NEUROENDOCRINE TUMORS Flashcards
What are NET’s?
What kinds are there? 3
are neoplasms that arise from cells of the endocrine and nervous tissue.
Rare
Benign
Malignant
Neuroendocrine Tumors
can be found where?
6
1. Multiple Endocrine Neoplasms --MEN type I & II 2. Insulinomas 3. Gastrinomas 4. VIPomas 5. Glucagonomas
- Carcinoid
Neuroendocrine Tumors. Whats the difference between well-differentiated and undifferentiated tumors?
Well-Differentiated- slow growing and easliy treatable
Undifferentiated- harder to treat and faster growing
The biologic behavior of these two entities differs remarkably, and the distinction is important for planning therapy
MEN Syndromes are conditions that cause what?
How are they usually acquired?
Conditions which cause overactivity and enlargement and tumors of certain endocrine glands.
Usually inherited conditions.
Autosomal dominant – each child has 50% chance of inheriting the gene.
Families will have only one type of MEN, they are not at risk for developing another type of MEN.
Tumors associated with MEN 1? 3
MEN 2a? 3
MEN 2b? 3
Types are distinguished by patterns of organs affected
MEN 1 = parathyroid tumors, pancreatic tumors, pituitary tumors
MEN 2a = medullary thyroid cancers, pheochromocytoma, parathyroid
MEN 2b = Medullary thyroid cancers, pheochromocytoma, neuromas (no parathyroid!)
Almost all who inherit MEN1 develop over-activity of the what?
What is the first clinical manifestation?
What symtpoms do we see in hyperparathyroidism? 4
over-activity of the parathyroid.
(which is usually the first clinical manifestation.- hyperparathroidism,
bones, stones, moans and groans
What will develop probblems next in MEN1?
What will be over produced because of this? 2
What occurs in about 15-20% of pts with MEN1?
Pancreas over-activity is next. (Occurs in about 75% of patients)
- Gastrin over-production common after 30 years of age. (about 15% of patients)
- Insulin over-production common under 30 years of age. (about 15% of patients)
Pituitary adenoma occurs in about 15-20% of patients
Should everyone with an endocrine gland problem be tested for MEN1?
NO
People who have over-activity of 2 or more of the glands involved in MEN should be examined for MEN1
Does MEN1 cause cancer??
Usually not, typically benign tumors
Pancreas is most likely culprit if it does happen
Diagnostic for MEN?
Regular screening for MEN 1 monitoring (family history of it)?
3
Predictive genetic testing – (chrom 11 q 13)
Regular screening for endocrine gland overactivity:
- Calcium & PTH - yearly from the age of 5
- Prolactin
- Gastrin
Treatment for MEN 1
- Hyperparathyroidism?
- Pituitary adenomas? 4
- Pancreatic/Gastrointestinal tumors?
2
- Surgery
2. Dopamine agonist --Cabergoline (1st choice) --Bromocriptine (2nd choice) Transsphenoidal surgery
- Proton pump inhibitor
Surgery
MEN 2a affected organs?
3
- Thyroid
- Adrenal (adrenal medulla)
- -Pheochromcytomas - Hyperparathyroidism
What is the men 2a gene abnormality?
RET proto-oncogene chromosome 10
MEN 2a prophylactic treatment?
Will almost certainly develop medullary thyroid cancer!!
Very aggressive
Begins early in life and grows quickly
- Patients with MEN2 gene should have their thyroid surgically removed while they are young.
Other diseases for MEN 2a?
2
- Cutaneous lichen amyloidosis
2. Hirschsprung disease (no nerve cells to keep the colon moving, no bowel movements)
Testing for MEN2a:
Diagnosis?
Monitoring? 3
Predictive genetic testing – ret protooncogene mutation
Regular screening for endocrine activity:
Screening is aimed at detecting the earliest signs of Medullary Ca.
1. pentagastrin causes raised levels of calcitonin within 2-3 minutes in affected individuals.
- Urinary catecholamine (adrenaline and noradrenaline)
- Calcium or parathyroid levels should also be obtained every 2 years.
MEN 2b causes what kind of tumors/ diseases?
4
Medullary thyroid cancers
Pheochromocytoma
Mucosal neuromas
Marfanoid Habitus
What is Mucosal neuromas?
How are they treated?
small benign tumors of nervous tissue found in the mucosa of the body (e.g. the linings of the nasal sinuses, the lips, tongue, the respiratory tract, the gastrointestinal tract, the biliary tract and the pancreatic systems).
They are treated conservatively, removed only if they cause problems (e.g. by obstruction airways or the passage of food).
What is Marfanoid Habitus
4
- Arachnodactyly- long fingers and extremities
- Tall with disproportionately long legs and arms - the span of the arms is greater than the height
- pectus excavatum
- spinal abnormalities
Testing forMEN 2b
2
Same as for MEN 2a, except that screening for parathyroid abnormalities is not done.
Therefore the pentagastrin test or medullary thyroid cancer and the urinary catecholamine tests are used.
Treatment of MEN 2A and MEN 2B focuses on what?
With either syndrome, it may be necessary to perform what?
If pheochromocytomas are present, they should be what?
surgical removal of tumors that might spread to other parts of the body or cause life-threatening biochemical disturbances.
operations in stages to minimize the overall risk of complications.
removed in a separate operation before proceeding with any other operations.
Confirmed medullary thyroid cancer should be treated with what? 2
In most cases, it is recommended that the lymph node dissection should be performed where?
2
- surgical removal of the entire thyroid gland,
- followed by careful exploration and dissection of the lymph nodes in the neck.
in the central compartment from the
- hyoid bone to the innominate veins and
- medial to the jugular veins
Insulinoma is a tumor of what?
Describe the pathology of the tumor and what it causes?
Rare beta-cell tumor (in the islets of Langerhans) that secretes insulin.
Hyperinsulinemia – not responsive to falling glucose concentrations in the fasting state – result is persistent hypoglycemia.
What are the signs of insulinoma?
3
- Patients eat frequently to prevent hypoglycemia
- Gain weight
- Symptoms typically begin with evidence of CNS glucose lack