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RADT317 - Brain > Pituitary Tumours > Flashcards

Pituitary Tumours Flashcards

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1
Q

How common are pituitary tumours?

A

Relatively common

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2
Q

What percentage of CNS tumours are pituitary tumours?

A

10-15%

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3
Q

Where do most pituitary tumours arise?

A

Anterior lobe

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4
Q

Histologically what are all primary tumours?

A

Benign adenoma

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5
Q

Why can Pituitary tumours be dangerous?

A

Dangerous due to their location e.g.
they can compress the optic chiasma and cause visual disturbances or blindness

May extend into cavernous sinus
local pressure symptoms

Clinical syndromes associated with abnormal hormone production

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6
Q

What is the Cavernous sinus?

A

A large channel of venous blood creating a “sinus” cavity bordered by the sphenoid bone and the temporal bone of the skull. The cavernous sinus is an important structure because of its location and its contents which include the third cranial (oculomotor) nerve, the fourth cranial (trochlear) nerve, parts 1 (the ophthalmic nerve) and 2 (the maxillary nerve) of the fifth cranial (trigeminal) nerve, and the sixth cranial (abducens) nerve.
PRL secreting adenoma - hypogonadism+Galactorrhoea

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7
Q

Classified by WHO (2017) what are pituitary tumour cell types?

A

Corticotrophs
Somatotrophs
Lactotrophs
Thyrotrophs
Gonadotrophs

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8
Q

What were Pituitary tumours classed as in the past?

A

Acidophilic, eosinophilic, basophilic

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9
Q

What is the most common Pituitary Adenoma?

A

Lactotrophs are the commonest

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10
Q

Lactotrophs

A

Secrete prolactin and some may also secrete growth hormone (GH)

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11
Q

Gonadotrophs

A

30% are non-secreting macroadenomas, these most recently are referred to as “whispering” gonadotrophs) some – secrete luteinising hormone (LH), follicle stimulating hormone (FSH) and thyroid stimulating hormone(TSH)

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12
Q

Corticotrophs

A

10-15% of cases – secrete adrenocorticotrophic hormone (ACTH)

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13
Q

Somatotrophs

A

Secrete growth hormone (GH)

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14
Q

Thyroid lesions

A

Extremely rare (secrete TSH)

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15
Q

Posterior Pituitary

A

Tumours are occasionally seen called pituicytomas

Generally arise from glial cells

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16
Q

Pituitary Adenoma Tumour Effects

A

Headache

Visual impairment (blindness, bitemporal hemianopia, tunnel vision
homonymous hemianopia)

Thirst and increased appetite

Loss of recent memory

Partial or complete hypopituitarism

Partial or complete hyperpituitarism

17
Q

What is Hypopituitarism?

A

Rare condition

Pituitary secretes inadequate amounts of one or more of its hormones

Can be progressive, eventually under secreting all pituitary hormones

18
Q

What does Hypopituitarism cause in children?

A

Failure to grow
Failure of pubertal development

19
Q

What does Hypopituitarism cause in adults?

A

Malaise, pale “waxen doll” complexion, intolerance to cold, amenorrhoea, loss of libido, impotence, loss of secondary sexual hair distribution, acute abdominal pain (hypopituitary crisis) and low blood sugar

20
Q

Who are Craniopharyngioma tumours most common in?

A

Most often diagnosed in children, teenagers and young adults.

21
Q

Where do Craniopharyngioma tumours occur?

A

Tend to grow near the base of the brain, just above the pituitary gland. Craniopharyngiomas do not usually spread, but they occur close to important structures in the brain and can cause problems as they grow. They can cause changes in hormone levels and problems with eyesight. Children with craniopharyngioma can have weight gain and growth problems.

22
Q

ACROMEGALY hyperactivity – excessive growth hormone production.

A

Adults over 20-25
Occasionally runs in families

23
Q

Acromegaly signs and symptoms

A

Enlarged hands and feet

Coarsened, enlarged facial features

Coarse, oily, thickened skin

Excessive sweating and body odour
Small outgrowths of skin tissue (skin tags)

Fatigue and muscle weakness

A deepened, husky voice due to enlarged vocal cords and sinuses

Severe snoring due to obstruction of the upper airway

Impaired vision

Headaches

Enlarged tongue

Pain and limited joint mobility

Menstrual cycle irregularities in women

Erectile dysfunction in men

Enlarged liver, heart, kidneys, spleen and other organs

Increased chest size (barrel chest)

24
Q

What is Macroadenoma?

A

Excess growth hormone

25
Q

What is Gigantism?

A

In children whose pituitary produces excess growth hormone the condition is known as gigantism

26
Q

Cushing’s Syndrome Corticotrphic adenoma secreting excessive ACTH

A

Weight gain

Sleep disorders

Raised blood pressure

(easy) bruising

Moon face

Thin, vulnerable skin

Psychological changes

Blurred vision

Osteoporosis

Irregular or absent menstrual cycles

Excessive hair growth

Muscular weakness

Impaired wound healing

Fatigue

27
Q

Pituitary Diagnosis and Investigations

A

History

CT

MRI

Lateral skull x-ray

Assay of anterior pituitary hormones

28
Q

Pituitary Adenoma Aims of Treatment

A

Reverse neurological impairment

Stem tumour recurrence

Replace hormones

Normalize levels of elevated hormones

29
Q

Pituitary Adenoma Management

A

Tumours < 1 cm in diameter (microadenomas; contained within Pituitary fossa) - suitable for trans-sphenoidal resection

Large prolactinomas (macroadenomas) - craniotomy – Transfrontal surgery alone is not adequate due to the high rate of recurrence Postoperative radiotherapy is recommended

Dopamine agonists – Bromocriptine/Cabergoline

Sythetic somatostatin analogues – Octeroide/Somatostatin

30
Q

Pituitary Adenoma post-operative radiotherapy

A

External beam RT

Stereotactic radiotherapy

Yttrium 90 or Gold 198 implantation

Proton beam therapy

Daily recommended tumour tumour dose 1.8 Gy delivered over 5 weeks
There is some evidence that in order to avoid recurrence this dose must be exceeded
45 Gy / 25 # / 5 weeks

31
Q

Pituitary Adenoma Early Sequelae

A

Erythema
Epilation
Headache

6 years post radiotherapy pituitary function may be poor
Hormone replacement therapy (HRT) is required eg corticosteroids, thyroxin and testosterone

32
Q

Pituitary Adenoma HRT

A

All patients will require treatment which will have to be individually designed

Diabetes insipidus DDAVP injection/nasal spray /oral

Men – testosterone replacement therapy

Women – cyclical oestrogen and progesterone (the pill)

FSH and LH to sustain fertility

Children need aggressive GH therapy (adults don’t require GH)

Thyroxin

The HRT must imitate normal hormone levels

33
Q
A

RADT317 - Brain (10 decks)

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