Aside from post-surgical, what are the categories of ateletasis?
2) compression (fluid, tumor or air in pleural cavity)
3) contraction (dt fibrosis and scarring in lung/pleura)
4) patchy (dt loss of surfactant, not as bad as ARDS or NRDS but can go that way)
What are three common obstructions that can cause atelectasis?
1) excessive secretions (CF)
2) bronchial tumors
3) aspirated foreign bodies
What is bronchogenic cancer?
any malignant neoplasm that arises in lung tissue first (not a met)
Lung cancer is the leading cause of cancer death in who?
What percentage of all cases appear before age 40?
Approximately what percentage of lung cancer deaths are blamed on smoking?
Where can you find radioactive elements such as polonium-210, carbon-14 and potassium-40?
Besides cigarettes, what are some risk factors for developing lung cancer?
--chemical fumes (vinyl chloride)
--silver or nickel dust
--radiation exposure including radon
What is the first and commonest symptom of lung cancer?
cough that increases in intensity and intractability, possible hemoptysis
What are some signs of a larger tumor?
--loss of appetite
--loss of weight
--dyspnea on exertion
What two kinds of cancer make up over 90% of all lung cancer cases?
--small cell lung cancer (SCLC) aka OAT CELL cancer, 1/5 of cases, highly metastatic, neurosecretory granules
--non-small cell lung cancer (NSCLC) 80%, slower growing and less metastatic, three subtypes: squamous cell carcinoma (in ctr of lung), adenocarcinoma (outer part of lung), large cell undifferentiated cancer (anywhere in lung)
--mixed-->the two types grow and spread differently and so are treated differently
What is now the most frequently diagnosed type of lung cancer?
What is the relative incidence of all those kinds of cancer?
--adenocarcinoma 25-40%, 30-35%
--squamous cell carcinoma 25-40% (approx 1/3 of all)
--small cell carcinoma 20-25%
--large cell carcinoma 10-15%
Where in the lung does squamous cell cancer tend to appear?
--near the center (near the bronchi), may present earlier and have better prognosis if diagnosed early
What are some characteristics of SCC development?
--masses are gray-white with granular and "dry" surface (adenoma is mucinous)
--metaplasia-->anaplasia typical of SCC
--basal cell hyperplasia, low columnar epithelium WITHOUT CILIA
--can obstruct bronchi and cause pneumonia, atelectasis, etc
--tends to form firm, non-encapusulated, sharply circumscribed masses
--histology: keratinization (squamous "pearls" or individual cells with eos in cytoplasm) and/or intercellular bridges
--cavitation from central necrosis in 10% (most likely to cavitate = outgrow vascular system and die in middle)
What is the most common lung cancer in women and nonsmokers?
Where does adenocarcinoma appear?
at the periphery of the lung, just below the pleura causing pleural retraction and thickening on x-ray
What are the 3 P's of adenocarcinoma?
--perpheral, pigmented and puckered
--forms where lungs have been scarred, esp from knife/bullet wounds!
--most common lung cancer in nonsmokers
What the the small cells of small cell cancer look like?
--round, oval or spindle shaped
--small epithelial cells with scant cytoplasm
--ill-defined cell borders
--finely granular nuclear chromatin (salt and pepper)
--absent or inconspicuous nucleoli
--"nuclear molding is prominent"
--aka: oat cell cancer
--dark staining cells packed tight together in sheets
--usu near hilum
What can small cell cancers do?
make hormones! paraneoplastic syndromes incl:
--ectopic production of ADH-->hyponatremia due to SIADH
--histamine production-->terrible hives
Describe large cell cardinoma.
An undifferentiated malignant epithelial tumor composed of large polygonal cells iwht no evidence of glandular of squamous differentiation and lacking the cytologic features of small cell carcinoma. Cells usu have large nuclei, prominent nucleoli, and usu don't appear in sheets.
--can extend into pleural space
--can impinge on laryngeal nerve-->hoarseness
--can impinge phrenic nerve-->diaphragmatic pareiss or paralysis, unilateral or bilateral
--can block esophagus
What do you call it when a tumor gets into the brachial plexus?
Pancoast tumor syndrome, or superior sulcus syndrome
--pain/numbness/weakness of affected arm
--vertebrae and ribs may get involved
Which is more common, primary lung cancer or metastases to the lungs?
mets are more common
What are common destinations for lung cancers metastases?
brain, bones, liver, adrenals, heart
What is a carcinoid tumor?
--slow-growing usu malignant
--neuroendocrine tumor originating in cells of neuroendocrine system
--usu in the gut
--benign or malignant (according to Miller)
--5% of all lung cancers
--may obstruct bronchi
--can produce biogenic amines (neurotransmitters) esp serotonin
--carcinoid syndrome: diarrhea, facial flushing and wheezing "occurs infrequently if the carcinoid tumor is restricted to the lung only
--pronosis good: 5 year survival 85%
--cutaneous flushing, diarrhea, bronchoconstriction and right-sided cardiac valve disease
What is the most common benign tumor of the lung, accounting for 75% of all benign?
What are hamartomas made of?
fat, epithelial tissue, fibrous tissue, cartilage in disorganized growth pattern
--usu well circumscribed
Approximately how much fluid must accumulate in the lungs before an effusion is evident on a chest x-ray?
700 ml (normally have 15ml max)
What is chylothorax?
lymphatic fluid in pleural space
What is the most common cause of spontaneous pneumothorax?
rupture of blebs lying under the visceral pleura
What exposure is usually associated with mesothelioma?
How long is mesothelioma usually latent after asbestos exposure?