Neoplastic States of Pancreas/Gallbladder Flashcards
What are two vessels below neck of pancreas?
SMA and SMV
What are three important histological components of pancreas?
Acini
Islets
Ducts
What are two broad categories of pancreas lesions?
Cystic and Non-cystic
What are risk factors for pancreatic cancer?
Age>60 Smoking Obesity/diet Alcohol abuse Pancreatitis Diabetes Genetic predisposition (fan history and syndromes like FAP, Lynch, MEN)
What are clinical features of pancreatic cancer?
Pain Obstructive jaundice Weight loss Anorexia Migratory thrombophlebitis
Often asymptomatic until invades adjacent structures
What is precursor of invasive ductal adenocarcinoma?
Pancreatic intraepithelial neoplasia (PanIN)
Increases in prevalence with age
Describe molecular progression of invasive ductal adenocarcinoma
Telomere shortening and KRAS mutation: PanIN1
Inactivation of CDKN2A: PanIN2
Inactivation of SMAD4: PanIN3
TP53: invasive ductal adenocarcinoma
What is surgical procedure for tumors at head/neck of pancreas?
Whipple procedure (aka pancreaticoduodenectomy)
Describe gross appearance of invasive ductal adenocarcinoma
Firm with poorly defined and infiltrative borders
Yellow-white in color
Hemorrhage/necrosis
Can appear cystic
Describe histological appearance of ductal invasive adenocarcinoma
Desmoplastic stroma with fibroblasts and inflammatory cells
Can have haphazard irregularly shaped glands
Can have perineurial, vessel or lymphatic invasion
Irregular nuclear contours, N/C up, atypia
What is the grading stages of adenocarcinoma?
Well differentiated==>poorly differentiated (how much of tumor is glandular)
At what stage are most pancreatic cancers diagnosed?
Late stage with distant metastases
What is 5 year survival for pancreatic ductal adenocarcinoma?
Real bad– 25% for local, 10% for regional 2% for distant
How are differentiation and grade determined?
Differentiation= how close do neoplastic cells resemble non-neoplastic counterparts
Grade: look at mitoses and Ki-67 to measure aggressiveness
Where does PanNET arise?
Usually a solitary, well-demarcated tumor that can occur anywhere along length of pancreas
Describe gross appearance of well-differentiated PanNET
Well circumscribed tumor that is tan-pink and lacks necrosis
Describe histology of well-differentiated PanNET
Well circumscribed lesion with surrounding capsule
Cords with dense collagenized stroma
Cells have abundant cytoplasm and salt/pepper chromatin
What are two categories of NETs
Which ones are more common?
Function (hormone producing) and non-functioning
NF>insulinomas>gastrinomas>glucagonomas
What are three major genes/pathways of well-differentiated PanNETs?
MEN1
PTEN/TSC2==>Activation of mTOR signaling
DAXX/ATRX
Describe poorly differentiated PanNET: Prevalence, age, clinical behavior
2% of PanNETs
Occurs in adults
Highly aggressive clinical behavior– local and widespread distant mets
Describe gross appearance of poorly differentiated PanNET
Infiltrative, aggressive
Describe histological appearance of poorly-differentiated PanNET
small round blue cells with scant cytoplasm and hyper chromatic nuclei
Necrosis
Aggressive/infiltrative, metastatic
What is a pancreatic pseudocyst?
How common is it?
When do you see it?
Cystic lesion that LACK true epithelial lining
75% of pancreatic cysts
Arises after bout of acute pancreatitis or traumatic injury
What is serous cystadenoma?
Prevalence
Sex, age
Benign neoplasm that usually occurs in tail of pancreas
25% cystic neoplasms of pancreas
More common in women; 6th-7th decade
How does pancreatic serous cyst adenoma present?
Nonspecific symptoms such as abdominal pain
What is most common genetic abnormality of serous cyst adenoma?
Inactivation of VHL tumor suppressor gene
Describe gross appearance of serous cystadenoma
How is it normally treated?
Multi cystic with spongelike appearance
Cured by surgery
Mucinous cystic neoplasm: What is it? Location, sex, presentation
Painless growing mass in tail of pancreas almost always in women.
It is filled with thick, tenacious mucin and is composed of columnar mutinous epithelium
What are histological features of mucinous cystic neoplasm? (2)
Inner epithelial layer composed of tall mucin-secreting cells
Dense cellular ovarian-type stroma
What are possible progression of mucinous cystic neoplasm? (2)
Dysplasia
Invasive carcinoma
Describe the epidemiology of intraductal papillary mucinous neoplasm (IPMN)
Most frequent cystic mucinous tumor in pancreas
M>W; age=66yo
Predominantly head of pancreas
What are general features of IPMN?
Grossly visible intraductal proliferation of neoplastic mucin-producing cells
Communicated with ductal system
What are the distinctions between main duct vs. branch duct IOMN?
Main duct type: Diffusely or focally dilated, contains abundant mucus secretion
Branch duct: More indolent course
Describe gross features of IPMN
Branch: Circumscribed cystic lesion or cluster of mildly dilated ducts
Main: Dilated duct
Gallbladder adenocarcinoma Epidemiology: Prevalence, sex, geography, major risk factor
Most common malignancy of extra hepatic biliary tract
W>M
Chile/Bolivia/India
Gallstones is major risk factor
What is typical prognosis for gallbladder adenocarcinoma?
usually diagnosed at advanced stage– 5 year survival
Gross appearance of gallbladder adenocarcinoma
Large exophytic tumor
Calcification leading to porcelain gallbladder