Download CT of thoracic esophagus

CT of thoracic esophagus:
an old but forgettable
friend
T. Presa, B. Pérez Villacastín, M.
Repollés, S. Badillo, A. Franco
Departament of Radiology
Fundación Jiménez Díaz
IMAGING FINDINGS

ANATOMY: (Figure 1)
– The thoracic esophagus is localized into the
posterior mediastinum.
– It begins at the thoracic inlet and ends at the
esophageal hiatus in the diaphragm.
– The esophagus is related along its way:
 At the front side : with the tracheobronquial tree,
great vessels, lymphatic glands and pericardium
 At the back side: with dorsal vertebra, descendent
aorta, acigus vein and thoracic duct
 At both sides: with parietal pleura
Figure 1: The normal esophagus anatomy on CT and its
connections.
AA
T
E
AV
H
DA
E: esophagus; AA: ascending aorta; DA:
descending aorta; AV: acigus vein; T:
trachea; H: heart
IMAGING FINDINGS: ANATOMY
The normal esophageal wall is usually less than
3 mm thick at CT when esophagus is distended.
 The esophagus wall has five layers (Figure 2)

– Adventitia
– Muscular (outer and inner):
 Striated fibers in the upper third
 Striated and smooth fibers in the middle third
 Smooth fibers in the lower third
– Submucosa
– Muscularis mucosae
– Mucosa (stratified squamous epithelium) (Figure 3)
Figure 2: Microscopic view of the esophagus thoracic
wall
Adventitia
Muscular
Submucosa
Muscularis
mucosae
Mucosa
Figure 3: Microscopic view of esophagogastric
transition. The esophagus mucosa with stratified
squamous epithelium is on the right side:
IMAGING FINDINGS

PATHOLOGY: for an easy approach, the esophageal pathology is split into:
– ESOPHAGEAL TUMORS
 BENIGN:
– LEIOMIOMA
– DUPLICATION CYST
 MALIGNANT;
– ADENOCARCINOMA
– LINFOMA
– INFLAMMATORY AND INFECTIOUS DISEASES:
 ESOPHAGITIS
 SCLERODERMA
– MISCELLANEUS





ACHALASIA
BARRETT ESOPHAGUS
HIATAL HERNIA
VARICES
DIVERTICULUM
– TRAUMA
– POSTSURGICAL AND POSTENDOSCOPIC FINDINGS
BENIGN TUMORS: LEIOMYOMA
The most common benign esophageal tumor.
They arise normally from the submucosal layer.
The lesion is usually asymptomatic and slow
growing; sometimes the lesion may become
large enough to cause dysphagia.
Typically the lesion is in the distal esophagus.
Imaging findings on CT:
-well defined mass with smooth borders
-low attenuated
-they can encase the esophagus
BENIGN TUMORS: DUPLICATION CYST
A
B
Esophageal
duplication
cysts are congenital
abnormalities normally
asymptomatic.
Approx. 60% are in the
lower esophagus.
CT shows (Figure 4 A, B
axial and coronal CT) an
homogeneous mass of
low attenuation with
smooth borders and
lake of enhancement
(arrow).
MALIGNANT TUMORS: ESOPHAGEAL CANCER


The esophageal cancer is the third most
common gastrointestinal malignancy
More than 90% of esophageal cancers are
(Figure 5):
–
–


Squamous cell carcinomas (more common between
the middle esophagus)
Adenocarcinoma (more frequently found in the
distal esophagus)
The staging of esophageal cancer is assessed
with the TNM system as developed by the
American Joint Committee on Cancer
The histological types of esophageal cancer
are not taken into account in the TNM system
Figure 5: Microscopic view of the two most
frequent esophageal cancers: A) adenocarcinoma;
B) squamus cell carcinoma
A
B
MALIGNANT TUMORS: ESOPHAGEAL CANCER

TNM: T (tumor stage) (Figures 6,7)
–
Depth of tumor invasion is one of the criteria used to select the
therapy:
 T1-T2: surgical resection
 T3-T4 multimodality therapy (chemotherapy or/and radiation
with/without surgery on a second time)
–
Asymmetric thickening of the esophageal wall is a primary but
nonspecific CT finding.
–
The most important role of CT in the determination of T status is
exclusion of T4 disease (the invasion of adjacent structures).
–
CT criteria for local invasion include:
 Loss of fat planes between the tumor and the adjacent structures
in the mediastinum (although it is a reliable sign because it can
also occur in cachectic patients or in patients after radiation
therapy or surgery)
 Displacement or indentation of other mediastinal structures
–
The other T status are better stage with endoscopic US
MALIGNANT TUMORS: ESOPHAGEAL CANCER
Figure 6 :Irregular esophagus wall thickening (squamus cell
carcinoma) with fat planes between the tumor and the auricle
and descending aorta preserve. A T3 tumor was demonstrated
MALIGNANT TUMORS: ESOPHAGEAL CANCER
Figure 7 :Irregular esophagus wall thickening (squamus cell
carcinoma) with lost of fat planes and indentation on the
posterior tracheal surface (T4).
MALIGNANT TUMORS: ESOPHAGEAL CANCER

TNM: N (nodal status)
–
–
It is based on the presence (N1) or absence (N0) of
involvement of periesophageal lymph nodes (Figure)
Detection of metastatic lymph nodes at CT depends on
size criteria:


–
–
(Figure 8)
Intratorathic and abdominal lymph nodes with short axis greater
than 1 cm are enlarged
Supraclavicular lymph nodes with short axis greater than 5 mm are
considered pathologic
It is important to differentiate between left gastric lymph
nodes (resectable) and celiac lymph nodes (unresectable)
Endoscopic US uses size criteria but also internal echo to
identify lymph node metastases (has been shown to be
superior in detecting regional lymph node metastases)
Figure : Regional lymph nodes in esophageal
cancer  Cervical esophagus:


– Scalene
– Internal jugular
– Upper and lower cervical
– Periesophageal
– Supraclavicular
Intrathoracic esophagus
– Upper periesophageal (above the azygos
vein)
– Subcarinal
– Lower periesophageal (below azygos vein)
Gastroesophageal junction
– Lower esophageal
– Diaphragmatic
– Opericardial
– Left gastric
MALIGNANT TUMORS: ESOPHAGEAL CANCER
Figure 8: N1 periesophageal metastatic lymph nodes located on
subcarinal (orange arrow) and aortopulmonary window (white
arrow) spaces.
MALIGNANT TUMORS: ESOPHAGEAL CANCER

TNM: M (metastases)
–
Distant metastases have been reported at initial
presentation in 20-30% of patients with esophageal cancer
–
Distant metastases are subdivided into:



M1a: metastases to cervical or celiac nodes
M1b: metastases to distant sites
But:
–
–
–
in the midthoracic esophagus cervical or celiac lymph nodes are
considered M1b
in the distal thoracic esophagus gastric lymph nodes are considered
N1
Contrast CT is the mainstay to diagnose distant metastasis
in patients with esophageal cancer because it explores the
three most common sites of distant metastases: liver, lung
and bones
MALIGNANT TUMORS: ESOPHAGEAL CANCER
TNM STAGING
T: depth of invasion of primary tumor:
Tis: in situ
T1: invades lamina propia or
submucosa
T2: invades muscularis propria
T3: invades adventitia
T4: invades adjacent structures
N: mediastinal nodes
N0: Regional nodes not involved
N1: Reginal nodes involved
M:
M0: No distant metastases
M1: distant metastases (including
nodal involvement outside
mediastinum)
Mucosa
Submucosa
Tracheal lumen
Muscularis prorpria
T1
T2
T3
T4
Adventitia
MALIGNANT TUMORS: LYMPHOMA
Esophageal lymphoma is
normally secondary to
mediastinal lymph node
infiltration. Just 1% of
primary gastrointestinal
lymphomas are located
in the esophagus
Imaging findings:
- Secondary: mediastinal
metastatic lymph nodes
that involve secondary
the esophagus witch
has thickening walls
(Figure 9:arrow)
- Primary: Submucosal
diffuse infiltration with
well sharped margins
INFLAMMATORY AND INFECTIOUS DISEASES

ESOPHAGITIS:
– Esophageal inflammation is usually localized on mucosa surface
– Etiology: (it must be evaluated in the clinical context in which it
develops)
 Infectious esophagitis: (Figure 10)
– More frequent in inmunosuppresed patients
– Candida albicans, herpes simplex virus or cytomegalorvirus
 Postirradiation esophagitis (Figure 11)
 Other: ingestion of drugs or toxic substances, nasograstric
intubation, reflux, eosinophilic esophagitis
– Imaging findings:
 diffuse thickening of the esophagus wall, submucosal edema and
mucosa enhancement
 Usually inflammatory mediastinal lymph nodes are present
INFLAMMATORY AND INFECTIOUS DISEASES :ESOPHAGITIS

Figure 10: Diffuse thickening of the esophagus wall in
axial (A) and sagital (B) view, compatible with infectius
esophagitis. The patient was inmunocompresed in
treatment for acute linfatic leucemia. Fungal infection
was demonstrated with endoscopy.
INFLAMMATORY AND INFECTIOUS DISEASES :ESOPHAGITIS
Lumen
Mucosa
Submucosa
edema

Figure 11:Postirradiation esophagitis: Diffuse
thickening of the esophagus wall, submucosal
edema and mucosa enhancement. It can also be
appreciated in the left upper lobe signs of lost of
volume .
INFLAMMATORY AND INFECTIOUS DISEASES
 SCLERODERMA:
– Systemic sclerosis is an autoimmune
disease characterized by fibrosis,
vascular alterations and autoantibodies
– Affects the skin and internal organs,
frequently esophagus and lungs
– Imaging findings: (Figure 12)
 Diffuse esophageal dilatation with narrow
wall
 Mediastinal lympn nodes and interstitial
lung disease
INFLAMMATORY AND INFECTIOUS DISEASES :SCLERODERMA
a
b
c

Figure 12: Diffuse esophageal dilatation (a)
without obstruction confirmed on a
esophagogram with barium (c). The lung
widow (b) show and interstitial disease on
the right middle and lower lobe.
MISCELLANEUS:


BARRET ESOPHAGUS
Figure 13: A) Hiatal hernia with asymmetric thickening of
the lower esophagus (arrow) B) Microscopic view with
globet cells of intestinal metaplasia (arrow)
Barret esophagus is a premalignant condition with
increase risk of adenocarcinoma development, most
likely caused in chronic reflux esophagitis.
MISCELLANEUS
 ACHALASIA (Figure 14)
– Is a motor disorder of the esophagus that
results in aperistalsis of the lower esophagus
and inadequate relaxation of the lower
esophageal sphincter
– Barium studies are usually primary done, but
CT will help in those difficult cases and in its
complications
– Imaging findings on CT:
 Moderate to marked dilatation (with air or fluid
inside) of the esophagus (mean 4 cm) with normal
wall thickness.
 In some cases may exist an abrupt narrowing to
normal caliber near gastroesophageal junction
 Around 2-7% of patients with achalasia develop
esophageal carcinoma
MISCELLANEUS: ACHALASIA
A
B
D
E

C
F
Figure 14: Achalasia: A,B,C, D: Multiplanar CT with diffuse marked
dilatation of esophagus with normal wall thickness. On barium images E
and F exists an abrupt narrowing to normal caliber near gastroesophageal
junction. Endoscopy shows that there was nor obstruction neither mucosal
lesions.
MISCELLANEUS:
A


HIATAL HERNIA
B
Protrusion of the upper part of the stomach into the thorax
through the esophageal hiatus in the diaphragm.
Types: (Figure 15)
– Sliding (95%): the gastroesophageal junction moves with the stomach
above the diaphragm (A)
– Paraesophageal (5%): part of the stomach ascends without movement
of the gastroesophageal junction. On CT we will see part of the stomach
beside the esophagus (B)
MISCELLANEUS

VARICES
(Figure 16)
–Dilated esophageal or
paraesophageal collateral vessels
–The most common cause is portal
hypertension
–Imaging findings:
 Tubular masses of soft tissue density
on periesophageal fat that enhance
after contrast administration
 Most frequent complication:
hemorrhage
MISCELLANEUS: VARICES
A
B
C
D

E
F
Figure 16: A, B: Arterial CT with irregular and exocentric esophagus wall
thickening. C, D: Portal CT with demonstrates that the wall esophagus
thickening are tubular dilated vessels (varices). E,F: Sagital and coronal
view.
MISCELLANEUS:
DIVERTICULUM
Thoracic diverticulum
(figure 17 arrow):
-Most frequently
located in the
midesophagus, near
the tracheal
bifurcation.
-Often asymptomatic.
-Imaging findings:
-Round collection
communicates
with esophagus
lumen
-It often contains
food remains
inside
TRAUMA
 PERFORATION:
– Etiology:
(Figure 18)
 55% iatrogenic
 15% spontaneous (Boerhaave syndrome)
 14% foreign body
 10% traumatic
 6% other
– Imaging findings on CT:
 Esophageal thickening
 Extraluminal air
 Periesophageal fluid
 Pleural effusion
 Extravasated oral contrast material
MISCELLANEUS: PERFORATION
A
D
B
E
C
Figure 18: Boerhaave
syndrome:
Mediastinal window (axial
A,B and sagital D):
Esophagus with diffuse
wall thickness and
absence of lumen air
into the inferior
esophagus.
Lung window (axial C and
coronal E):
neumomediastinum
and neumothorax
TRAUMA

FISTULA
– Communication of the esophagus lumen
with other thoracic structures
– Etiology: tumors, infections, trauma,
surgery or radiation
– Types:
 Tracheoesophageal fistula: free air passes
from trachea to the esophagus. It is
important to establish the size and location
of the communication (Figure 19)
 Esophageal-pleura fistula (air and fluid in
the pleural space)
 Esophageal-pericardial fistula
MISCELLANEUS: FISTULA

Figure 19: Tracheoesophageal fistula. Patient with
esophageal carcinoma (irregular esophageal wall
thickness) with an air line (fistula) that communicates
the esophagus lumen with trachea (arrrow)
POSTSURGICAL AND POSTENDOSCOPIC FINDINGS

POSTSURGICAL
– Esophageal resections are performed for
benign or malignant esophageal lesions.
– The most common procedure is esophageal
resection with stomach, colon or intestinal
tube substituted.
– The stomach is the most convenient
esophageal substitute because it has a
reliable blood supply and it is easily connected
to the remaining esophagus with a single
anastomosis; but it incurs high morbidity in
anastomotic failure and it has been frequently
related to late complications (Figure 20).
– The use of colon for esophageal replacement
is indicated when long-term patient survival is
expected.
MISCELLANEUS: POSTSURGICAL FINDINGS

Figure 20: Esophageal resection with
stomach as substitute
POSTSURGICAL AND POSTENDOSCOPIC FINDINGS
 POSENDOSCOPIC:
Esophageal stents are used:
- for malignant strictures (Figure 21)
- as palliative treatment in those
patients who cannot tolerate radiation
therapy or chemoterapy and have
advance metastatic disease or in whom
previous therapy has failed
- malignant bronchoesophageal fistulas
- in benign lesions, stents are left for a
few months in the esophagus
MISCELLANEUS:ESOPHAGEAL STENT

Figure 21: Esophageal
stent in patient with
esophageal cancer