Lung cancer Flashcards
Summarise the epidemiology of lung cancer
third most common cause of death in the UK
accounts for over 40,000 deaths per annum in the UK
quarter of all cancer deaths
80% of patients die within one year of diagnosis
5 year survival is 5.5%
causative factor
tobacco
radon
asbestos
Describe the statistics associated with lung cancer
Fourth most common cause of cancer
Second highest death rate from a cancer.
20% of all cancers in men with a life time risk of 1 in 13
12% of all cancers in women with a life time risk of 1 in 23.
Worldwide lung cancer incidence 1.6 million
1,095,200 cases in men
513,600 in women
724,300 new diagnoses in the developed world
884,500 new patients diagnosed with lung cancer in the developing world
Describe mutational compensation
All cells want to be immportal
pRB, p53 and box prevent this
smoking damages p53 allowing oncogenes and viruses to propel cells towards immortality- leading to cancer
smoking damages p53 genes, preventing cells undergoing apoptosis and arrest to allow them to become cancerous
What is key to remember about smoking
Stopping smoking: at any age will reduce risk
Smoking prevalence is decreasing
Describe the recent trends associated with lung cancer
Age groups 35-55- prevalence is decreasing in both sexes
55+- decreasing in both- women started to decrease
Describe the risk associated with passive smoking
Risk is greater and increases with the number of years spent living with a smoking relative
Describe the clinical presentation of lung cancer
Haemoptysis - coughing up blood unexplained or persistent (more than 3 weeks) cough chest/shoulder pain chest signs dyspnoea hoarseness finger clubbing- greater than 180 degree bend of the nails (nail becomes boggy and the angle between the nail and the nail bed becomes more obtuse) Urgent referral for a CXR
What is the choice of treatment based on
The choice of treatment is based on 3 key factors:
§ Histological cell type.
§ Stage of the lung cancer.
§ Performance status of the patient.
What is the main distinction for treatment based on
Histological cell type
The main distinction for the purposes of treatment choice is between small cell lung cancer and non-small cell lung cancer. The latter accounts for about 75% of all lung cancers and consists of squamous cell carcinoma, large cell carcinoma, anaplastic carcinoma, adenocarcinoma, bronchiolo-alveolar cell carcinoma and other rare tumour groups.
Describe the different types of lung cancer
Small cell lung cancer: highly malignant form, with shorter doubling time and earlier metastases
Non small cell lung cancer: subdivided to adenocarcinomas, squamous cell cacner or large cell cancer
Describe the epidemiology of the different types of lung cancer
§ Small cell lung cancer – ~20-25% of lung cancers.
§ Non-small cell lung cancer – ~75% of lung cancers.
o Squamous cell carcinoma – 25-40%.
o Adenocarcinoma – 25-40%.
§ Incidence on the increase (common in females
Why do we have subtypes for non-small cell lung cancers
Variety of treatments available for different tumours- we want to know their phenotype (targeted therapies)
Describe the phenotype of non-small cell lung cancers
All;
PDL-1 Status
Over 50% consider immunotherapy
Adenocarcinoma EGFR ALK gene ROS-1 kRAS
How do we determine the spread of the cancer
TMN
Describe the classifications of T
Size of tumour and where it is located
TX Primary tumor cannot be assessed, or tumor proven by presence of malignant cells in sputum or bronchial washings but not visualized by imaging or bronchoscopy
T0 No evidence of primary tumor
Tis Carcinoma in situ
T1 Tumor 3 cm or less in greatest dimension, surrounded by lung or visceral pleura, without bronchoscopic evidence of invasion more proximal than the lobar bronchus (i.e. not in main bronchus)
T2 Tumor with any of the following features of size or extent: More than 3 cm in greatest dimension. Involves main bronchus, 2 cm or more distal to the carina Invades the visceral pleura. Associated with atelectasis or obstructive pneumonitis which extends to the hilar region but does not involve the entire lung
T3 Tumor of any size that directly invades any of the following: chest wall (including superior sulcus tumors), diaphragm, mediastinal pleura, parietal pericardium; or tumor in the main bronchus less than 2 cm distal to the carina but without involvement of the carina; or associated atelectasis or obstructive pneumonitis of the entire lung
T4 Tumor of any size that invades any of the following: mediastinum, heart, great vessels, trachea, esophagus, vertebral body, carina; or tumor with a malignant pleural effusion
Regardless of size- if spread- gets upstaged
Describe the assessment of lymph spread
Consider hilar, mediastinal and contralateral lymph nodes (spread from one side to the other)
NX Regional lymph nodes cannot be assessed
N0 No regional lymph node metastasis
N1 Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes, including direct extension
N2 Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s)
N3 Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene or supraclavicular lymph node(s)
Describe metastases
MX Presence of distant metastasis cannot be assessed
M0 No distant metastasis
M1 Distant metastasis Note: M1 includes separate tumour nodule(s) in a different lobe (ipsilateral or contralateral)
Describe the progression of the tumour
T1- earliest stage
can go to M1- where the tumour has metastatic spread0 local treatment inappropriate.
Describe the relationship between diagnosis and staging
They are done together
What do we do if there are glands in lymph nodes
Biopsy- for diagnosis and assess spread for staging
What can we use for staging
radio-labelled glucose actively taken up by rapidly dividing cancer cells; lung and lymph node tissue should not take up, so if have, then cancer probably spread - activity seen on CT and can be used to see spread
FDG-PET-CT
Only imaging
No tissue diagnosis
Additional specimen collection procedure is required to confirm diagnosis
Describe Bronchoscopy & Endobronchial Ultrasound (EBUS)
Ultrasound uses vascular land marks to identify lymph nodes effected- bronchoscopy- use needle to extract tissue from lymph node for biopsy
Pathologists analyse histology and run immunological tesSmall cell carcinoma
T2bN2M0
ts to identify the tumour
Describe the use of trans-thoracic CT biopsy
Advantage: Real time Sensitivity 70-100% Disadvantage: Risk of pneumothorax (25-30%) Small sample size In case of bleeding no immediate intrabronchial treatment possible
We are penetrating lung tissue from the outside and so we can let air in
What are the use of lung function tests
Assess the fitness of the patient
Why do we need to use MRI for assessing metastases to the brain
Brain is metabolically active tissue- will have hotspots already on FDG-PET-CT- therefore MRI is needed to assess for metastatic spread
Describe small cell lung cancers
More rapidly dividing and spreading
Therefore- treatment is often chemotherapy
Describe non-small cell lung cancers
More slow growing- will try surgery with adjuvant radiotherapy or chemotherapy
Adjuvant means after surgery
What happens If the tumour has spread to the mediastinal lymph nodes
Chemotherapy and radiotherapy
If they are doing well- can try surgery
Highly advanced- can give immunotherapy
Describe the non-metastatic symptoms of cancers
metastatic symptoms- bone pain due to bone metastases
non-metastatic- cancer may be releasing pro-inflammatory molecules or PTH- resulting in low calcium
What is the issue with lung cancer
we find it quite late
prognosis is poor
tumours can spread before we see them and may have been malignant for years before we have detected them
e.g the patient may have had an adenocarcinoma for 13 years, we detect it at 15 but they die at 17- short survival time
How can we solve this issue
Regular CT screening in heavy smokers over 55- reduce death by 20%
But stopping smoking (preventative measures)- more effective
Summarise the treatment of lung cancer
Treatment Based on: Diagnosis Cell Type Subgroup Molecular Phenotype Staging Disease extent Fitness
Describe the prognosis of lung cancer
Poor prognosis
80 % die within one year
5year survival or cure rate less than 6%
Describe the survival of cancer according to stage
Survival related to suitability for surgery
considered in patients with Stage I, II & some with Stage IIIa disease
therefore, need to detect tumour early
5% overall surgical risk & 10% major complications
