Pituitary Tumours – Symptoms and Treatments

Pituitary Tumours

Many types of tumours can occur in the pituitary gland. The most common tumours in the pituitary gland are pituitary adenomas (which are benign). However, metastatic cancer can dwell in the pituitary gland when the cancer cells metastasize to the pituitary gland.

• Benign pituitary adenomas can be divided into nonfunctioning tumours and functioning tumours depending on the capability of tumour cells to produce hormones. Nonfunctioning pituitary adenomas do not produce active hormones by themselves.
• Nonfunctioning tumours mechanically compress surrounding structures such as the normal pituitary gland and optic system.
• Functioning pituitary adenomas produce a hormone(s) in excess.
  • Excess amounts of hormone produced by tumour cells cause symptoms dependent on the type of hormone.
  • Functioning pituitary adenomas include prolactinomas (PRL overproduction), adenomas that cause Cushing’s disease (ACTH overproduction), adenomas that cause gigantism or acromegaly (GH overproduction), and TSH-producing tumours.

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• Prolactinomas are the most common functioning pituitary adenomas and produce an excess amount of prolactin that results in amenorrhea (irregular menstrual periods), breast discharge (galactorrhea), infertility and sexual dysfunction.
• Pituitary adenomas that produce ACTH cause Cushing’s disease.
  • Symptoms of Cushing’s disease include ruddy moon face, truncal obesity, buffalo hump, hypertension, abdominal striae, easy disability, depression, psychosis, irregular menses, impotence, osteoporosis, muscle weakness, etc. Cushing’s disease is a serious condition requiring prompt treatment.
• Pituitary adenomas that produce growth hormone cause gigantism in children (due to still active growth plates) or acromegaly in adults.
  • In acromegaly, the jaw, cheeks, fingers and toes are thickened along with the enlargement of soft tissues such as the tongue, nose, and lips. Affected adult patients might find that their shoes or hats do not fit properly any longer.
• TSH-producing adenomas, which are relatively rare, cause goitres (enlarged thyroid gland) and thyroid hyperfunction disorders.

Symptoms Of Pituitary Tumours

• Symptoms of pituitary tumours are:
  • Hormonal disorders from excessive production of hormones from tumours.
  • Pituitary hormonal dysfunction from compression of the normal pituitary tissue.
  • Visual disorders from tumour compression of the optic system.
  • Other symptoms related to the compression of the surrounding brain such as the
    hypothalamus.
• When functioning pituitary adenomas produce hormones, the excess amount of hormone will cause particular hormonal disorder symptoms depending on the type of hormone as described earlier.
• When pituitary adenomas become large, they compress and make the normal pituitary gland tissue hypo- or nonfunctional (hypopituitarism) resulting in pituitary hormonal dysfunction. Most often, nonfunctioning adenomas grow to large sizes undetected and result in hypopituitarism.
• However, functioning adenomas can also cause general hypopituitarism even while producing an excess amount of a particular hormone.
• When pituitary tumours compress the optic system (which is located just above the pituitary gland), visual disorders may develop. The most common visual disorder is a visual field defect at the outside view of each eye known as bitemporal hemianopsia.
• Other symptoms such as memory disorder, hydrocephalus and other brain dysfunctions can develop if the tumour is large enough to compress the hypothalamus.
• Pituitary adenomas are known to bleed spontaneously (pituitary apoplexy).
• When spontaneous bleeding occurs inside a pituitary adenoma, symptoms of severe headaches, visual disorders, eye movement disorder and altered consciousness can develop. Immediate medical treatment is necessary and surgical treatment is often required.

Treatments Of Pituitary Tumours

• Medical, surgical, and/or radiation treatments are available for pituitary tumours. Prolactinomas can be treated with medications (bromocriptine is most commonly used). Surgical treatment is indicated when medication side effects or intolerance develops.
• Acromegaly can be treated with octreotide medication but does not respond as well as prolactinomas do with bromocriptine.
  • Often, acromegaly requires surgical removal of the tumour. If surgery is not successful, octreotide medication or radiation treatment (gamma knife surgery) can be considered.
• Cushing’s disease requires surgical removal of the tumour as the first line of treatment. If surgical treatments fail to relieve symptoms, radiosurgery or medical treatment can be instituted.
• TSH-secreting adenomas require surgical treatment. When nonfunctioning tumours cause symptoms, surgical treatment is the first choice among the treatments.
  • If surgical treatment is not successful, radiation treatment (conventional radiation or radiosurgery) has to be considered.
• Conventional transsphenoidal surgery is performed under the operating microscope via an incision underneath the upper lip (sublabial incision) or intranasal incision (transfixional incision). It requires two to three days of nasal packing and three to five days of hospital stay.
• A new surgical technique that utilizes an endoscope instead of the traditional operating microscope has been used nowadays.
  • Endoscopic pituitary tumour surgery is performed through a nostril without conventional incisions. After surgery, nasal packing is not required.
• Postoperative discomfort is minimal.
  • Often, the hospital stay is overnight. Endoscopic surgery does not require the use of a metallic trans-sphenoidal retractor that is used for conventional microscopic surgery.
  • A 4-mm endoscope is placed in front of the tumour in the sphenoidal sinus and the tumour is removed with specially designed surgical tools.