Pituitary tumours are growths arising in the pituitary gland, a small endocrine gland located at the base of the brain. Most pituitary tumours are benign, but they can cause problems by producing excess hormones, reducing normal pituitary hormone production, or pressing on nearby structures such as the optic chiasm.
What Is a Pituitary Tumour?
The pituitary gland helps regulate several important hormonal systems, including the thyroid, adrenal glands, reproductive system and growth hormone axis. Pituitary tumours are commonly described as functioning when they produce excess hormones and non-functioning when they do not produce a clinically significant excess hormone.
Common Types of Pituitary Tumours
- Prolactinoma: produces excess prolactin and may cause menstrual disturbance, galactorrhea, infertility or low sex hormones.
- ACTH-producing adenoma: can cause Cushing disease through excess ACTH and cortisol.
- Growth-hormone-producing adenoma: can cause acromegaly.
- TSH-producing adenoma: can cause inappropriate TSH secretion and hyperthyroidism.
- Non-functioning pituitary adenoma: may be discovered incidentally or become symptomatic because of its size and pressure effects.
Prolactinomas are often treated initially with dopamine-agonist medicines, while treatment of other functioning or large symptomatic tumours may involve surgery, medicines, radiation therapy, or a combination depending on the diagnosis.
Symptoms of a Pituitary Tumour
Symptoms vary according to the type and size of the tumour. Hormone excess can produce symptoms specific to the hormone involved, while compression or loss of normal pituitary function can cause headaches, visual problems or symptoms of hypopituitarism.
- Headache
- Blurred or reduced peripheral vision
- Menstrual irregularity or infertility
- Milk discharge unrelated to breastfeeding
- Reduced libido or erectile dysfunction
- Unexplained changes in body composition or physical appearance
- Fatigue, low blood pressure or other features of hormone deficiency
A large tumour may press on the optic chiasm and cause visual field defects. This is one reason visual-field assessment can be important when a lesion is close to or compresses the optic pathways.
How Is a Pituitary Tumour Diagnosed?
Diagnosis generally combines clinical assessment, targeted hormone testing and pituitary MRI. The exact laboratory evaluation depends on the suspected tumour and may include prolactin, cortisol and ACTH assessment, IGF-1, thyroid function and reproductive hormones. MRI helps define the size and location of the lesion and its relationship to nearby structures.
If a pituitary incidentaloma is found, endocrine evaluation should assess both hormone excess and possible hypopituitarism. Visual-field testing is recommended when the lesion abuts the optic nerves or chiasm. Follow-up imaging and endocrine assessment depend on tumour size, symptoms and changes over time.
Pituitary Tumour Treatment
Treatment is individualized. Some small, asymptomatic lesions can be monitored. Prolactinomas commonly respond very well to dopamine-agonist therapy. Selected symptomatic or hormone-secreting adenomas may require transsphenoidal surgery, while radiation therapy is used in selected situations. The treatment plan depends on tumour type, hormone secretion, size, visual effects, response to medicines and overall clinical circumstances.
When Should You See an Endocrinologist?
An endocrinology evaluation is particularly useful when MRI shows a pituitary lesion, prolactin or another pituitary hormone is abnormal, periods or fertility are affected, there are symptoms suggesting cortisol or growth-hormone excess, or there are features of pituitary hormone deficiency.
At Vishuddha Endocrine Clinic in Ahmedabad, Dr. Moxit Shah, DM Endocrinology, evaluates Diabetes, Thyroid, Weight Loss and complex hormone disorders including pituitary conditions.
Related Endocrine Resources
Sources
- Endocrine Society – Pituitary Tumors
- Endocrine Society – Pituitary Incidentaloma Guideline
- NIDDK – Prolactinoma
- NIDDK – Acromegaly
This article is for general educational purposes and does not replace an individualized medical evaluation.
