What are the types of pituitary tumors?
Pituitary tumors can be benign or malignant. Benign pituitary tumors are called pituitary adenomas. Malignant pituitary tumors are called pituitary carcinomas – or pituitary cancers.
Almost all pituitary tumors are pituitary adenomas. Only rarely do they become cancerous.
Pituitary adenomas are classified by size and whether they are functioning (secrete hormones) or non-functioning (do not secrete hormones). Most pituitary adenomas are functioning.
The types of functioning pituitary adenomas are:
- Prolactin-secreting adenomas. These are the most common type of pituitary tumor. Excess prolactin can lead to menstruation or fertility problems in women and impotence in men. Women who are not pregnant or breastfeeding could also produce breast milk.
- Adrenocorticotropic hormone-secreting (ACTH-secreting) adenomas. These tumors make ACTH, which causes an overproduction of cortisol and leads to Cushing’s disease.
- Growth hormone-secreting adenomas. These tumors produce growth hormone, which leads to joint pain and enlarged facial features, hands and feet.
- Thyroid-stimulating hormone-secreting (TSH-secreting) adenomas. The production of too much TSH causes hypothyroidism.
- Gonadotropin-secreting adenomas. These tumors secrete follicle-stimulating hormone and/or luteinizing hormone, leading to menstrual problems in women and low testosterone levels in men. They are very rare.