Chapter 15: The Lung - Pleura Flashcards
Radiation used in therapy for tumors in the lung or mediastinum often causes what type of pleuritis?
Serofibrinous pleuritis
A purulent pleural exudate (empyema) usually results from what?
Bacterial or mycotic seeding of the pleural space; by contiguous spread from intrapulmonary infections, but may also be from lymphatic or hematogenous dissemination
Which inflammatory-type of pleural effusion is characterized by loculated, yellow-green, creamy pus composed of masses of neutrophils admixed with other leukocytes?
Empyema
Empyema of the lungs may resolve, but more often the exudate organizes into what; causes what complications?
- Organizes –> dense, tough fibrous adhesions
- Frequently obliterate the pleural space or envelope the lungs
- Restricting pulmonary expansion
Which type of pleuritis is manifested by sanguineous inflammatory exudates?
Hemorrhagic pleuritis
Hemorrhagic pleuritis is found in what 3 settings?
- Hemorrhagic diatheses
- Rickettsial diseases
- Neoplastic involvement
What are the 3 major mechanisms underlying transudative pleural effusions; examples?
- ↑ hydrostatic pressure; “overflow” from the lung interstitium = CHF
- ↓ plasma oncotic pressure = nephrotic syndrome
- Movement of transudative ascitic fluid thru the diaphargam = cirrhosis
What are the 2 major mechanisms underlying exudative pleural effusions; some examples?
- Inflammation –> infection (TB, pneumonia), PE (infarction), CT disease (SLE, RA), adjacent to subdiaphragmatic disease (pancreatitis, subphrenic abscess)
- Malignancy
What is the arrow indicating on this CT scan?
Pleural effusion
How will a pleural effusion associated with mediastinal carcinomatosis appear grossly due to decreased lymph drainage?
Milky chylous effusion = Chylothorax
Noninflammatory collections of serous fluid within pleural cavities are known as what; appear how grossly?
Hydrothorax; clear fluid that is straw colored
What is the most common cause of hydrothorax; other causes?
- Most common = Cardiac failure
- Also, renal failure and cirrhosis
Hemothorax is a usually fatal complication associated with what?
Ruptured aortic aneurysm or vascular trauma
Pneumothorax is most commonly associated with what 3 conditions?
- Emphysema
- Asthma
- Tuberculosis
Spontaneous idiopathic penumothorax most often occurs in which age group and is due to what?
- Young patients
- Rupture of small, peripheral, usually apical subpleural blebs
Typical course of spontaneous idiopathic penumothorax; and likelihood or recurrence?
- Typically subsides spontaneously as air is resorbed
- Reccurent attacks = common
When injury to chest wall results in a one-way valve allowing air into the pleural space, but not out, effectively acting as a pump and ↑ pressure, this is known as?
Tension pneumothorax
A tension pneumothorax is due to expansion of which structure?
Chest wall (not lungs per se)
What is one of the more devastating consequences of Empyema that makes it hard to treat and hard to clear out?
Creating loculations –> web-like traps for fluid
What type of pneumothorax is this?
Primary pneumothorax
What type of pneumothorax is this?
Tension pneumothorax
Which type of pneumothorax is associated with pleural cavity pressure is < atmospheric pressure?
Pleural cavity pressure > atmospheric pressure?
- Pleural cavity < atmospheric = primary pneumothorax
- Pleural cavity > atmospheric = tension pneumothorax
In spontaneous idiopathic pneumothorax which direction will the trachea shift?
TOWARD the side of collapse
What is more common primary pleural tumors or secondary tumors from metastasis?
Secondary from metastasis
The most frequent metastatic malignancies of the pleura arise from which 2 sites?
Breast and lung
In most metastatic involvements of the pleura what type of effusion follows?
Serous or sero-sangioneous often containing neoplastic cells
Which soft-tissue tumor has a propensity to occur in the pleura is often attached to the surface by a pedicle?
Solitary fibrous tumor
Which immunostaining features of solitary fibrous tumors are helpful in distinguishing these tumors from malignant mesotheliomas?
CD34+ and keratin-negative
What do solitary fibrous tumors show microscopically?
Whorls of reticulin and collagen fibers w/ interspersed spindle cells resembling fibroblasts
Solitary fibrous tumors are highly associated with a cryptic inverion of which chromosome and this creates which fusion gene unique to this tumor?
Chromosome 12 —> NAB2-STAT6 fusion gene
Homozygous deletion of which tumor suppressor gene occurs in about 80% of mesothelioma; involves which chromosome?
CDKN2A/INK4-α on chromosome 9p
How does malignant mesothelioma appear grossly?
Affected lung is ensheathed by a thick layer of soft, gelatinous, grayish-pink tumor tissue
What are the 3 variants of growth that can be seen microscopically with mesothelioma?
- Epithelioid
- Sarcomatoid
- Mixed
Epithelioid type of mesothelioma resembles adenocarcinoma; how can it be differentiated via immunohistochemical stains for which 5 markers?
- (+) Keratin
- (+) Calretinin
- (+) Wilms tumor 1 (WT-1)
- (+) Cytokeratin 5/6
- (+) D2-40
The mesenchymal type of mesothelioma (sarcomatoid type) appears as what type of sarcoma and resembles?
Spindle cell sarcoma, resembling fibrosarcoma
Sarcomatoid mesotheliomas may only stain positive for which marker?
Keratin
What are the typical presenting features of malignant mesothelioma?
- Chest pain
- Dyspnea
- Recurrent pleural effusions**
Malignant mesothelioma often invades lung directly and commonly metastasizes to which LN and organs?
- Hilar LN’s
- Eventually –> liver and other distant organs
What is the prognosis of malignant mesothelioma?
50% die within 12 months; few survive longer than 2 years
What are found in increased numbers in the lungs of patients with mesothelioma?
Asbestos bodies and asbestos plaques
