Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
Neuroblastoma
|
- MALIGNANT catecholamine-producing tumor of early childhood
- urinary catecholamaines and metabolites are same as those seen in pheochromocytoma - causes hypertension - origicantes in adrenal medulla and presents as abdominal mass |
|
describe the genetics behind neuroblastoma
|
- occasionally converts into more differentiated "ganglioneuroma"
- tumor is characterized by amplification of N-myc oncogene with thousands of copies per cell - malignant cells sometimes differentiate into benign cells (seen as a reduction in gene amplification) |
|
describe the N-myc gene seen in neuroblastoma
|
- thousands of copies of N-myc in a cell
- amplification results in karyotypic changes (homogeneously staining regions or double minute chr) - number of N-myc genes correlates to the aggressiveness of the tumor |
|
list the endocrine tumors (islet cell tumors)
|
1. Insulinoma (beta cell tumor)
2. Gastrinoma 3. Glucagonoma (alpha cell tumor) |
|
insulinoma (beta cell tumor)
|
- most common islet tumor
- can be either benign or malignant - greatly increased insulin secretion - increased C-peptide levels - see Whipple triad |
|
how do you differentiate endogenous insulin from exogenous insulin administration?
|
- look for levels of C-peptide
- C peptide is broken off from the pre-insulin molecule during the synthesis of insulin - high C-peptide is increased in patients with insulinoma - not seen in the bolus given with commercial insulin |
|
Whipple triad
|
1. episodic hyperinsulinemia and hypoglycemia
2. CNS dysfunction related to hypoglycemia (confusion, anxiety, stupor, convulsions, coma) 3. reversal of CNS symptoms with glucose administration |
|
what CNS changes do you see with hypoglycemia?
|
- confusion
- anxiety - stupor - convulsions - coma |
|
Gastrinoma
|
- a type of islet cell tumor
- often malignant - can occur in extrapancreatic sites - results in gastrin hypersecretion and hypergastrinemia - associated with Zollinger-Ellison syndrome |
|
Zollinger-Ellison syndrome
|
- gastric hypersecretion of HCl
- recurrent peptic ulcer disease - hypergastrinemia |
|
Glucagonoma (alpha cell tumor)
|
- rare islet cell tumor
- results in secondary DM - causes skin lesion called necrolytic migratory erythema |
|
when do you see necrolytic migratory erythema?
|
a classical symptom observed in patients with glucagonoma and is present in 80% of cases. Associated NME is characterized by the spread of erythematous blisters and swelling across areas subject to greater friction and pressure, including the lower abdomen, buttocks, perineum, and groin.
|
|
VIPoma
|
- rare islet cell tumor
- tumor that secretes vasoactive intestinal peptide (VIP) - assocatied with the WDHA syndrome: Watery Diarrhea, Hypokalemia, and Achlorhydria |
|
WDHA syndrome (Verner-Morrison sydrome)
|
- aka pancreatic cholera
- Watery Diarrhea, Hypokalemia, Achlorhydria - seen in VIPoma (an islet cell tumor) |
|
Multiple Endocrine Neoplasia (MEN) Syndromes
|
- autosomal dominant
- more than one endocrine organ is HYPERfunctional - may be associated with hyperplasias or tumors 1. MEN I (Wermer syndrome) 2. MEN IIa (Sipple syndrome) 3. MEN IIb (MEN III) |
|
MEN I (Wermer syndrome)
|
- hyperplasias or tumors of the PITUITARY, PARATHYROID, or PANCREATIC islets
- can also include hyperplasias of the thyroid or adrenal cortex - pancreatic component can manifest as: Zollinger- Ellison syndrome, hyperinsulinism, pancreatic cholera - linked to mutations in the MEN I gene |
|
MEN IIa (Sipple sydrome)
|
- pheyochromocytoma, medullary carcinoma of the thyroid, and hyperparathyroidism from hyperplasia or tumor
- linked to mutations in the ret oncogene |
|
MEN IIb (MEN III)
|
- pheochromocytoma, medullayr carcinoma, and multiple mucocutaenous neuromas or ganglioneuromas
- does NOT include hyperparathyroidism (like MEN IIa) - linked to mutations in the ret oncogene (not the same ones as MEN IIa) |