5.7 Lung Cancer Flashcards
What is the leading cause of cancer death in men and women?
Lung
What does a typical lung cancer patient look like? (4)
age peak 75-90
more men than women
lower socioeconomic status
smoking history (when stopped, duration, intensity)
What % of patients with lung cancer have never smoked?
10-15%
What are other aetiological factors that could increase the risk of lung cancer? (7)
passive smoking
asbestos exposure 2x risk (plumbers, ship-builders etc)
radon (silver/uranium miners)
indoor cooking fumes (wood burning, frying fats)
chronic lung disease (COPD, fibrosis)
immunodeficiency
genetic
What are the four classes of lung cancer?
- Squamous cell carcinoma
- Adenocarcinoma
- Large cell
- Small cell
(1-3 sometimes known as non-small cell)
What % of cases of lung cancer are squamous cell carcinoma?
~30%
What % of cases of lung cancer are adenocarcinoma?
~40% - Most common
What % of cases of lung cancer are large cell lung cancer?
~15%
What % of cases of lung cancer are small cell lung cancer?
~15%
What is squamous cell carcinoma?
- previously most common
- originating from bronchial epithelium; centrally located
What is adenocarcinoma?
originating from mucus-producing glandular tissue; more peripherally located
Why was adenocarcinoma the most common type of lung cancer from the 1980’s onwards?
low tar cigarettes, inhaled more deeply/retained longer
What is large cell lung cancer?
heterogenous group, undifferentiated
What is small cell lung cancer?
originates from pulmonary neuroendocrine cells
highly malignant
Why is small cell lung cancer grouped separately?
because it often presents very differently; much more aggressive than other types
What is metaplasia?
reversible change in which one adult cell type replaced by another adult cell type; adaptive
What is dysplasia?
abnormal pattern of growth in which some of the cellular and architecture features of malignancy are present; pre-invasive stage with intact basement membrane
What are the 6 stages in model of lung cancer development?
normal epithelium hyperplasia squamous metaplasia dysplasia carcinoma in situ invasive carcinoma
Why is dysplasia an important turning point in cancer development?
turning point from reversible to irreversible
What are the 4 important oncogenes in lung cancer?
EGFR tyrosine kinase
ALK tyrosine kinase
ROS1 receptor tyrosine kinase
BRAF
Why is it important to know the oncogenes that could play a role in lung cancer?
Targeting these proteins can have therapeutic benefit
What are the 6 key symptoms of lung cancer?
cough weight loss breathlessness fatigue chest pain haemoptysis (coughing up blood) --> rare
Why can it be hard to diagnose lung cancer?
- frequently asymptomatic, lots of space for tumour to grow before symptoms develop
- patients often have pre-existing lung conditions –> similar symptoms
What are the features of advanced lung cancer/ metastatic disease?
neurological features: focal weakness, seizures, headaches, spinal cord compression (weakness in arms and legs)
bone pain
paraneoplastic syndromes: clubbing, hypercalcemia, hyponatremia, Cushing’s
Horner’s syndrome
Superior vena cava obstruction (Pemberton’s sign)
What is Horner’s syndrome?
Apical lung tumour compresses thoracic outlet, affects sympathetic supply to face
- ptosis
- myosis (constriction of pupil)
What is Pemberton’s sign?
Superior VC obstruction
causes facial swelling and redness when they lift arms up
What is the diagnostic strategy for lung cancer? (4)
establish most likely diagnosis
establish fitness for investigation and treatment
confirm diagnosis
confirm staging
Why do we establish fitness fir investigation and treatment?
Average patient very old with many comorbidities
How do we confirm staging?
Staging CT (chest and abdomen)
When is x ray used in the investigation of lung cancer?
Early, to confirm diagnosis (staging done by CT)
When is a PET scan used in the investigation of lung cancer?
To exclude occult metastases (lymph node involvement) –> look for bright scan
Why do we do CT of chest and abdomen when investigating lung cancer?
To look for mets (esp liver)
What’s the ultimate way we mage a diagnosis and confirm type of cancer?
biopsy
How do we choose what type of biopsy to confirm type of cancer?
choose method based on accessibility, availability and impact on staging
When do we do bronchoscopy?
for tumours of central airway
where tissue staging not important
When do we use endobronchial ultrasound and transbronchial-needle aspiration of mediastinal lymph nodes?
to stage mediastinum +/- achieve tissue diagnosis
When do we use CT-guided lung biopsy
to access peripheral lung tumours
What are the three options for biopsy for lung cancer?
bronchoscopy
endobronchial ultrasound and transbronchial needle aspiration
CT- guided lung biopsy
What is the criteria for lung cancer staging?
TNM
What does T stand for in lung cancer staging (TNM)?
T1-4: tumour size and loaction
What does N stand for in lung cancer staging (TNM)?
N0-3: lymph node involvement - mediastinum and beyond
What does M stand for in lung cancer staging (TNM)?
M0-1c: metastases + number
How do we determine treatment? (4)
patient fitness
cancer history
cancer stage
patient preference
What are the 5 levels of patient fitness according to WHO?
0-Asymptomatic
1- Symptomatic but completely ambulatory
2- Symptomatic <50% in bed during the day
3- Symptomatic >50% in bed but not bedbound
4- Bedbound
5- Death
What level of patient fitness, according to the WHO patient fitness level, should radical treatment be restricted to?
0-2
When is surgical resection the standard of care for lung disease?
Early stage disease
keyhole lobectomy + lymphadectomy usual approach
sublobar resection if stage 1 (<3cm)
What is an alternative to surgery for early stage lung cancer?
radical radiotherapy
stereotactic ablative body radiotherapy (SABR)
- high precision, other structures less affected
When is radical radiotherapy used instead of surgery in early stage lung cancer?
if patient has many comorbitities
What are the 3 systemic treatment options for lung cancer?
- oncogene-directed
- immunotherapy
- cytotoxic chemotherapy
When is oncogene directed drugs used?
metastatic NSCLC with mutation
When are immunotherapy drugs typically used for treatment of lung cancer?
metastatic NSCLC with no mutation and PDL1 expression>50%
When are chemotherapy drugs typically used for treatment of lung cancer?
first line for metastatic NSCLC with no mutation and PDL1> 50% and used in combination with immunotherapy
Why do we get frequent side effects with chemo?
very non specific, many other cells affected
When should palliative and supportive care be offered for lung cancer?
advanced stage disease
- look to improve QoL
- educate about disease
- lower depression scores
What are the treatment options for early stage disease? (2)
surgery
radiotherapy
–> both with curative intent
What are the treatment options for locally advanced disease (involving thoracic lymph nodes)? (2)
surgery + adjuvant chemotherapy
radiotherapy + chemotherapy +/- immunotherapy
What are the treatment options for metastatic disease? (4)
with targetable mutation (e.g. EFGR,ALK,ROS-1): tyrosine kinase inhibitor
no mutation, PDL-1 positive: immunotherapy alone
no mutation, PDL-1 negative: chemo + immunotherapy
palliative care
What are the benefits of immunotherapy?
generally well tolerated
immune related side effects in 10-15%
How does immunotherapy work?
blocks PD-L1, allows T cell killing of tumour cell
What is the prognosis of lung cancer?
only 10% live > 10 years
survival decreases with worse staging
