Download Respiratory Pathology

• Non-Neoplastic Lung Diseases
The cut surface of this lung demonstrates the typical
appearance of a bronchopneumonia with areas of
tan-yellow consolidation. Remaining lung is dark red
because of marked pulmonary congestion.
Bronchopneumonia is characterized by patchy areas
of pulmonary consolidation.
•
Upon closer inspection, the pattern
of patchy distribution of a
bronchopneumonia is seen. The
consolidated areas here very closely
match the pattern of lung lobules. A
bronchopneumonia is classically a
"hospital acquired" pneumonia seen
in persons already ill from another
disease process. Typical bacterial
organisms include: Staphylococcus
aureus, Klebsiella, E. coli, and
Pseudomonas.
• A closer view of the
lobar pneumonia
demonstrates the
distinct difference
between the upper
lobe and the
consolidated lower
lobe.
Radiographically,
areas of
consolidation appear
as infiltrates.
At the left the alveoli are filled with a neutrophilic exudate that corresponds to the areas
of consolidation seen grossly with the bronchopneumonia. This contrasts with the
aerated lung on the right of this photomicrograph.
•
More virulent bacteria and/or more severe pneumonias can be associated
with destruction of lung tissue and hemorrhage. Here, alveolar walls are no
longer visible because there is early abscess formation. There is also
hemorrhage.
• Here is the gross
appearance of a lung
with tuberculosis.
Scattered tan
granulomas are
present, mostly in
the upper lung fields.
Some of the larger
granulomas have
central caseation
•
At low magnification, this photomicrograph reveals multiple granulomas.
• Seen in the pulmonary artery to
the left lung on cut section is a
large pulmonary
thromboembolus. Such
thromboemboli typically
originate in the leg veins or
pelvic veins of persons who are
immobilized. Other contributing
factors include trauma to the
extremities, hypercoagulable
states (Trousseaus's syndrome
in patients with carcinomas;
protein C or S deficiency; use of
oral contraceptives), heart
failure, pregnancy, and older
age.
• This is another
form of obstructive
lung disease
known as
bronchiectasis.
Bronchiectasis
occurs when there
is obstruction or
infection with
inflammation and
destruction of
bronchi so that
there is permanent
dilation
•
The mid lower portion of this photomicrograph demonstrates a dilated bronchus in which the
mucosa and wall is not clearly seen because of the necrotizing inflammation with destruction. This
is the microscopic appearance of bronchiectasis. Bronchiectasis is not a specific disease, but a
consequence of another disease process that destroys airways.
• The chest cavity is
opened at autopsy to
reveal numerous large
bullae apparent on the
surface of the lungs in a
patient dying with
emphysema.Bullae are
large dilated airspaces
that bulge out from
beneath the
pleura.Emphysema is
characterized by a loss of
lung parenchyma by
destruction of alveoli so
that there is permanent
dilation of airspaces.
• Microscopically at high magnification, the loss of alveolar walls with
emphysema is demonstrated. Remaining airspaces are dilated.
•
Another
gross lesion
typical for
pneumoconio
ses, and
asbestosis in
particular, is
a fibrous
pleural
plaque. Seen
here on the
pleural side
of the
diaphragmati
c leaves are
several tanwhite pleural
plaques.
•
A silicotic nodule in lung is seen here. It is composed mainly of bundles of
interlacing pink collagen. There is a minimal inflammatory reaction
• A pleural effusion
occurs when fluid
collects in the
potential space
between the
parietal pleura on
the lung and the
visceral pleura on
the chest wall. In
this case, the fluid
is red
(serosanguinous),
while the
presence of clear
fluid would be
called a serous
effusion.
• Neoplastic Lung & Pleural
Diseases
• This is a squamous cell
carcinoma of the lung
that is arising centrally
in the lung (as most
squamous cell
carcinomas do). It is
obstructing the right
main bronchus. The
neoplasm is very firm
and has a pale white to
tan cut surface.
• This is a larger squamous
cell carcinoma in which a
portion of the tumor
demonstrates central
cavitation, probably
because the tumor
outgrew its blood
supply.Squamous cell
carcinomas are one of the
more common primary
malignancies of lung and
are most often seen in
smokers.
• In this squamous cell carcinoma at the upper left is a squamous
eddy with a keratin pearl. At the right, the tumor is less differentiated
and several dark mitotic figures are seen.
• This is a peripheral
adenocarcinoma of the
lung. Adenocarcinomas
and large cell anaplastic
carcinomas tend to occur
more peripherally in lung.
Adenocarcinoma is the one
cell type of primary lung
tumor that occurs more
often in non-smokers and
in smokers who have quit.
• The glandular structures formed by this neoplasm are consistent
with a moderately differentiated adenocarcinoma. Peripheral lung
cancers that have not metastasized can be easily resected.
• This is another less
common type of
adenocarcinoma of lung
known as a
bronchioloalveolar
carcinoma. Seen here is
the multifocal variant that
appears grossly (and on
chest radiograph) as a
pneumonic consolidation.
Most of the upper lobe
toward the right has a
pale tan to grey
appearance.
•
Microscopically, the bronchioloalveolar carcinoma is composed of columnar cells that proliferate
along the framework of alveolar septae. The cells are well-differentiated. These neoplasms in
general have a better prognosis than most other primary lung cancers.
• Arising centrally in this
lung and spreading
extensively is a small cell
anaplastic (oat cell)
carcinoma. The cut
surface of this tumor has a
soft, lobulated, white to tan
appearance. The tumor
seen here has caused
obstruction of the main
bronchus to left lung so
that the distal lung is
collapsed.
• This is the microscopic pattern of a small cell anaplastic (oat
cell) carcinoma in which small dark blue cells with minimal
cytoplasm are packed together in sheets.
• Multiple variably-sized
masses are seen in all lung
fields. These tan-white
nodules are characteristic
for metastatic carcinoma.
Metastases to the lungs are
more common even than
primary lung neoplasms
simply because so many
other primary tumors can
metastasize to the lungs.
• A nest of
metastatic
infiltrating
ductal
carcinoma
from
breast is
seen in a
dilated
lymphatic
channel in
the lung.
• The dense white
encircling tumor mass
is arising from the
visceral pleura and is
a mesothelioma.
These are big bulky
tumors that can fill the
chest cavity. The risk
factor for
mesothelioma is
asbestos exposure.
•
Mesotheliomas have either spindle cells or plump rounded cells forming
gland-like configurations, as seen here microscopically. They are very
difficult to diagnose cytologically.