Download epithelioid cells

Today's lecture will cover 4 concepts :1- Pleural lesion
2- Paraneoplastic syndromes
3- Nasopharyngeal carcinoma
4- Laryngeal tumors
Pleural lesions
Primary intra-pleural bacterial infections
Pleural
effusion
Pleuritis
Pneumothorax
Primary neoplasm of the pleura
Malignant
mesothelioma
Pleural effusion
Is the presence of fluid in the pleural space
Types of pleural effusion
Pleural effusion classify to different types
according to the pleural fluid
there are various methods to classify the
pleural fluid
Classification of pleural fluid
By pathophysiology
By the origin of the fluid:
Transudative pleural
effusion
Exudative pleural effusion
Serous fluid (hydrothorax)
Blood (haemothorax)
Chyle (chylothorax)
Pus (pyothorax or empyem
a)
What is the difference between
exudate and transudate ?
Exudate fluid ------ protein content greater than
2.9 gm/dl
While
Transudate fluid ----- less protein content ( less
than 2.9 gm/dl
transudative pleural effusions
** also called hydrothorax
** The most common cause is CHF , also may occur due
to cirrhosis( Liver failure ) ,Renal failure like nephrotic
syndrome ( excessive loss of protein with urine)
** Releasing of cytokines or inflammatory mediators --increasing permeability of lung capillaries --- The
excessive interstitial lung fluid pass through
the visceral pleura and accumulates in the pleural
space.
Exudative pleural effusion
Pneumonias
** there is inflammatory cells --- pleuritis --- more
dangerous --- sometimes with fibrinous , hemorhagic
and suppurative --- fibrous organization – fibrous
pleural thickening --- minimal to massive calcifications
** no inflammatory cells --- no pleuritis
*****// Hemorrhagic- Cancer ,TB, Infarcts
** four common •
causes :-
) Viral pleuritis •
2) Pulmonary infarction
1
•
3) Cancer ( lung carcinoma , mesothelioma , metastatic •
neoplasms to the lung or pleural surface )
4) Microbial invasion through either direct extension of •
a pulmonary infection or blood – borne seeding (
suppurative pleuritis or empyema )
•
Exudative pleural effusion
** less common causes :1* Autoimmune diseases like SLE , rheumatoid
arthritis and uremia
,2* as well as previous thoracic surgery
Whatever the cause ,
Transudates and serous exudates usually are
resorbed without residual effects if the cause
is controlled or remits
Classification of pleural fluid
By pathophysiology
By the origin of the fluid:
Transudative pleural
effusion
Exudative pleural effusion
Serous fluid (hydrothorax)
Blood (haemothorax)
Chyle (chylothorax)
Pus (pyothorax or empyem
a)
Hemothorax
** the collection of blood in the pleural cavity
** almost always fatal
** is a complication of a ruptured intrathoracic
aortic aneurysm / trauma
Chylothorax
** is the collection of chyle in the pleural cavity
** chyle – formed in the digestive system ,
accumulate in the lymphatic ducts , consist of
microglobules of lipids which will mix with milky
lymphatic fluid in the lymphatic ducts
** occur due to disruption or obstruction of
the thoracic duct.
Obstruction occur due to intrathoracic cancer (
primry OR SECONDARY mediastinal neoplasm
such as lymphoma )
Chylothorax
** always significant
Pneumothorax
** presence of air in the pleural sac
** occur in young , healthy , usually men without any
known pulmonary disease ( simple /spontaneous /
primary )
or as a result of thoracic /lung disorder ( secondary ) ,
emphysema , lung abscess , TB , carcinoma , asthma
** Traumatic – Penetrating injury –
** tension Pneumothorax –
Complications of pneumothorax
1) Hydropneumothorax
the presence of both air and fluid within
the pleural space surrounding the lung
2) Pyopneumothorax
The accumulation of air (or other gas) and pus in
the pleural cavity.
With prolonged collapse
Common symptoms of pleural effusion: •
Chest pain •
Ipsilateral shoulder pain – diaphragm
((At the same side ))
Non-productive cough –
Pleural lesions
Primary intra-pleural bacterial infections
Pleural
effusion
Pleuritis
Pneumothorax
Primary neoplasm of the pleura
Malignant
mesothelioma
Malignant mesothelioma
** rare cancer of mesothelial cells :-- usually arising in the parietal or visceral pleura
-- less commonly occur in the peritoneum and
pericardium
** related to occupational exposure to asbestos in
the air ( 50% of patients )
Living in proximity to an asbestos factory / asbestos
worker
** latent period for developing malignant
mesothelioma is long ( 25 to 40 years ) cuz
multiple somatic genetic events are required
for neoplastic conversion of a mesothelial cells
** asbestos ie not removed or metabolized from
the lung , the fibers remain in the body for
life
Asbestos exposure
1- P16/CDKN2A (
9p21 locus)
2- NF1 (22q12 locus )
Gathering near the
mesothelial cell layer
Generate reactive o2
species
1) Inactivation of
Tumor suppressor
genes like :-
DNA damage
ONCOgenic somatic
mutations lead to :-
2) Inactivation of p53
and RB
mesothelioma
Start as pleural fibrosis
with plaque formation
Then the affected lung is
ensheathed by firm
yellow-white sometimes
gelatinous layer of tumor
Mesothelioma microscoply /histologically
conform to one of three patterns :1) Epithelial mesothelioma :** most common pattern
** may confused with a pulmonary
adenocarcinoma
** epithelial cells turn cancerous , Once
epithelial cells become cancerous they are
called epithelioid cells , they lose uniformity
or otherwise become atypical in appearance
** Epithelioid cells occur more commonly in cases
of malignant pleural mesothelioma rather than
peritoneal
mesothelioma.
** epithelial cells lack mobility , less likely to
spread to distant locations , may spread to
nearby lymph nodes and from there migrate
locally via the lymphatic system .
** there is A certain type of epithelial
mesothelioma occurs more commonly in
women, and it’s known as well-differentiated
papillary mesothelioma ( projecting of small
papillary buds ) .
2) Sarcomatous :** sarcomatoid cells are loosely organized, and
they can migrate easily, leading to quicker
metastasis.
** cells appear elongated, spindle-shaped and
often form a fibrous pattern( fibroblastappearing cells )
** Some epithelioid cells may be present within
sarcomatoid tumors, but by definition they
must make up less than 10 percent of the
tumor’s mass .
Epitheial
- Most common pattern
- Most effective treatment
options
- slow metastasis , spread by
lymphatic
System
- less aggressive
Sarcomatous
- Least common pattern - the most resistance to cancer therapies
- quicker metastasis , spread
easily
- More aggressive
3) Biphasic
** have both sacromatous and epithelial areas
diagnosis
1- patient's medical history. A history of exposure
to asbestos may increase clinical suspicion for
mesothelioma.
2- physical examination .
3- chest X-rays may reveal pleural thickening
4- LFT
5- CT scan
6- biopsy
treatment
** poor prognosis
** Mesothelioma is generally resistant to
radiation and chemotherapy treatment -Long-term survival and cures are exceedingly
rare
** immunotherapy and surgery could be
used