Adenocarcinoma of the Exocrine Pancreas Flashcards
(70 cards)
Epidemiology
- While the increasing and aging population is the most likely cause of this increase
- The risk of pancreatic cancer increases with age beyond the sixth decade; the mean age at diagnosis is 72 years.
Which rank cancer deaths in United States.
The third most common cause of cancer deaths in United States.
Hereditary risk factors associated with development of pancreatic cancer»_space; PRSS1
Familial pancreatitis
> > Mutation results in chronic pancreatitis and 40% lifetime risk of PDAC
STK11
Peutz-Jeghers syndrome
> > Mutation results in >100-fold increase in risk of PDAC
CDKN2A
Familial atypical mole and multiple melanoma syndrome
> > Mutation leads to increased risk of melanoma and >40-fold increase in risk of PDAC
CFTR
Cystic fibrosis
> > Thick secretions result in chronic pancreatitis and 30-fold increase in risk of PDAC
BRCA2
Hereditary breast and ovarian cancer
> > Mutation results in elevated risk of breast and ovarian cancer and 10-fold increase in risk of PDAC
MLH1
Lynch syndrome
> > Mismatch repair gene mutation leads to increased risk of colon cancer and eightfold increase in risk of PDAC
APC
Familial adenomatous polyposis
> > Mutation results in polyposis coli and colon cancer with fourfold increase in risk of PDAC
“Poor Souls Can Crack Bricks Making Aches”
P – PRSS1
S – STK11
C – CDKN2A
C – CFTR
B – BRCA2
M – MLH1
A – APC
RF
Smoking
Obesity
New onset Diabetes
> > elderly patients with new-onset diabetes in the presence of unusual symptoms like weight loss and abdominal symptoms, diagnosis of pancreatic cancer should be considered and may lead to early diagnosis of pancreatic cancer.
familial pancreatic cancer (FPC)
- The remaining 80% of patients with an inherited predisposition but who do not have an identifiable genetic syndrome
- Two or more first-degree relatives with pancreatic adenocarcinoma that do not fulfill the criteria of other inherited tumor syndromes with an increased risk for the development of pancreatic adenocarcinoma.
Pathogenesis of Sporadic Pancreatic Cancer
> > pathogenesis of PDAC, including PDX1, KRAS2, CDKN2A/p16, P53, and SMAD4.
Pancreatic Intraepithelial Neoplasia
PanIN is defined histologically by
» progressive abnormality of the ductal epithelium from columnar metaplasia (PanIN-1A) through carcinoma in situ (PanIN-3).
PanIN-1A, 1B, 2, and 3
PanIN-1A :
» columnar, mucin-producing ductal epithelium that maintains basally located homogeneous nuclei without atypia
PanIN-1B :
» The development of papillary architecture
PanIN-2 :
» denotes the progression from simple papillary growth to evidence of nuclear atypia
» Enlarged nuclei with nuclear crowding
PanIN-3 (carcinoma in situ) :
» complete loss of polarity and marked cytologic atypia
KRAS2 oncogene
> > activated in more than 95% of pancreatic cancers and is thought to be the initiating event in tumorigenesis
> > one of the earliest genetic abnormalities identified in the progression of PanIN to PDAC
CDKN2A/p16, P53, and SMAD4 are tumor suppressor genes
CDKN2A encodes p16 :
» which halts the cell cycle via CDK4/6 inhibition
» Its loss is seen in ~90% of PDACs and progresses from PanIN-1 (30%) to PanIN-3 (71%).
P53:
» regulating apoptosis and cell cycle arrest
» is rarely mutated in PanIN but is altered in 79% of invasive PDACs.
SMAD4 :
» part of TGF-β signaling, is lost in 78% of metastatic PDACs, but less so in early PanIN-3 (20–30%)
Courvoisier , Virchow node, and Sister Mary Joseph node
> > Courvoisier :
slow progressive occlusion more likely to result in ectasia of the organ.
> > Virchow node :
a left supraclavicular node may be palpable
> > Sister Mary Joseph node :
periumbilical lymphadenopathy may be palpable .
> > Blumer shelf
peritoneal dissemination, perirectal tumor involvement may be palpable through digital rectal examination
The left supraclavicular lymph node (Virchow node) , why not right ?
> > gastric, pancreatic, and other GI cancers :
receives lymphatic drainage via the thoracic duct, which collects lymph from most of the body except the right upper quadrant.
> > empties into the left subclavian vein near the left supraclavicular fossa
> > The right supraclavicular node drains only the right head, neck, thorax, and upper limb, so it’s less commonly affected by abdominal cancers.
careful attention should be paid to nutritional values, if surgical intervention is to be considered
prealbumin and albumin levels
Tumor markers
CEA, carbohydrate antigen 19-9 (CA 19-9), and α-fetoprotein.
Of these, CA 19-9 is most sensitive for pancreatic adenocarcinoma, with a sensitivity of approximately 79% and a specificity of 82%
A notable limitation of CA 19-9 testing
> > in the setting of periampullary tumors is the false elevation caused by biliary obstruction
10% to 15% of individuals do not have elevation of the CA 19-9 level, a finding that has been associated with
> > blood Lewis antigen–negative status and is caused by a lack of the fucosyltransferase gene.
CA-19.9 useful for
> > pretreatment evaluation and posttreatment surveillance
predictive and prognostic marker.
normalization of CA 19-9 after neoadjuvant therapy has been suggested as an important prognostic factor
use for identifying patients who will benefit from staging laparoscopy