RECALL: What is the difference between the Sphincter of Oddi and the Ampulla of Darth Vader?
Sphincter of Oddi = Opening on the duodenum that the Ampulla of Vader empties into
Ampulla of Darth Vader = Joining of the pancreatic duct and the common bile duct
TRUE or FALSE: Hormones made by the pancreas are secreted into the pancreatic duct
FALSE!! They are HORMONES, so secreted into blood!
Digestive enzymes are secreted into the pancreatic duct
RECALL: List the major products secreted by each of the following pancreatic islet cells:
- Alpha
- Beta
- Delta
- F (PP) cell
Alpha: Glucagon
Beta: Insulin
Delta: Somatostatin
F (PP): Pancreatic polypeptide
What are 6 types of pancreatic neuroendocrine tumors?
1) Gastrinoma
2) Insulinoma
3) Glucagonoma
4) Somatostatinoma
5) VIPoma
6) PPoma
Gastrinomas, also known as what Syndrome? They are characterized by the overproduction of what by which cells in the stomach,duodenum, and pancreas
Zollinger-Ellison Syndrome
Overproduction of GASTRIN
by the
G cells
- Gastrin stimulates gastric acid secretion in stomach to help with motility
Where is the most common location of a gastrinoma?
Gastrinomas can be associated with which MEN syndrome?
Duodenum, then pancreas
MEN I
70% of gastrinomas are (malignant/benign), occur in (females/males), and are (sporadic/heriditary). What is the first line treatment?
70% are MALIGNANT, occur in MALES, and are SPORADIC
tx with PPI's (often won't work, but worth a shot!)
90% of all gastrinomas are located in what surgical area? List the rough location of this triangle.
Passaro's triangle
- Cystic duct
- Border of 2nd/3rd parts of duodenum
- Junction of neck and body of pancreas
List 3 diagnostic features of gastrinomas
1) Elevated gastric acid output => duodenal/gastric ulcers
2) Elevated plasma gastrin, fasting
above 500> pg/ml
(normal < 100)
3) Increased gastrin response to IV secretin (instead of suppressed)
What is the MOST sensitive imaging modality for diagnosing gastrinomas?
What are some other imaging modalities for diagnosing gastrinomas?
Somatostatin scintigraphy (Octreotide scan) - 85%
CT scan, Endoscopic ultrasound, Angiography (all ~65% sensitive)
What is the treatment of choice for gastrinomas?
Due to excess gastric acid, use
PROTON PUMP INHIBITORS
(omeprazole) to control acid hypersecretion
- Also, must establish MEN 1
Pancreatic surgery can what basic subtypes? What is the main difference between the two?
Either be
ENUCLEATION
, which is removal of the tumor WITHOUT removing pancreatic tissue (less than 2 cm!), or
RESECTION
in which part of the pancreas is removed
If the tumor is in the HEAD of the pancreas, what is the surgery performed?
Whipple procedure (pancreaticoduodenectomy)
Whipple resection = 60-70% of the pancreas
(blood supply will be damage)
If the tumor is in the TAIL of the pancreas, what is the surgery performed?
Distal pancreatectomy w/ or w/out splenectomy
Distal resection = 50-60% of the pancreas
TEST: How much of the pancreas needs to be kept intact in order to have good
exocrine and endocrine
function?
At least
20%
TRUE or FALSE: A pancreatic HEAD tumor will require resecting more of the pancreas than a pancreatic tail tumor
TRUE!
What is the most commonly performed pancreatic surgery for small tumors
(< 2cm)
with no spread?
Laparoscopic or open ENUCLEATION with intraoperative ultrasound
What is the most common FUNCTIONAL neuroendocrine tumor?
Insulinoma
HY/TEST: Insulinomas present with what 3 major symptoms? What is this called?
WHIPPLE'S TRIAD
1) Hypoglycemia
2) Fatigue, confusion, blurry vision, weakness (signs of hypoglycemia)
3) Relief of symptoms with glucose admin
TRUE or FALSE: Most insulinomas are benign
TRUE or FALSE: Most insulinomas are large and isolated
TRUE
FALSE, SMALL and isolated
TEST: What are the two diagnostic criteria for insulinomas?
1)
Elevated
fasting plasma
insulin
2)
FAILURE of insulin suppression
in fasting hypoglycemia (normally, insulin levels should drop)
What is the first imaging test you would do for an insulinoma? What is the most SENSITIVE method of detection?
First: CT scan -> shows "blush on arterial phase"
Most sensitive: Intraoperative ultrasound
TEST: Octreotide scan (is/is not) useful for insulinomas. Why?
IS NOT useful, as insulinomas do NOT light up on the scan
What are some pharmacological treatments for insulinomas?
Diazoxide or somatostatin => block release of insulin [used in inoperable tumor pts]
What is the surgical treatment of choice for an insulinoma?
If small: Laparoscopic or open enucleation
If large: Pancreaticoduodenectomy (if in head)
Glucagonomas are most commonly found in the (head/neck/tail) of the pancreas
TAIL
TRUE or FALSE: Most glucagonomas are malignant and present w/ necrolytic migratory erythema (perioral/pretibial/intertriginous)
TRUE! (80% -> large tumors 5-10 cm) w/ erythematous scaly rash
Diagnostically, glucagonomas show (increased/decreased) serum levels of glucagon and (increased/decreased) plasma levels of amino acids, causing what?
INCREASED glucagon (above 500 pg/ml)
DECREASED amino acids (causing a rash) causing:
1 hypoaminoacidemia (see above)
2 mild diabetes
3 cachexia
4 venous thrombosis (often presenting symptoms)
What is the most sensitive scan for Glucagonomas?
Octreotide scan (somatostatin scintinography) - 85% sensitive
AGAIN: Which pancreatic tumor will not light up on the Octreotide scan?
Insulinoma
TEST: What is the FIRST thing you do to treat glucagonomas?
Correct the malnutrition!!
before surgery!! (total parental nutrition and insulin) & aim to correct hypoaminoacidemia
What is the most malignant tumor of the pancreas?
Somatostatinoma (90%)
TRUE or FALSE: Somatostatinomas are commonly found in the head of the pancreas, follow-up question where are 1/4 found?
TRUE! w/ 25% in small bowel
What syndromes accompany Somatostatinomas?
DM II, gallstones, streatorrhea (excess fat in feces), hypochlorhydria
What test can help diagnose somatostatinomas?
Fasting plasma somatostatin assay
(will be elevated)
What is the most sensitive imaging modality for diagnosing somatostatinomas?
Octreotide scan -somatostatin scintinography - 85% sensitive
(everything else is 65%
What is the surgical treatment of choice for Somatostatinomas?
Laparoscopic or open pancreaticoduodenectomy (Whipple b/c in head of pancreas)
VIPomas are also known as WDHA Syndrome, which includes what 3 symptoms?
1) Watery Diarrhea
2) Hypokalemia
3) Achlorhydria
What are elevated in VIPomas? Where are they commonly found in the pancreas? Surgical option?
Vasoactive intestinal peptide
(VIP) and
calcium
are elevated
Found in the TAIL of the pancreas -> laparoscopic or open distal pancreatectomy w/ or w/out splenectomy
What is the diagnostic criteria for VIPomas?
Fasting plasma VIP levels greater than 500 pg/mL
in the setting of secretory diarrhea (which is diagnosed if diarrhea persists when the patient is fasting)
What is the most sensitive imaging modality for diagnosing VIPomas?
Octreotide scan
The goal of pre-op treatment of VIPomas is what?
Fluid resuscitation
and rehydration PRIOR to surgery, because you want to
replenish all that is lost from the watery diarrhea
=> make sure pt is stable/balanced before surgery
TRUE or FALSE: PPomas are functional
FALSE!
PPomas are most commonly found ________ on CT scan, commonly presenting with these 3 symptoms
INCIDENTALLY
Symptoms:
1) Weight loss
2) Bleeding
3) Bowel obstruction
What is the diagnostic criteria for PPomas?
Fasting pancreatic
polypeptide levels GREATER than 300 pg
/mL
- Also, if more than half of the tumor stains positive for pancreatic polypeptide via IHC
What is the most sensitive imaging modality for PPomas? Where is it found? Surgical options?
Octreotide scan (same margins as above)
Can be found in head (Whipple) or tail (distal pancreatectomy +/- splenectomy)
What are some complications of
pancreatic surgery in general
?
Pancreatic leak
Bleeding
Pancreatitis
Abscess
Pancreatic fistula
REVIEW: Besides _________, all other pancreatic tumors shows up MOST sensitive on the Octreotide scan
Besides INSULINOMAS!!