Oncology - Pancreatic Cancer

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Pancreatic Cancer
Pancreatic Cancer
Pancreatic adenocarcinoma is the fourth leading cause of cancer
death in the Western hemisphere.
Worldwide, pancreatic cancer is the eighth most common cause
of death from cancer in both sexes combined, a relative position
higher than for incidence (thirteenth) because of the very poor
prognosis.
Fewer than 5% of all patients are still alive 5 years after initial
diagnosis. The collective median survival time of all patients is
4-6 months.
Despite the poor prognosis of patients with pancreatic cancer,
surgical resection is still the only potentially curative treatment for
the disease.
Pancreatic Cancer
Pancreatic cancers can arise from both the exocrine and
endocrine portions of the pancreas.
Of pancreatic tumors, 95% develop from the exocrine portion
of the pancreas and adenocarcinomas account for 75% of all
pancreas cancers.
Normal Pancreas
pancreatic carcinoma: the pancreas is bisected
along its longitudinal axis revealing a large
adenocarcinoma of the head
Pancreatic Cancer
Approximately 75% of all pancreatic carcinomas occur within the
head or neck of the pancreas, 15-20% occur in the body of the
pancreas, and 5-10% occur in the tail.
Typically, pancreatic cancer
first metastasizes to
regional lymph nodes, then
to the liver, and less
commonly, to the lungs.
It can also directly invade
surrounding visceral organs
such as the duodenum,
stomach, and colon.
TNM staging of pancreatic carcinoma. T1-T4=local tumor
extension; N=lymph node; M=metastasis.
Pancreatic Cancer
Preferred Examination:
1. US is often the initial test in symptomatic patients.
2. Multisection CT is generally accepted to be the first
line of investigation in a patient with suspected
pancreatic cancer.
3. If the patient is clinically jaundiced and when biliary
ductal dilatation is demonstrated on ultrasonographic
examination, endoscopic retrograde
cholangiopancreatography (ERCP) is the next
investigation of choice with a view to a drainage
procedure.
4. MRI could be used to evaluate the pancreas in
obstructive jaundice if the mass is not demonstrable
with CT and US.
5. In the detection and staging of small tumors,
endoscopic US (EUS) can be reliable.
Pancreatic Cancer
Ultrasound
US is often the initial test in symptomatic patients.
US is used for diagnosis rather than staging, although liver metastasis and
ascites may be seen.
normal anatomy
Pancreatic Cancer
Ultrasound
On US, pancreatic tumors are seen as hypoechoic mass lesions that become
more heterogenous in echotexture with increasing size.
Pancreatic Cancer
Endoscopic US
Recent evidence suggests that EUS is similar to CT in diagnosis and staging of
pancreatic cancer. EUS requires special endoscopic skills and expertise, and it is
less readily available worldwide.
A 2.5cm round, hypoechoic
tumor is identified in the the
region of the genu. The
superior mesenteric vein
can be seen separate from
the tumor.
Invasion of the dilated
CBD by a large irregular
hypoechoic tumor located
in the head of pancreas.
A large hypoechoic tumor is seen
to invade the portal vein (arrow),
with loss of tumor-vessel interface
and tumor extension into vessel
lumen. The dilated CBD contains
echogenic sludge.
Pancreatic Cancer
Endoscopic US
Pancreatic Cancer, T4,
vascular invasion
Pancreatic head tumor mass visualized by
EUS as a 3 cm hypoechoic mass at the level
of the pancreatic head, with dilatation of the
common bile duct and posterior invasion of
the portal vein.
Pancreatic Cancer
At present, CT is the most widely used and most sensitive test for
an evaluation of the pancreas for pancreatic carcinoma.
Dynamic CT has a detection rate of approximately 99%.
Multisection CT should be the first-line study for detecting this
tumor and for evaluating its resectability.
Features suggestive of underlying pancreatic cancer include the following:
1. alterations in morphology of the gland with abnormalities of CT
attenuation values,
2. obliteration of peripancreatic fat,
3. loss of sharp margins with surrounding structures,
4. involvement of adjacent vessels and regional lymph nodes,
5. pancreatic ductal dilatation,
6. pancreatic atrophy,
7. obstruction of the common bile duct (CBD).
Pancreatic Cancer
CT Findings
Drawing shows T1 tumor, which is
defined as being equal to or
smaller than 2 cm in maximum
diameter and confined to pancreas,
and T2 tumor, larger than 2 cm and
confined to pancreas
Axial CT image shows stage
T1 pancreatic ductal
adenocarcinoma
From: Diagnosis, Staging, and Surveillance of Pancreatic Cancer
Eric P. Tamm et al. AJR 2003; 180:1311-1323
Pancreatic Cancer
CT Findings
Drawing shows T3 tumor, defined
as tumor that may extend beyond
pancreas but without involvement
of celiac axis or superior
mesenteric artery.
Contrast-enhanced axial CT image shows T3 tumor that
has involved common bile duct, requiring a stent, and
that extends medially beyond confines of pancreatic
head. Tumor is separated from superior mesenteric
vein (long arrow) and superior mesenteric artery (short
arrow) by fat plane (type A relationship). Note that
tumor involves duodenum (arrowhead).
From: Diagnosis, Staging, and Surveillance of Pancreatic Cancer Eric P. Tamm et al. AJR 2003; 180:1311-1323
Pancreatic Cancer
CT Findings
Drawing shows T4 tumor, defined
as primary tumor involving either
superior mesenteric artery or
celiac axis.
Contrast-enhanced axial CT image
shows pancreatic tumor (white arrows)
engulfing celiac axis. Short black
arrow = splenic artery, long black
arrow = common hepatic artery.
From: Diagnosis, Staging, and Surveillance of Pancreatic Cancer Eric P. Tamm et al. AJR 2003; 180:1311-1323
Pancreatic Cancer
Preferred Examination:
1. US is often the initial test in symptomatic patients.
2. Multisection CT is generally accepted to be the first
line of investigation in a patient with suspected
pancreatic cancer.
3. If the patient is clinically jaundiced and when biliary
ductal dilatation is demonstrated on ultrasonographic
examination, endoscopic retrograde
cholangiopancreatography (ERCP) is the next
investigation of choice with a view to a drainage
procedure.
4. MRI could be used to evaluate the pancreas in
obstructive jaundice if the mass is not demonstrable
with CT and US.
5. In the detection and staging of small tumors,
endoscopic US (EUS) can be reliable.
Pancreatic Cancer
Endoscopic retrograde cholangiopancreatography (ERCP)
and percutaneous transhepatic cholangiography (PTC)
• Before the widespread availability of ERCP, PTC was often used to delineate
the biliary anatomy preoperatively.
• ERCP has largely replaced PTC as it has several major advantages.
• The advantages of ERCP over PTC are that it avoids liver puncture with the
accompanying risk of bile leakage and haemorrhage and allows exclusion of
other gastroduodenal disease, diagnosis of periampullary tumours, and
imaging of the pancreatic duct. Brushing and biopsy specimens can also
obtained for cytological and histological examination.
• Both endoscopic retrograde cholangiopancreatography and percutaneous
transhepatic cholangiography allow the insertion of biliary stents
Pancreatic Cancer
Endoscopic retrograde cholangiopancreatography (ERCP)
ERCP has a sensitivity of 95% and a
specificity of 85% for pancreatic
malignancy.
Most pancreatic carcinomas arise
from the ductal epithelium and
produce complete or partial ductal
obstruction.
ERCP image
shows dilated
biliary tree and
obstruction of
common bile
duct
associated
with tumor in
pancreatic
head.
Pancreatic Cancer
Percutaneous transhepatic biliary drainage (PTBD)
Obstructive jaundice warrants
palliation if the patient has pruritus or
right upper quadrant pain or has
developed cholangitis.
Biliary obstruction from pancreatic
cancer is usually best palliated by the
endoscopic placement of plastic or
metal stents.
When endoscopic biliary drainage is
unsuccessful or is contraindicated,
percutaneous transhepatic biliary
drainage (PTBD) is recommended.
Percutaneous transhepatic
cholangiogram showing a catheter in a
dilated common bile duct with an
abrupt, irregular stricture at the lower
end, indicative of a pancreatic cancer
Pancreatic Cancer
MRI Findings
The role of MRI in pancreatic cancer has been less well studied than the role
of CT scanning. It does not appear to be superior to spiral CT scanning.
The ability of MRI to demonstrate pancreatic adenocarcinoma largely depends
on the demonstration of deformity of the gland, as reflected in its size, shape,
contour, and signal intensity characteristics.
T1
Thin-section helical CT image obtained
during pancreatic phase reveals large
pancreatic tumor with tumor surrounding
celiac trunk and hepatic artery.
T1 cont
Extent of vascular encasement is better
depicted by CT scan than by MR images.
From: Diagnosis and Staging of Pancreatic Cancer …
Schima W et al. AJR 2002; 179:717-724
Pancreatic Cancer
MRI Findings
The normal pancreas is of
low signal intensity on T1weighted images and of
intermediate signal on T2weighted images, with a
variable amount of fat in
the gland parenchyma.
Transverse T1-weighted fatsuppressed image shows
verified adenocarcinoma of
the pancreatic head
Adenocarcinoma was
visible as a low-signalintensity tumor.
From: Prospective Evaluation of Pancreatic Tumors … E. L. Hänninen et al. Radiology 2002;224:34-41.
Pancreatic Cancer
Compared with other modalities, MRI appears to be more valuable for staging
the extent and spread of pancreatic carcinoma than for tumor detection of
lesions smaller than 2 cm.
ERCP image shows
slight narrowing of
pancreatic duct and
ductal dilatation.
Sphincterotomy was
performed, and
pancreatic stent was
placed.
Contrast-enhanced CT
scan fails to depict
tumor (arrow) around
stent in dilated
common bile duct.
From: Diagnosis and Staging of Pancreatic Cancer … Schima W et al. AJR 2002; 179:717-724
Unenhanced T1-weighted MR
image shows inhomogeneity
of pancreatic head, but does
not show tumor.
Pancreatic Cancer
Magnetic resonance cholangiopancreatography (MRCP)
MRCP is as sensitive as ERCP and may prevent inappropriate explorations
of the pancreatic and bile ducts in patients with suspected pancreatic
carcinoma in whom interventional endoscopic therapy is unlikely
Coronal image from MRCP
shows double-duct sign
caused by obstruction by
tumor. Dilated common bile
duct and dilated pancreatic
duct are seen proximal to
abrupt cutoff.
From: Diagnosis, Staging, and Surveillance of Pancreatic Cancer Eric P. Tamm et al. AJR 2003; 180:1311-1323
Pancreatic Cancer
Magnetic resonance cholangiopancreatography (MRCP)
MR pancreatogram reveals a dilated
pancreatic duct proximal to the
obstructing pancreatic head mass.
ERCP helps confirm the dilatation of the
pancreatic duct in the body and the
distal stricture.
From: MR Pancreatography: A Useful Tool for Evaluating Pancreatic Disorders Ann S. Fulcher et al. Radiographics. 1999;19:5-24.
Pancreatic Cancer
MRI Findings
Coronal oblique MRCP demonstrates
pancreatic duct obstruction in the
head with proximal dilatation of both
pancreatic duct (PD) and common bile
duct (CBD), which is referred to as the
double duct sign.
Coronal MR angiogram in the venous
phase shows vascular infiltration of the
portal vein and venous confluens. Note
the consecutive mesenteric collateral
formation.
From: Prospective Evaluation of Pancreatic Tumors … E. L. Hänninen et al. Radiology 2002;224:34-41.
Pancreatic Cancer
Upper GI barium studies may
reveal an extrinsic impression
of the mass on the
posteroinferior aspect of the
antrum of the stomach.
This is known as antral „pad
sign”.
Pancreatic Cancer
The medial margin of the
descending duodenum may be
pulled medially at the level of the
ampulla, forming a reversed-3
appearance.
This is known as Frostberg 3 sign.
Duodenal invasion at
the level of papilla
major demonstrated
by upper GI
endoscopy
Pancreatic Islet Tumors
These tumors are far less common than the nonendocrine tumors listed above. They account for about
1% of pancreatic cancers. It is very important that
endocrine tumors be distinguished from non-endocrine
because the treatments for the two types are very
different.
The endocrine tumors may produce highly active
hormones and therefore have very dramatic symptoms
Pancreatic Islet Tumors
Pancreatic Cancer
Pancreatic cancer screening
• No reliable screening tests are available for detecting early
pancreatic cancer in asymptomatic patients.
• Imaging techniques are not suitable as screening tests because
of many factors, including cost and/or their invasive nature.
• Tumor markers are nonspecific.
• Screening for pancreatic cancer is not recommended at this
time.
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