Download A 68 Year-Old Male Presenting with Fever and Malaise

Metastatic GIST: Correlating
Disparate Radiologic Findings on CT
Joe McQuaid, HMS III
Gillian Lieberman, MD
November, 2007
Our Patient: CH
Clinical Presentation
History of Present Illness
•
•
•
•
68 year-old male
One week history – malaise, chills, low-grade temps
Four days PTA – high grade temperatures to 103.0 °F
Morning of admission – three to four BM’s that were
loose and explosive but not tarry, sticky, or bloody
• ROS upon admission – denies chest pain, cough,
shortness of breath, sputum, dysuria, hematuria,
hematochezia.
• No recent travel history
Past Medical History
• Hypertension
• Hypercholesterolemia
• “Benign esophageal growth” with previous
history of bleeds
• Prostate cancer with surgical resection
• No previous imaging studies on file
Physical Findings
• Vital signs upon admission:
– Tc=100.6 HR=72 BP=98/68 O2=97% on RA
• Physical examination notable for:
–
–
–
–
General: NAD. Mucus membranes clear.
Pulmonary: CTA bilaterally. No wheezes, ronchi, rales.
Cardiac: Normal S1 and S2. No extra heart sounds.
Abdomen: Positive BS. Soft. NTND. No abnormal masses or
organomegaly noted.
– Lymphatics: No cervical, supraclavicular, axillary, inguinal
lymphadenopathy.
• Laboratory Studies:
– WBC=17.1 RBC=3.64 Hgb=10.1 Hct=31.2
– Plt Ct=418
Our Patient: Chest CT
“Please evaluate for infectious etiologies”
Our Patient: Chest CT with Contrast
11 mm solid nodular density
Irregular, “spiculated” margins
BIDMC, PACS
Left upper lobe apex
Our Patient: Chest CT with Contrast
12x6 mm solid, nodular density
with irregular, spiculated margins
Adjacent to the pleura
BIDMC, PACS
Chest CT: Differential Diagnoses
Type of Cause
Neoplasm
Disease Entity
Metastases
BAC
Lymphoma
Infectious
X TB
X Fungal (Histoplasmosis, Aspergillus)
Bacterial (Staph, Klebsiella, Strep)
Noninfectious
Sarcoid
X Rheumatoid
X Silicosis
Wegener’s
Histocytosis
Necrotizing granulomatous vasculitis
Other
X Drug Toxicity
X = Eliminated
Our Patient: Abdominal CT
“Please evaluate for infectious etiologies”
Our Patient: Abdominal CT with Contrast
8.0 x 9.6 x 8.0 cm (AP, transverse,
craniocaudal) heterogeneous lesion,
hypoenhancing compared to the liver
parenchyma
multiple loculations…
…and septations
BIDMC, PACS
Our Patient: Abdominal CT with Contrast
BIDMC, PACS
Multiple hypoattenuating satellite lesions
Abdominal CT: Differential Diagnoses
Type of Cause
Disease Entity
Congenital Cystic
Lesions
Simple cysts
ADPLD
Bile duct harmartomas
Caroli’s disease
Infective Cystic
Lesions
Pyogenic liver abscess
Amebic liver abcess
Hydatid cysts
Neoplastic Cystic
Lesions
Cystic liver metastases
Cystic HCC
Billiary cystadenoma
Undifferentiated embryonal sarcoma
BIDMC, PACS
Companion Patients
Some common radiologic findings of congenital cystic
lesions…
Companion Patient #1:
Simple Hepatic Cysts on CT
• Simple Hepatic Cysts
– Develop from
harmartomatous tissue
– Hypoattenuating lesion on
nonenhanced CT scans
– No enhancement of wall or
contents with contrast
– Round or ovoid, well
defined, with a thin wall
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #2:
ADPLD on CT
• Autosomal Dominant Polycystic
Liver Disease
– Often asymptomatic
– Coexists with renal cysts
– Multiple homogenous,
hypoattenuating lesions
– Regular outline
– No wall enhancement with
contrast
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #3:
Bile Duct Harmartomas on CT
• Bile Duct Harmartomas
– Scattered throughout biliary
tree
– 0.5-1.5 cm in diameter
– More irregular outline
– Do not exhibit a
characteristic pattern of
enhancement with contrast
on CT
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #4:
Caroli Disease on CT
Mortele KJ et al. Radiographics 2001; 21(4)
• Caroli Disease
– Right upper quadrant pain,
fever, jaundince
– Hypoattenuated dilater cystic
structures
– Various sizes
– Communicate with bile duct
system
– “Central dot sign” –
enhancement within dilated
bile duct on CT
Abdominal CT: Differential Diagnoses
Type of Cause
Congenital Cystic
Lesions
Disease Entity
X
X
X
X
Simple cysts
ADPLD
Bile duct harmartomas
Caroli’s disease
Infective Cystic
Lesions
Pyogenic liver abscess
Amebic liver abcess
Hydatid cysts
Neoplastic Cystic
Lesions
Cystic liver metastases
Cystic HCC
Billiary cystadenoma
Undifferentiated embryonal sarcoma
BIDMC, PACS
X = Eliminated
Companion Patients
Some common radiologic findings of infective cystic
lesions…
Companion Patient #5:
Pyogenic Abscess on CT
• Pyogenic Abscess
– Often infection by e coli or
clostridium
– Thick-walled
– Low attenuation on CT
– Rim enhancement with
contrast
– Air pockets are diagnostic of
a gas-forming organism
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #6:
Amebic Liver Abscess on CT
• Amebic Liver Abscess
– Caused by entamoeba
histolytica
– In addition to above features
show perilesion edema
– Peripheral rim enhancement
or “double target sign”
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #7:
Intrahepatic Hydatid Cyst on CT
•
Mortele KJ et al. Radiographics 2001; 21(4)
Intrahepatic Hydatid Cysts
– Endemic to Mediterranean and
sheep-raising contries
– Contact with dog feces or
contaminated food
– On CT appears as
hypoattenuating lesion with a
distinguishable wall
– Coarse calcifications of wall in
50% of cases
– Daughter cysts nearby in 75% of
patients
Abdominal CT: Differential Diagnoses
Type of Cause
Congenital Cystic
Lesions
Infective Cystic
Lesions
Neoplastic Cystic
Lesions
Disease Entity
X
X
X
X
Simple cysts
ADPLD
Bile duct harmartomas
Caroli’s disease
X
Pyogenic liver abscess
Amebic liver abcess
Hydatid cysts
Cystic liver metastases
Cystic HCC
Billiary cystadenoma
Undifferentiated embryonal sarcoma
BIDMC, PACS
X = Eliminated
Companion Patients
Some common radiologic findings of neoplastic cystic
lesions…
Companion Patient #8:
Cytic Liver Mets on CT
• Cystic Liver Mets
– Most are solid but may have
partial cyst-like appearance
– Mechanisms of seeding:
hematogenous or peritoneal
– Often with enhancement of
peripheral viable irregular
tissue
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #9:
Cystic HCC on CT
• Cystic HCC
– 70% of patients will also
show signs or complications
of liver cirrhosis
– Often with a capsule or
hypervascular solid parts
– May show vascular or biliary
invasion
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #10:
Biliary Cystadenoma on CT
• Biliary Cystadenoma
– Large range in size (1.5cm to
35 cm)
– Multilocular slow growing
lesions
– 55% in the right liver lobe
– On CT appears a solitary,
well-defined cystic mass with
a capsule and internal septa
Mortele KJ et al. Radiographics 2001; 21(4)
Companion Patient #11:
Undifferentiated Embryonal Sarcoma on CT
• Undifferentiaed Embryonal
Sarcoma
– Predominates in children or
young adults
– Pseudocapsule
– Heterogeneous enhancement
of the peripheral borders of
the mass
– Usually very large (>10 cm)
Mortele KJ et al. Radiographics 2001; 21(4)
Abdominal CT: Differential Diagnoses
Type of Cause
Congenital Cystic
Lesions
Infective Cystic
Lesions
Neoplastic Cystic
Lesions
Disease Entity
X
X
X
X
Simple cysts
ADPLD
Bile duct harmartomas
Caroli’s disease
X
Pyogenic liver abscess
Amebic liver abcess
Hydatid cysts
X
Cystic liver metastases
Cystic HCC
Billiary cystadenoma
Undifferentiated embryonal
sarcoma
BIDMC, PACS
X = Eliminated
Our Patient: Pelvic CT
“Please evaluate for infectious etiologies”
Our Patient:
Coronal Pelvic CT with Contrast
BIDMC, PACS
Our Patient:
Coronal Pelvic CT with Contrast
BIDMC, PACS
• Within the LLQ and centered in the mesenteric fat
• 4.4 x 5.4 x 5.5 cm (AP, transverse, and craniocaudal)
• Lesion with thick, irregular, enhancing rim with a low density
center. Well-defined borders.
• Supply by several feeding vessels
Our Patient:
Sagittal Pelvic CT with Contrast
Courtesy of Dr. Mortiz Kircher
• No pathologically enlarged lymph nodes in pelvis
• No free fluid
• Mass is inseparable from the jejunum?
Our Patient:
Sagittal Pelvic CT with Contrast
CT images: courtesy of Dr. Moritz Kircher
Small bowel cartoon: http://concise.britannica.com/ebc/art-53188/The-walls-of-the-hollow-organs-of-the-digestive-tract
Pelvic CT: Differential Diagnoses
Disease Entity
Adenocarcinoma of the small bowel
Lymphoma
Mesenteric fibromatosis (desmoid tumor)
Inflammatory pseudotumor
Sclerosing mesenteritis
Carcinoid
GIST
Courtesy of Dr. Mortiz Kircher
Companion Patients
Let’s consider some common radiologic findings of
these disease entities…
Companion Patient #12:
Adenocarcinoma of the Small Bowel on CT
Buckley JA et al. Radiographics 1998; 18(2)
• Adenocarcinoma of the small
bowel
– 50% are in the duodenum
– On CT manifests as:
• annular narrowing with
abrupt edges
• a discrete tumor mass
(papillary or polypoid
often)
• an ulceration
Companion Patient #13:
Lymphoma on CT
•
Buckley JA et al. Radiographics 1998; 18(2)
Lymphoma
– Primary tumor mass centered on
small bowel with appropriate
lymph node involvement
– Absence of hepatic and splenic
lesions
– Presents on CT:
• Discrete polyp within the
bowel
• Nodular filling defect within
the bowel
• Exocentric mass extending
to adjacent tissue
Companion Patient #14:
Mesenteric Fibromatosis on CT
•
Levy et al. Radiographics 2006; 26(1)
Mesenteric Fibromatosis
– Present with abdominal mass or
abdominal pain
– Looks very similar to GIST
histologically and radiologically
– May present as discrete mass or
infiltrate small bowel
– CT findings vary from
homogenous soft-tissue density
to masses with hypoattenuation
(based on histologic
composition)
– Typically no contrast
enhancement
Companion Patient #15:
Inflammatory Pseudotumor on CT
•
Levy et al. Radiographics 2006; 26(1)
Inflammatory Pseudotumor
– Often occuring in young adults
– Presenting symptoms of malaise,
weight loss, or fever
– Nonencapsulated, nodular mass
– CT findings are nonspecific:
• Heterogeneous attenuation
• Often with well-defined
margins
• Variable enhancement
pattern
• Rarely can involve small
bowel
Companion Patient #16:
Sclerosing Mesenteritis on CT
•
Levy et al. Radiographics 2006; 26(1)
Sclerosing Mesenteritis
– Tumor-like masses in the
mesentery composed of fibrosis
and chronic inflammation
– Retracts and shortens the
mesentery
– On CT:
• Well-defined or ill-defined
(variable)
• Mixed fat and soft-tissue
density
• Many with radiating strands
of fibrosis
Companion Patient #17:
Carcinoid
Levy et al. Radiographics 2006; 26(1)
Pelvic CT: Differential Diagnoses
Disease Entity
Adenocarcinoma of the small bowel
Lymphoma
Mesenteric fibromatosis (desmoid tumor)
Inflammatory pseudotumor
Sclerosing mesenteritis
Carcinoid
GIST
Courtesy of Dr. Mortiz Kircher
Putting it all together…
An Ockham’s Razor Differential
Can we find a way to relate these disparate radiologic
findings?
Our Ockham’s Razor Differentials
Disease Entity
Lymphoma
Desmoid
Carcinoid
GIST
Courtesy of Dr. Mortiz Kircher
Our patient underwent a right hepatic
lobectomy and a partial small bowel
resection
Our Patient: Surgical Pathology
• Right liver lobe
– Metastatic gastrointestinal
stromal tumor
– Multiple organizing abscesses
• Small bowel
– Malignant gastronintestinal
stromal tumor
• Invasion through muscle to
mucosa
• Rare mitotic figures
• Necrosis with blood clot
Above: Multiple mitotic centers
Below: C-KIT positive staining
– C-KIT positive
Levy et al. Radiographics 2003; 23(2)
What is Gastrointestinal Stromal
Tumor (GIST)?
GIST: An Overview
• Most common GI mesenchymal neoplasm
• Frequency between 10-20 cases per million
• Most inidividuals over 50 years old at
presentation
• Slight male predilection
• Neuro-fibromatosis type I with increased
prevalance
• 20% are malignant
GIST: An Overview
• Occurs through GI tract,
mesentery, omentum, and
retroperitoneum
• Defined by the expression
of KIT (CD117) – a tyrosine
kinase growth factor
receptor
• Usually arises in muscularis
propria of stomach or
intestinal wall
– Often presents with an
exophytic growth pattern
Anatomic Location
Stomach (70%)
Small Intestine (20-30%)
Anorectum (7%)
Colon and Esophagus (Small %)
GIST: Menu of Radiologic Tests
•
•
•
CT
– excellent for visualizing the anatomy as seen in this case study
MR
– Can be used to visualize necrosis and hemorrhage (but these factors also affect
the signal-intensity pattern)
– In general, a useful adjunct to CT as multiplanar capability can help to
determine the organ of origin in large tumors and its relation to blood vessels
US
– Excellent for biopsy
– Often used intraoperatively
• Abdominal Radiography
– Commonly used in patients presenting with signs of small intestinal
obstruction from GIST
– Reveals small intestinal dilation or soft-tissue masses
GIST: Radiologic Features
• Generally characterized by wellcircumscribed enhancing masses with central
areas of low attenuation (hemorrhage,
necrosis, or cyst formation)
• Small intestine
– Barium studies demonstrate intraluminal and
submucosal masses with sharp margins
– CT reveal intramural or intraluminal polyps.
– 22% with extraserosal locations such that small
bowel not readily evident as origin on CT.
– Often enhancing masses with centers of low
attenuation
BIDMC, PACS
GIST: Radiologic Features
• Stomach
BIDMC, PACS
– 75% occur in body of stomach
– On barium swallow have a smooth mucosal surface with features of
a submucosal mass
– On CT usually show an intramural component. Meanwhile 86%
show extragastric extension with peripheral enhancement.
Summary
In this presentation we…
• Generated a long list of differential diagnosis based upon the
various CT findings of metastatic GIST
• Used our knowledge of the anatomy of the gut wall to
recognize a mesenteric mass as extending from the small
intestine
• Further paired down our differential diagnoses by considering
and relating our radiologic findings together as a whole
• Reviewed the features of GIST, including the menu of
radiologic tests used in its diagnosis and the its typical imaging
patterns
References
Buckley JA and EK Fishman. CT Evaluation of Small Bowel Neoplasms: Spectrum of
Disease. 1998; 18:379-392.
Burkill GJC et al. Malignant Gastrointestinal Stromal Tumor: Distribution, Imaging
Features, and Pattern of Metastatic Spread. Radiology. 2003; 226(2):527-532.
Levy AD et al. From the Archives of the AFIP - Gastrointestinal Stromal Tumors:
Radiologic Features with Pathologic Correlation. Radiographics. 2003; 23(2):283-304.
Levy AD et al. From the Archives of the AFIP – Benign Fibrous Tumors and Tumorlike
Lesions of the Mesentery: Radiologic-Pathologic Correlation. Radiographics. 2006;
26:245-264
Mortele KJ et al. Cystic Focal Liver Lesions in the Adult: Differential CT and MR
imaging findings. Radiographics. 2001; 21(4):895-910.
O’Sullivan PJ et al. The Imaging Features of Gastrointestingal Stromal Tumours.
European Journal of Radiology. 2006; 60:431-438.
Sandrasegaran K et al. Gastrointestinal Stromal Tumors: CT and MRI Findings.
European Radiology. 2005; 15:1407-1414.
Acknowledgements
My sincerest thanks goes to Dr. Moritz Kircher,
who provided this case and helped to guide me
through it.
Many thanks also to:
Gillian Lieberman, MD
Jonathan Kruskal, MD
Andrew Bennett, MD
Maria Levantakis