Respiratory Pathology Part 4 - Witrak Flashcards
What is a unilateral hilar mass until proven otherwise?
Tumor => Lung cancer
What type of lung cancer loves to cavitate?
squamous carcinoma
tumor becomes necrotic in the middle
What is the common clinical presentation of lung cancer?
- typically age >40 years in a long term smoker.
- cough, hemoptysis, chest pain, dyspnea, hoarseness.
- chest imaging (CXR, CT scan):
- mass lesion (location tendencies):
- central/bronchogenic: squamous, small cell
- peripheral: adenocarcinoma
- atelectasis or pneumonitis: from bronchial
obstruction.
- hilar/mediastinal adenopathy
- pleural/pericardial effusions.
- chest wall invasion
- in apex: Pancoast tumor with possible
Horner’s syndrome.
- in apex: Pancoast tumor with possible
- elevated diaphragm: phrenic nerve
paralysis. - superior vena cava syndrome = SVC
compression by upper mediastinal adenopathy.
- mass lesion (location tendencies):
What should you be thinking about when a smoker presents with hoarseness of the voice?
Think not only recurrent laryngeal nerve paralysis from mediastinal metastases: but also possible laryngeal cancer!
What type of cancer may mimic pneumonia and is only found after failure to respond to antibiotics?
Bronchioloalveolar Cancer
(lepidic adenocarcinoma)
Where do extrathoracic metastases most commonly present in lung cancer?
- liver
- bone: pathologic fracture may be first symptom of lung cancer
- adrenals
- brain: seizure or focal neurologic deficit may be first symptom of lung cancer
What is a paraneoplastic syndrome?
tumor associated: hormone-like compounds
or stimulation of humoral factors producing
symptoms remote from tumor
(Symptoms may precede tumor diagnosis)
What paraneoplastic syndromes are common in lung cancer?
-Hypercalcemia can be due to bone metastases or tumor production of PTHrP or calcitriol (Vitamin D): esp. squamous Ca.
-Small cell carcinoma:
- syndrome of inappropriate ADH (SIADH)
with hyponatremia.
- Cushing’s syndrome due to ACTH production.
- neurologic syndromes due to autoantibodies:
- Lambert-Eaton myasthenic syndrome.
- Cerebellar ataxia.
- carcinoid syndrome: diarrhea, flushing, cyanosis
What are the systemic effects of lung cancer?
- Heme: anemia, leukocytosis, thrombocytosis, hypercoagulability.
- Musculoskeletal: clubbing and hypertrophic osteoarthropathy, inflammatory myopathy (myositis).
What are the overall survival rates of lung cancer?
- non-small cell Ca: 15%
- small cell Ca: 5%
What type of lung cancer has the best survival rates?
Carcinoid tumors: 1-5% of all lung tumors
***10 year survival is 87% (type John Wayne had :)
What is the typical treatment for lung cancer?
- surgery for Stages I, II
- minority of patients are resectable.
- otherwise combination of chemo Rx, radiation Rx, and newer targeted therapy:EGFR inhibitors in adenocarcinoma.
What is a non-epithelial primary lung tumor?
mixtures of mesenchymal and hematopoietic types: benign and malignant.
(commonest benign tumor = “hamartoma”)
How common are metastic tumors to the lungs?
Commonest site of metastatic neoplasms: carcinomas, sarcomas, melanomas, essentially all malignancies.
- metastases typically multiple and bilateral.
- occasionally a solitary-appearing
metastasis can mimic a primary lung tumor.
What is the normal amound of pleural fluid?
Normally: no more than 15 ml of clear serous
fluid lubricates each pleural cavity.
- pleural fluid formation (mesothelial cells) =
lymphatic resorption.
What is pleural effusion?
Increased unilateral or bilateral pleural fluid causing:
- lung compression (atelectasis), chest pain
from pleuritis, dyspnea, cough, fever.
What causes pleural effusions?
- ) Increased fluid production
- ) Decreased lymphatic resorption
- ) Hemothorax = vascular rupture
What are three mechanisms that cause increased fluid production in the pleural space?
A. Non-inflammatory (transudate):
- increased hydrostatic pressure (CHF).
- decreased osmotic pressure: nephrotic syndrome.
- cirrhosis with ascites: diaphragmatic transit.
- peritoneal dialysis.
- urinothorax.
B. Inflammatory/pleuritic (exudate):
- parapneumonic: bacterial pneumonia, lung abscess, bronchiectasis, viral infection.
- empyema = grossly purulent effusion.
C. Malignant effusion (exudate): involvement of
pleural surfaces by neoplastic cells.
What is chylothorax?
Interruption of pulmonary lymphatics:
- from trauma to thoracic duct or mediastinal lymphatic blockage by malignancy
- pleural fluid triglycerides > 110 mg%.
What is the difference between the definitions of transudate vs. exudate?
Three test rule: one or more fulfilled = exudate
(1) pleural fluid protein > 2.9 gm%.
(2) pleural fluid cholesterol > 45 mg%.
(3) pleural fluid LDH > 0.45 x upper limit of normal
serum LDH.
What are the possible etiologies of increased pleural fluid?
(1) Most common causes of transudative
effusion (USA) = Left ventricular heart
failure and cirrhosis.
(2) Most common causes of exudative
effusions (USA) = bacterial pneumonia,
malignancy, viral infection, and pulmonary
embolism.
(3) Exudative fluids – require extended work-
up to determine etiology.
What are the indications for thoracentesis?
1) New effusion
- exceptions: bilateral effusions in uncomplicated heart failure or small effusions in viral pleurisy.
2) Gross appearance: pale yellow/clear vs. bloody vs. milky vs. purulent vs. brown.
- pleural fluid analysis: WBC/differential,
pH, protein, LDH, glucose.
- additional tests: amylase, cholesterol,
triglycerides, bug stains and culture/PCR,
and CYTOLOGY.
What are the three types of pneumothorax?
(1) Primary spontaneous: typically young
patients (many are smokers) - no apparent
lung disease: presumed cause = small
subpleural bleb rupture
(2) Secondary spontaneous – air leak from
underlying lung disease: emphysema,
asthma, cystic fibrosis, TB, pneumonia (esp.
pneumocystis), neoplasia; almost any
chronic lung disease.
(3) Traumatic – penetrating wound, rib fracture,
iatrogenic pleural injury, and mechanical
ventilation.
What is the clinical presentation of pneumothorax?
- dyspnea with chest pain localized to side of
pneumothorax. - physical exam for large pneumothorax:
diminished breath sounds and hyper-resonant
percussion. - arterial blood gases may be abnormal: hypoxemia and hypercarbia.
- CXR: classic features confirm diagnosis
- small, self-sealing/resorptive to large/life-
threatening: tension pneumothorax.
What are the two primary pleural tumors?
1) Solitary fibrous tumor
- usually benign/occasionally malignant tumor of submesothelial fibrous tissue.
- may be large (>10cm) and displace lung: surgery alone usually curative.
2) Malignant mesothelioma = Big Bad tumor of pleura:
- 90% related to prior asbestos exposure
- occupational vs. cases with minimal exposure.
- latent period for tumor to develop post
exposure: up to 45 years
What is the clinical presentation of malignant mesothelioma?
- Clinical symptoms: chest pain, dyspnea,
often bloody pleural effusion. - Chest imaging: unilateral/diffuse pleural
thickening often associated with effusion and
calcified pleural plaques: marker for asbestos exposure. - Histology: epithelioid (carcinoma-like) and/or
sarcomatous with invasion of chest wall and pericardium.
What is the treatment for malignant mesothelioma?
If possible, is aggressive:
-extra-pleural pneumonectomy and/or chemo Rx/radiation Rx.
What is the prognosis for malignant mesothelioma?
Usually dismal – long term survival possible only for highly selected patients tolerating radical surgery.
-overall median survival = 12 months.
What are the six congenital lung malformations?
1) Congenital pulmonary airway malformation (CPAM)
= most common congenital lung lesion
- cystic features; small risk of malignancy
- neonatal respiratory distress vs. infection vs. incidental discovery later in life.
- often pre-natal diagnosis.
2) Lung agenesis/hypoplasia
3) Tracheal/bronchial anomalies – atresia, stenosis, tracheo-esophageal fistula
4) Congenital lobar overinflation/emphysema: birth up to 6 months.
5) Foregut cysts: hilar/mediastinal – may be found incidentally: bronchogenic vs. esophageal vs. enteric.
6) Pulmonary sequestration - two types:
-Intralobar: aberrant lung tissue within a pulmonary lobe with abnormal connection to native bronchial tree: blood supply from aorta/branches; risk of recurrent infections.
-Extralobar: aberrant lung tissue located outside of normal lung: with blood supply from aorta/branches.
What are the three neonatal lung diseases?
(1) Transient tachypnea of newborn:
- late term infants: up to 72 hours.
(2) Persistent pulmonary hypertension:
- term/late term infants.
- multiple associated causes/underlying conditions.
(3) Respiratory distress syndrome (RDS) =
hyaline membrane disease: affects
premature infants: 28 weeks or less (93%)
