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I am gyms for a topless and we're going to be talking about multiple endocrine
neoplasia
today we're talking about MEN 1 We have no significant disclosures to make.
MEN 1 is also called Wermer syndrome
people like to remember the 3 P's because these patients have pituitary,
parathyroid, and pancreatic lesions
as Dean Wormer used to say "The Doctors are now on
double secret probation" and we'll talk more about that later on
in addition to having the three Ps these patients also have cutaneous lesions
angifibroma, collagenoma, as well as lipoma
they may have adrenal cortical disease including hyper pleasure as well as cortical adenoma
they may get abdominal carcinoid but they may also get bronchial
and thymic carcinoid and they may have Zollinger
Ellison syndrome from a gastrin secreting carcinoid tumor
Lastly, they may develop other CNS neoplasms including meningioma and ependymoma
Looking first at the skin - the classic lesion that we see in these patients
is the angiofibroma. This also occurs in tuberous sclerosis but they are far less
numerous when they are seen in patients who have the men1
they may also get cutaneous call at enormous
if we think about the goals for imaging we want to
focus on the pituitary for the head the parathyroid in the neck
and we want to focus on looking for carcinoid tumors in the abdomen
and in the chest. Pituitary imaging -
about two-thirds of patients will have a pituitary adenoma and 2/3 of them will be
symptomatic
it may be the first sign ofhis disease in up to twenty five percent of patients.
The overall prevalence of pituitary disease is 15 to 60%
of MEN 1 patients
Patients with men1 tend to be younger and have larger tumors
that are more invasive as compared to sporadic pituitary adenoma.
had enormous they may have multiple lesions they may also have hyperplasia
about two-thirds up the pituitary adenomas in men1 are going to be microadenoma
- smaller than 10 mm
most of these are going to be hormonally functional and most of those
that are functional will be producing prolactin which may
cause
amenorrhea and galactorrhea. About 10 percent we'll have growth hormone
secretion with gigantism and/or acromegaly
and only about five percent (or perhaps a little bit more)
will have Cushing's disease because of ACTH secretion
In up to forty percent of the patients multiple hormones be produced
Remember the pituitary gland is about the size of a dime in is located at the
top of the clivus.
Pituitary adenomas usually occur in adult patients
they are divided into macro-adenomas that are larger than ten millimeters and
these typically present with visual symptoms from compression of the optic chiasm.
These patients may have the classic "tunnel vision" or bitemporal hemianopsia.
Pituitary microadenomas, by definition, are less than 10 millimetres and fit
entirely within the normal sized pituitary fossa
These patients will present because of endocrine symptomatology.
most commonly because of a prolactin secreting tumor but any of the hormones
can cause an
endocrine clinical presentation. The primary questions are whether the
patient has a macroadenoma and if so is there involvement of the cavernous sinus.
Because prolactin secreting tumors are treated medically - with dopamine agonists -
localizing them may be less critical.
In contrast, there is high significance in localizing the ACTH secretint corticotroph adenomas
which must be identified for the neurosurgeon to remove
although there are several different techniques for imaging microadneomas, the thin slice 3D techniques
GRE or SPGR, post contrast, appear to be the most sensitive.
If we look at this case, the initial MRI was read as negative - in retrospect
there is a small lesion visible after changing the image contrast.
However, on the 3D SPGR image,
we can see very clearly an area of
decreased enhancement located on the left side the pituitary gland.
Typically pituitary adenomas enhance a little bit more slowly than
the normal pituitary gland.
This can be helpful in identifying them with dynamic scans. Microadenomas are
going to enlarge a portion of the gland they may cause deviation
up the pituitary talk to one side. However, this is no longer considered a reliable sign.
They may cause upward convexity of the gland and they may cause erosion or remodeling
of the sellar floor. This patient has an ACTH secreting
microadenoma.
On the routine imaging it's very difficult to identify but we can see
that the stalk is deviated towards the right side,
and the left side of the floor appears to be deviated downward.
So, we think that the adenoma is located here in the left-hand portion of the gland.
However, in the same patient, when we do
the SPGR image, we can now identify that the actual location of the lesion
is on the right side of the gland.
So in this particular patient these classic features are paradoxical and are
actually incorrect in localizing the pituitary microadenoma.
When we do parathyroid imaging we want to differentiate between
localized adenomas and hyper hyperplasia.
there are multiple parathyroid glands - and any one of them, or multiple glands -
may have a parathyroid adenoma
Hyperplasia may involve
enlargement of multiple parathyroid glands; and, we also have to make sure
that we look for a ectopic locations of the glands.
The most recent parathyroid scan guidelines, from 2012, from the Society of
Nuclear Medicine
show that the common indication is an elevated parathormone level in association
with an elevated calcium.
There are two primary methods that can be used for scanning
99m technecium sestamibi or tetrofosmin will
localize in both the thyroid and the parathyroid glands.
However, sestamibi will washout from the thyroid faster;
and, dual (time) phase imaging may show a difference - which is going to be
the parathyroid
adenoma. Some institutions do dual
isotope subtraction imaging using two different
radiopharmaceutical ligands: either sestamibi or tetrofosmin;
and, 99Tc pertechnetate - which localizes
only in the thyroid gland. If you subtract thepertechnetate image
from the combined image, then what is left should only be parathyroid activity.
by be an enormous so normally the pair the
Bayreuth picks up to protect me take and the
Bayreuth and the parathyroid pick up the system a B&B to TRUE FALSE min
But, if we subtract the normal thyroid tissue signal, then the only thing that is left
with the activity is going to be the parathyroid glands - and that might be
the parathyroid adenoma.
If we look at this case, we first have the composite image (pertechnetate and sestamibi).
We then made a normalization here for the technetium intensity.
and then, when we subtracted technician from the MIBI,
we can see the location here of the parathyroid
adenoma. We must be very careful to look in the mediastinum for ectopic parathyroid glands. In this patient, on the CT, there is a
soft tissue mass anterior to the arch of the aorta.
The second CT shows enhancement - it is been stained with contrast material - renographin 76 was given
angiographically
and achieved a chemical ablation of this adenoma
When we think about imaging the gut and pancreas, we are looking for the carcinoid or
islet cell tumors. These are APUD tumors - or Amine Precursor Uptake and Decarboxylate
APUD tumors can be sporadic, or manifestations of MEN 1 or von Hippel-Lindau
disease.
they can be functional or non-functional; and, a variety of hormones may be
produced by these gastroduodenal or
pancreatic neuroendocrine tumors.
Zollinger-Ellison syndrome may be associated with MEN1
The vast majority of patients who have gastrin secreting tumors have peptic
ulcer disease.
However, only a very small minority - less than one percent - of
all patients with peptic ulcer disease actually have a gastrinomas.
The majority of gastrin secreting tumors are sporadic but up to a quarter
are going to occur in MEN 1 patients; and, serum gastrin levels can be measured.
The majority of gastrin secreting tumors (with or without MEN) are located in what is called
the "gastrinoma triangle".
Some patients may have multiple
gastrin secreting tumors.
The sensitivity by CT and MR is related to tumor size, and is low. Endoscopic ultrasound combined with nuclear medicine
octreotide scaning has high sensitivity - approaching is ninety percent.
MR only has a sensitivity of about 50 percent.
So we want to remember to look carefully in the "gastrinoma triangle".
So what is the gastronomic triangle or the carcinoid "Delta"?
Well, this is where ships, planes, and surgeons may disappear ... ;)
The triangle is marked by the junction of the common hepatic and cystic ducts,
the junction at the neck and body the pancreas, and the junction of the second
and third portions of the duodenum.
So we have in the diagram an outline of the gallbladder. We can see the cystic duct
and the common a bile duct coming together. We have the pancreas here; and,
we have duodenum. These three landmarks form a triangular shape. Here this is the
gastronomic triangle or the gastronomic Delta.
As Dean Wormer warned us about earlier in the discussion.
In this particular patient we can see in this en bloc resection
that there are multiple pancreatic neuroendocrine tumors (NETs)
as well as one in the wall the duodenum. This is fairly typical for patients
that have the MEN1 syndrome. Surgeons usually palpate the duodenal wall looking for additional lesions.
MEN1 syndromes with gastrin secreting tumors are going to be associated with
mucosal hypertrophy and
rugal fold thicking of the stomach; and, we want to be very careful to identify
all the lesions that these patients may have. In this particular patient the
gastrin secreting tumor
is cafeteria but there are multiple additional
tumors in this patient so we wanna look and watch for the gastric wall
thickening, especially in the Zollinger-Ellison patients. On CT, the imaging for neuroendocrine tumors is best during the
arterial phase of the bolus injection - as opposed to looking during the portal phase.
we can see in this patient here very clearly that there are two enhancing
lesions in the tail of the pancreas.
However, when we look at the portal phase images from the same study, it's very difficult
to identify these lesions as
showing abnormal a differential contrast enhancement. carcinoid tumor
So, in summary, multiple endocrine neoplasia can be summarized as the
three Ps syndrome
or Wermer's syndrome: pituitary, parathyroid
and pancreatic tumors. Remember the 3 P's and also remember tha the doctors are on
double secret probation
I'm Jim Smyrna topless and thank you for listening
I hope you enjoy the new year