- Pituitary gland = master gland
- Located at the base of the brain
- It balances hormones made by most glands
- Link between the brain and the endocrine system
- 80% of gland produces hormone
- Somatotropin or GH- Growth hormone
- Thyrotropin or TSH- Thyroid stimulating hormone
- Corticotrophin or ACTH- Adrenocorticotropic hormone
- Gonadotropins or FHS, LH- Follicle stimulating and luteinizing hormone
- 80% of gland produces hormone
- Nerve endings from hypothalamus
- Stores hormones made in hypothalamus
- Rare to have tumors form in posterior pituitary
- Pituitary adenomas are benign tumors
- Stay confined to the pituitary gland
- <1cm = Microadenoma
- >1cm =Macroadenoma
- 2x as common as micro
- Can grow and put pressure on nearby structures
- Pressure changes called mass effect
- Can crush pituitary cells
- Leads to decreased hormone production
- Can lead to many health problems
- Close to brain = nerve damage
- Changes in hormone production= systemic effects
- Functional pituitary adenomas
- Produce too much of a hormone
- Can produce more than one hormone
- Non-functional pituitary adenomas
- Also called null pituitary adenomas
- Doesn’t affect hormone regulation
- Often not removed unless they grow too large
- No environmental risk factors
- Family history
- Can be inherited but usually occurs independently
- Occurs more commonly in women
- Common in people 30-40 but can occur in any age
- Thought to occur in up to 20% of people
- Often unknown that a pituitary adenoma is present
- Incidentalomas- found on accident, usually on an MRI
- Local effect of mass
- Pressure on nearby structures
- Nerve damage
- Vision changes
- Nausea/ vomiting
- Change in behavior
- Change in smell
- Hypopituitary effects from crushing pituitary cells
- Low Growth hormone- decrease muscle/ bone growth
- Reduced muscle strength
- Increased obesity
- Decreased height and growth in children
- Low Gonadotropin- decreased sex hormone
- Men- low sex drive, impotence
- Women- low sex drive, breast atrophy
- Low Thyrotropin- slow down metabolism
- Cold intolerance
- Weight gain
- Low Growth hormone- decrease muscle/ bone growth
- Excess stimulating hormones from functional pituitary adenoma
- Producing excess hormone
- Prolactinoma- ↑ prolactin= decreased sex hormones
- Most common
- Same effects of low gonadotrophin
- ↑ GH- increased bone and muscle growth
- Increased size of hands and feet
- Bulky appearance but actually weak
- Glucose intolerance
- Giantism in children
D. Cushing disease- ↑ Corticotropin- excess cortisol
1. Central obesity
2. Moon face
A. Physical exam
A. Monitor for clinical manifestations
B. Hypophysectomy- Surgery to remove tumor
1. Transsphenoidal- Endoscopy
a. Through nose
b. Hole drilled beneath upper lip to access
2. Open craniotomy
a. Removed through small opening in skull
C. Stereotactic Radiosurgery
1. Destroyed from high doses radiation from multiple angles
D. Medication management
1. Some medications available that can actually ↓ the tumor size
a. Dopamine receptor agonists- slows down prolactin
b. Somatostatin analogue- slows down production of GH
- Hormone regulation
A. That’s what this is all about!
A. Growth can be accelerated or delayed.
A. Alteration in cellular production leads to tumor formation
- Hormone replacement therapy
- Sometimes required after surgery
- Followed closely by endocrinologist
- Dietary changes
- Specific diet recommendations with hormone imbalances
- Recommend dietitian
- Regular medical follow-up
- Tumors reoccur in 16% of patients
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All right. Hi guys. Today we are going to be talking about pituitary adenomas and how they affect the body. Okay. First, we’ll talk about a little A&P review, a brief review of the endocrine system here because the pituitary gland is the master gland in the endocrine system. It’s important to remember that it’s located here at the base of the brain, right underneath the hypothalamus, and it balances hormones made by most glands. That’s why it is the master gland. It’s the link between the brain and the endocrine system. So it’s receiving these messages from the hypothalamus, storing hormones for the hypothalamus, and then processing those and releasing these hormones to the rest of the body. It has the anterior and posterior sections. The anterior pituitary is 80% of the gland and the posterior pituitary is much smaller.
They pretty much always occur in the anterior pituitary. So that’s just important to mention. It does so much for the body. So take a deep breath with me and let’s dive into all the things that the pituitary gland does. So we talked about it receiving these messages and releasing the hormones that the hypothalamus makes. So we’ll go here first. It releases ADH to the kidneys to increase blood pressure, right? Save water pee less, and, oxytocin, related to growth, and reproduction. And then the anterior pituitary where most tumors form and these are the hormones that it releases. So thyroid-stimulating goes right to that thyroid gland to increase the production of T3 and T4, right? ACTH goes to the adrenals located on those kidneys to release cortisol, growth, hormone growth, and bones to make them grow right, prolactin- that works to release the LH and FSH, right? So these sex hormones, they’re affecting testes breasts, uterus, all these sex hormones, right? So those are, that’s a big function of the endocrine system and the pituitary gland. So what our pituitary adenomas? They are benign tumors, so they are not cancer.
It is very, very rare to have cancer on your pituitary gland. They’re almost always benign tumors or an adenoma An adenoma is always a benign tumor. So they like to stay confined to the pituitary gland. They can be micro or macroadenomas. If they’re micro, they’re less than one centimeter. If they’re macro, there’s greater than one centimeter. So as these ones start to grow, they can cause effects. They can cause health problems all on their own, just from a tumor growing in that space. And we’ll talk more about that later. They can be nonfunctional or functional. Functional just means that they are affecting hormones. They’re producing hormones. Non-functional, they’re not, and they can lead to many health problems. So we talked about local effects from the tumor itself and then also affects the endocrine system. So they can cause our hormones to go out of whack, which causes a whole slew of side effects.
Right? Okay. Etiology, there are no identified risk factors. So there’s not something modifiable you can do to prevent one of these from growing. It is linked to family history, but most often these do grow independently. Now, incidental is really interesting. They’re thinking that these occur in up to 20% of people, which is crazy, right? That’s a huge amount of people. A lot of people don’t even know they’re there. They usually happen between the age of 30-40 but can occur at any age, even children, but most, often 30 to 40 years old. And then I talked about a lot of times they’re there and we don’t even know, and those ones have a cool name of they’re called incidentalomas. So they are discovered on an MRI that’s done for some other reason. And they discover: Oh, you have a mass on your pituitary gland. Those are called incidentalomas and effects can be local. We talked about those. This is the mass effect from a tumor growing in a really teeny tiny spot, so they can be pressing or crushing nerves. We’re right next to the brain, right? There’s a lot of nerves around there, specifically the optic nerve. That’s what we see most. So that would be vision changes. So that would affect our vision or other local effects from a mass growing near our brain, which makes sense. Headaches, vomiting, nausea,or changes to smell. And even you can have a CSF leak that is rare, but think of where that is located, it’s right behind the nose, right? So these, these symptoms make sense.
And then in addition to crushing the nerves, they can also crush pituitary cells. So then the regular cells in our pituitary gland are not producing the way they should. And those are hypo pituitary effects. So we have low amount of hormones and the side effects that depend on what hormone we’re lacking. Right? So if we have low growth hormone, then we won’t be growing right. With GH, decreased bone growth decreased muscle growth. That makes sense, right? Also, decreased height if it’s in children. If we have low gonadotrophin, this leads to decreased sex hormones. Um, then we’re going to have decreased sex drive. So that’s decreased sex hormones, decreased sex drive, impotence breath, atrophy changes to the sex organs, right? Low thyroid hypothyroid, right? We have a lesson about this. So you can check that out on nursing.com, but it’s going to slow down our metabolism, right? Fatigue, cold, weight gain, all those that go with hypothyroidism.
And then also we can have symptoms that are more systemic from excessive release of hormones. So these typically produce one hormone too much. There are some adenomas that produce more than one hormone, but usually we see them producing one hormone way too much. So if it’s prolactin, it’s called a prolactinoma. This is actually the most common- prolactinomas increase in prolactin. And that equals a decrease in sex hormones. So just like we talked about the gonadotrophin and that same change in sex organs, sex drive, that sort of thing. If we have an increase in growth hormone, we’re going to be growing too much, right. Acromegaly. And that’s when our hands and feet grow. If our growth plates are closed, we’re not going to grow any taller, but other things are gonna grow bigger. Right? Bigger statue, that sort of thing. In children, they can get giantism. So people that are like seven feet tall, like crazy tall and that’s in children. Okay. And then what if we have the pituitary sending too many signals to the adrenals, we’re going to have an increase in cortisol. We know what that causes right? Cushing’s syndrome. So Cushing syndrome is caused by pituitary adenomas all the time. That’s a very common cause of Cushing syndrome. And we do have a lesson specifically about Cushing syndrome that you can review, but we’ll just talk about it briefly here. We have the central obesity, moon face, diabetes, acne. Absolutely. A very testable topic there. So just review that-Cushing syndrome. And these are obviously functional adenomas. They’re producing a hormone too much.
Okay- Treatment. And we’ll talk about diagnosis here too. So it’s diagnosed, we talked about MRI and also sometimes by CT, sometimes it’s found on accident. If that happens, sometimes we just monitor it. It’s not causing problems. We’re just going to keep watching it. And I can imagine those people are very nervous hearing that, that they’re not going to be treated for this tumor growing in their brain. There’s a risk-benefit ratio. Sometimes they do resolve on their own. But if they do need to remove it, there are different approaches. So we’ll just talk about where this is in the body, right? Our pituitary gland is about right there. So we can go transsphenoidal approach right through the nose and cut to the soft palette. And then we can use our scissors and snip that out of there. If that doesn’t work, we can remove it with a craniotomy. So drilling a hole right in through the skull to remove it. And then there’s also a way that we can use radiation radiosurgery. And that is going to shoot beams directly at the pituitary tumor to remove it. So those are the approaches to remove it. Or there is medication management, some medication can shrink tumors depending on what type of cells that it’s impacting. And also medication management is important because after we remove this pituitary gland, we can need hormone replacement. Often, almost, always. We just want to remove the tumor, right. But sometimes we move the other stuff too. So patient education, we need to talk about the importance of hormone replacement.
So they’re followed by an endocrinologist dietary changes, and this is related to hormone imbalances. So we’re talking about people with glucose-intolerance, that sort of thing. And then regular followup, because this can reoccur in up to 16% of patients. So we want to make sure they’re followed up.
Okay. Concepts- hormone regulation is huge, right? Not regular, sorry, regulation. That’s everything. That’s what we’re talking about. Right? We’re talking in the pituitary gland, the master gland. Cellular regulation. So something went wrong somewhere with apoptosis and cell development that caused the tumor to grow. That’s why we have the adenomas and then human development. This can be in kids with stunted growth or too much growth or adults, likewise, or also we’re talking about sex organ development. So some important concepts there. And then we’ll just review real briefly some key points. So the pituitary gland is a master gland. That’s why it makes so many effects if we have a tumor on it. Pituitary adenomas are non-cancerous. They can have an effect on hormone changes or a local effect from the mass growing. And that’s all I have for today. We love you guys, go out and be your best self, and as always happy nursing.