Lung Flashcards
Epidemiology -4
2nd most common CA in US,
most common CA death,
worldwide smoking->80% burden male, 50% burden female,
15% 5 yr OS
K-ras mutation -3
exclusive to smokers;
overall freq in NSCLC 10-30%,
predicts resistance to EGFR TKIs
EGFR mutation -3
activate pathway -> inc cell proliferation, motility, and invasion;
overall freq in NSCLC 10-15%;
reported as (+) for mutation AND specific mutation
Are K-ras and EGFR mutations mutally exclusive? -1
yes
EML4-ALK -2
fusion oncogene,
independent driver of CA cell proliferation in 4-8% NSCLC
EML4-ALK clinical features
adenocarcinoma (97%), no/light smoking hx, younger age (median 52 yrs)
Risk factors - smoking
90% of deaths due to smoking (primary and passive),
2-10% occur in never smokers (women >men),
risk dec after cessation -> 80-90% dec after 15yr,
women higher risk than men at same exposure
risk factors - other than smoking -6
radon,
XRT,
asbestos,
occupation/environment (petroleum, nickel, arsenic, vinyl chloride, etc),
diet (low beta carotene, vit e),
coexisting lung dz,
genetic predisposition (metabolism of carcinogens, nucleotide excision repair)
pathophysiology SCLC -7
13-17% of lung CA,
most aggressive if left untreated,
clear smoking relationship,
paraneoplastic sx common,
initially highly sens to chemo-XRT-
-systemic dz, 60-70% present w/ detectable mets,
death in 2-4mo w/o tx
pathophysiology NSCLC
80-87% of lung CA, slower growing, moderately sens to XRT, low sens to conventional chemo– 50% present w/ mets
NSCLC types
adenocarcinoma 37-47% - most common type in non-smokers
squamous 25-32% - better prognosis than adeno
large cell 10-18% - poorly differentiated, dx of exclusion
prevention
no known effective method of chemoprevention
smoking cessation
screening -4
prevention (smoking cessation) is preferred over screening.
risk of second primary cancer 1-2%/yr NSCLC, 2-14% SCLC
spiral CT - saves lives, catches 49% stage I, 50% false (+), expensive
CXR-no benefit
screening - national lung screening trial (NLST) -3
CXR vs low dose CT
NN to screen to prevent one death 320 in CT arm
all-cause mortality dec by 6.7% in CT
signs and sx -6
cough (most common 45-75%, more in squamous and SCLC b/c in central airway),
wt loss,
dyspnea,
chest pain,
bronchitis with hemoptysis,
horseness,
others (bone pain, wheezing, pneumonitis, pleural/pericardial effusion, dysphagia, fatigue, clubbing)
lab abnormalities -2
hypercalcemia,
heme (anemia, leukocytosis, thrombocytosis)
syndromes and paraneoplastic syndromes -13
Horner's sx, SVC sx, Pancoast's sx --- para: SIADH, ectopic Cushing's sx, hypercalcemia, Eaton-Lambert, hypertrophic pulmonary osteoarthropathy, clubbing, dermatomyositis, acanthosis nigrans, hypercoag (DVT, PE, DIC, TTP), cachexia
metastasis sites -5
lymph nodes,
brain,
bone,
liver,
adrenal glands
diagnosis
H&P–labs: (CBC, electrolytes (Ca++), LFTs, albumin ->mostly assessing mets dz)–imaging: CXR, CT, PET (for surgical candidates), MRI (if mediastinal or chest wall invasion OR if brain mets in SCLC), bone scan, location of primary tumor correlates with histology–tissue: (depends on location): sputum cytology, bronchoscopy, transthoracic needle bx, thoracentesis, IHC staining (distinguishes mesothelioma vs lung adenocarcinoma)– other testing: PFTs (surgical eligibility), BMBx if indx
diagnosis – molecular studies and biomarkers
only send in non-squamous UNLESS never smokers OR small bx specimen
EGFR, EML4-ALK, ROS1, K-ras, ERCC1, RRM1 predict response
staging SCLC -2
limited stage (30-40%) one hemithorax, regional LN contained in a single radiation port
extensive stage (60-70%) everything else
staging NSCLC -4
TNM predicts survival
T: size, invasiveness
N: location of nodal mets-worse opposite side of body OR far reaching on same side such as supraclvicular nodes
M:
