INTRATHORACIC MALIGNANCIES + TB Flashcards
what is the leading cause of cancer mortality?
lung cancer
how many cases of lung cancer are caused by smoking?
> 70%
what are examples of carcinogens in cigarette smoke?
arsenic nickel cadmium chromium acetaldehyde phenol nitrous oxide formaldehyde hydrogen cyanise
outline the risk of lung cancer with passive smoking?
relative risk is 1.25 which is equivalent to smoking 1 cigarette per day
how much more likely are smokers to get lung cancer?
15-30 times more
what are some causes of lung cancer?
smoking
occupational exposure to carcinogens e.g. asbestos, chromates, chloromethyl, silica, nickel etc
radon - naturally occurs in soils and rocks
what are the signs and symptoms of lung cancer?
cough chest pain SOB wheezing haemoptysis fatigue weight loss hoarseness of voice increased sputum production dysphagia horners syndrome Superior vena cava syndrome
what causes the hoarseness of voice in lung cancer?
invasion of the tumour into the recurrent laryngeal nerve
why can lung cancer cause dysphagia?
as the tumour or lymph nodes can compress the oesophagus
what is superior vena cava syndrome?
a group of problems caused when blood flow through the superior vena cava (SVC) is slowed down - can be caused by lung cancer compressing the vessel
what are the sympotms of superior vena cava syndrome?
swelling of upper limbs, head, neck
shortness of breath or touble breathing
coughing
describe the link between horners syndrome and lung cancer?
Pancoast tumours can cause horners syndrome as it invades the sympathetic ganglia
what are the signs of horners syndrome?
miosis (constriction of the pupils), anhidrosis (lack of sweating) and ptosis (drooping of the eyelid)
why can we get diaphragm paralysis in lung cancer?
if there is invasion of the phrenic nerve
why can we get rib destruction in lung cancer?
due to chest wall invasion
what is a pancoast tumour?
a tumour at the apex of the lung
where does lung cancer typically metastasise to?
lymph nodes, bones, brain, liver, and adrenal glands
what are paraneoplastic syndromes?
a group of rare disorders caused by the presence of tumors in the body
what are the common paraneoplastic syndromes associated with lung cancer?
hypercalcaemia, cushings syndrome, hyponatremia, gynaecomastia, peripheral neuropathy, finger clubbing
Lambert-Eaton myaethenic syndrome
what are the 2 main categories of lung cancers?
non-small cell carcinoma
small cell carcinoma
which type of lung cancer is most common?
non-small cell carcinoma (specifically adenocarcinoma)
what are the 3 types of non-small cell carcinoma?
adenocarcinoma
squamous cell carcinoma
large cell carcinoma
which lung cancer is most closely associated with smoking?
squamous cell carcinoma
whats the most common type of lung cancer found in non-smokers?
adenocarcinoma
what cell type is affected in adenocarcinoma?
glandular epithelial cells
what cell type is affected in large cell carcinoma?
epithelial cells - msot often the ones on the periphery of the lungs
what cell type is affected in squamous cell carcinoma?
psuedostratified columnar colitaed epithelium mostly in the centre of the lungs
whats the difference between limited and extensive small cell carcinoma?
limited - in 1 lobe
extensive - in both
what is Lambert-Eaton myasthenic syndrome?
a condition in which the body’s immune system attacks the connections between nerves and muscles
what is the cause of Cushing’s syndrome?
too much cortisol
outline the stages of squamous cell carcinoma?
normal respiratory epithelium - pseudostratified columnar ciliated epithelium
metaplasia - replacing brochial epithelium by mature squamous epithelium caused by irritation by cigarette smoke
dysplasia - disordered cell growth, loss of normal architecture and uniformity of individual cells, increase in mutotic figures
malignancy - excessive growth of abnormal squamous cells
outline the steps of adenocarcinoma?
pneumocytes lining epthelia change from squamous cells to more cuboidal shaped cells = atypical adenomatous cell hyperplasia
eventually the tumour becomes invasive and infiltrates normal tissue. circular glandular structures form in the tissue lined by atypical columnar epithelial cells
what is atypical adenomatous hyperplasia?
a precursor of adenocarcinoma of the lung
how do we treat small cell carcinoma?
if its limited then we use radical chemo and radiotherapy
if its extensive then we give palliative chemo and radiotherapy
whats the medial survival time in small cell carcinoma?
7% reaching 5 year
how do we treat non-small cell carcinoma?
if its in stage 1 or 2 and hasnt spread to peripheral lymph nodes we do surgical resection or potentially radical radiotherpy
if its stages 3 or 4 we offer palliative chemo and radiotherapy
whats the survival rate of non-small cell carcinoma?
25% 5 year survival
what are some molecular targeted drugs for adenocarcinoma?
tyorisine kinase inhibits such as eriotinib of geftinib
ALK inhibits such as crizotnib
what is malignant mesothelioma?
a type of cancer that occurs in the mesothelium that is usually linked to asbestos
how do we diagnose lung cancer?
chest x-ray - coin lesion CT scan PET_CT scan to see where there are active cancer cells as it measures where ther eis higher glucose turnover bronchoscopy and biopsy fine needle aspirations