one) of these in supraphysiologic amounts or they may be non-secretatory.
The most common tumours secrete growth hormone (see acromegaly) or prolactin (see prolactinoma or hyperprolactinaemia).
Thus phenotypical and physiological symptoms can be caused by these increases in hormones. Other symptoms can occur from local expansive growth of the tumour in the pituitary fossa. Classical symptoms include raised ICP and bilateral temporal hemianopia due to localised compression of the optic nerve.
Once tumours were categorised by their light microscopic appearance but now tumours are more reliably categorised by immunoperoxidase studies.
Blood tests for the hormones are important diagnostic tools.
CT scans, MRI and other imaging techniques are important for determining size (and seriousness of tumours), growth over time and treatment options.
Most tumours are benign but are quite serious because of their position close to important brain structures.
Treatment includes:
- Bromocriptine
- Surgical removal
- Ablation by radiotherapy
See also
References
- ↑ Brook, Charles. "Essential Endocrinology". 4th Ed. Blackwell Publishing, 2001, p. 38.