Intrathoracic Malignancy Flashcards
What cell type is a carcinoma a malignancy of?
Epithelial cells
what cell type is involved in a sarcoma?
Soft tissue or mesenchyme
What percentage of primary lung malignancies do carcinomas make up?
> 90%
What percentage of lung carcinomas are caused by smoking?
90%
What occupations put some people at a higher risk of radon exposure?
occupations like air crew, nuclear fuel plant and power station workers
What is the name given to mutations that are essential for tumour cell survival
Driver mutations
In an adenocarcinoma of the lung which mutations are common in non-smokers?
EGFR
ALK
RET
ROS1
In an adenocarcinoma of the lung, whcih mutations are common in smokers
KRAS
BRAF
List some cellular/molecular processes seen in squamous cell carcinoma.
loss of heterozygosity (LOH) of 3p and 9p.
Oncogene SOX2 amplification in 3q.
TP53 inactivation
LOH of 8p and 5q
What mutations would you see occurring in a small cell carcinoma
inactivation of TP53 and RB1 in all tumours.
RB1 mutation is a hallmark of small cell carcinoma
PTEN mutations
FGFR1 amplifications and SOX2 amplifications.
mutations in SLIT and EPHA7.
What mutation is a hallmark of small cell carcinoma?
RB1 mutation
(RB1 gene normally makes a protein called pRB which acts as a tumour suppressor.
List some common symptoms of lung cancer
progressive shortness of breath cough weight loss chest pain hoarseness increased sputum production haemoptysis paraneoplastic manifestation symptoms referable to metastases
If a tumour obstructs the airway what clinical features may occur?
Pneumonia, abscess, lobar collapse
If a tumour spreads to the pleura what clinical features may occur?
pleural effusion
if a lung tumour invades the recurrent laryngeal nerve what clinical feature may be seen?
Hoarseness
oesophageal invasion of a lung tumour may cause what?
dysphagia
phrenic nerve invasion may cause what?
diaphragm paralysis
chest wall invasion of a lung carcinoma may cause what?
Rib destruction
SVC compression by tumour may cause what?
SVC syndrome - swelling of face and upper limbs, SOB, coughing etc.
Horner syndrome may be seen when a tumour invades what? What tumours most commonly do this?
Sympathetic ganglia invasion.
Tends to be by apical (Pancoast) tumours
If a lung carcinoma affects the heart what clinical features might you see?
Pericarditis
tamponade (fluid in the pericardium builds up, resulting in compression of the heart).
Where do carcinomas of the lung tend to metastasise to?
lymph nodes, bone, brain, liver, skin, adrenal glands
What is meant by a paraneoplastic syndrome?
symptoms that occur at sites distant from a tumour or its metastasis
In what ways can cancers spread/metastasise?
- direct route
- lymphatic route
- haematogenous routes
Lung cancer cells can produce hormones ectopically - true or false?
True
ADH can be produced by lung cancer cells (syndrome of inappropriate ADH secretion) - what would it cause?
hyponatraemia - clinical manifestations are primarily neurologic due to an osmotic shift of water into brain cells causing oedema.
If you see a patient with Cushing-syndrome what may be causing it in terms of malignancy?
lung cancer cells producing ACTH
Humoral hypercalcaemia of malignancy is caused by a tumour producing what hormone ectopically?
Parathyroid hormone (PTH)
Humoral hypocalcaemia of malignancy is caused by a tumour producing what hormone ectopically?
calcitonin
What paraneoplastic disorder can small cell carcinomas of the lung cause which may present as weakness in the limbs?
Lambert-Eaton myasthenic syndrome
What is Trousseau syndrome?
a thromboembolic disorder associated with malignancy. Makes thromboembolisms more likely as it is a hypercoagulability syndrome.
What percentage of lung carcinomas are small cell and what are non-small cell?
small cell carcinomas = 13%
non-small cell carcinomas = 87%
What is an adenocarcinoma?
A malignant tumour formed from glandular structures in epithelial tissue
What is the first line therapy for non-small cell carcinomas?
surgery
What is first line therapy for small cell carcinomas?
Chemotherapy
What is the second line therapy for non-small cell lung cancers?
radiotherapy
what is the 5 year survival rate for non-small cell lung cancers TNM stages I-II
23-60%
what is the 5 year survival rate for patients with advanced lung carcinoma TNM stages III-IV?
<1%
what is the median survival time of patients diagnosed with limited small cell carcinoma?
18 months
What class of drugs may be used if a EGFR mutation is present?
tyrosine kinase inhibitors
e.g. erlotinib, gefitinib, osimertinib
What carcinogen are 90% of malignant mesotheliomas associated with exposure to?
asbestos
What cellular processes might carcinogenic substances cause?
chronic inflammation and fibrosis
what type of lung cancer might you see pleurisy and plural effusion in?
malignant mesothelioma
When taking a history of a patient with suspected malignant mesothelioma, what is a good question to ask?
Occupational history and whether they’ve had any exposure to asbestos
What is pleurodesis?
a treatment for a pleural effusion caused by a malignant mesothelioma where a sclerosing agent, e.g. sterile talc, is instilled into the plural cavity which irritates the pleura and causes fibrosis to occur so the pleura sticks together and fluid can no longer accumulate in the cavity.
What is meant by secondary lung cancer?
Where cancer cells have spread to the lungs from a cancer that started somewhere else in the body.
