Lung Cancer

Question 1

What is the epidemiology of lung cancer?

Answer 1

Decreasing over time but still c.350,000/yr

More common in men than women

Biggest killing cancer, 3rd largest cause of death
- Often presents really late

Question 2

What is the aetiology of lung cancer?

Answer 2

Smoking predominantly - 80-90%

Occupational remainder

• Asbestos (+smoking = 90% risk)
• Radon
• Coal related
• Petroleum production

Question 3

What are the types of lung cancer?

including pleural cancers, metastases, important genetic mutations and non-cancerous tumours

Answer 3

Non small cell - 85%:

• Squamous - 42% = bronchial carcinomas that obstruct and lead to infection; local spread common, mets late
• Adenocarcinoma -39% = from the mucous cells in the bronchi; more common in non-smokers; often mets to brain/bones
• Large cell 8% - less differentiated, met early
• Carcinoid tumours (7%)
• Pancoast tumour - a type of NSCLC defined by its location in the right or left apex of the lung - can cause a specific set of symptoms

Small cell - 15%
- Rapidly growing, met early - almost always inoperable at presentation

Epithelial growth factor R mutation

• Means can be treated with a specific type of chemo
• 15-30% of adenocarcinoma
• 6-11% of all cancers

Other

• Malignant mesothelioma**
• Lymphomas = BALTOMA – bronchus associated tissue lymphoma
• Hamartomas = non carcinoma, benign proliferation of cartilage, glandular, fat and blood vessels
• Pleural fibroma (soft tissue, mostly benign neoplasm of pleura) vs

Metastases:

Common sites for lung metastases:

• Lymph nodes
• Bone
• Brain
• Liver
• Adrenal glands

Sites where cancers metastasise from (to the lungs):

• Kidney
• Prostate
• Breast
• Bone
• Colorectal
• Cervix, ovary

Question 4

How does lung cancer present?

Answer 4

Systemic:

• Weight loss
• Anorexia
• Night sweats, fever
• Bone pain (mets)
• Finger clubbing

General features:

• Cough - 40% patients +/- haemoptysis (7%)
• SOB
• Chest pain
• (Recurrent) chest infection

Other features depending on tumour location:

• Wheeze - Monophonic = may indicate a single blockage of a large airway (i.e. by the tumour) as opposed to polyphonic wheezes of COPD/Asthma (though most patients will also have COPD)
• Dysphagia

Pancoast tumour

• Horner’s syndrome (miosis, ptosis, anhidrosis) - as invasion of sympathetic chain e.g. at T1
• Pain + weakness in hand /arm muscles - brachial plexus involvement
• Hoarse voice + bovine cough - recurrent laryngeal nerve involvement
• Facial swelling, cyanosis and dilatation of neck veins - superior vena cava obstruction

Paraneoplastic symptoms:

• c.10% of people with lung Ca, commonly
• Humoral hypercalcaemia of malignancy - secretion of PTH-related peptide (squamous cell)
• SIADH - secretion of ADH (small cell)

Question 5

Who should I refer for a 2 week wait in lung cancer?

Answer 5

SEE ONCOLOGY DECK

Question 6

How do you investigate lung cancer?

Answer 6

CXR:

• Symptomatic tumours will usually be visible; lateral views can help
• ‘coin lesion’ = solitary, round, circumscribed shadow in lung field (but not a specific sign)
• Hilar enlargement
• Pleural effusion

CT + contrast:

• For better detail +/- staging
• Can also be used to guide biopsy of peripheral lesions

Bronchoscopy:

• With biopsy for cytology
• Only useful if tumours near the hilum

PET-CT:
- For all potentially curable patients before treatment

Biopsies:

• Neck USS + biopsy of visible lymph nodes
• Non-USS guided transbronchial needle aspiration (TNBA)
• Percutaneous transthoracic needle biopsy
• Surgical biopsy

Lung function tests

Question 7

How do you stage NSCLC?

Answer 7

TNM(7) classification:

• TX - +ve cytology, no lesion seen
• T0 = no evidence of primary
• T1 = tumour <3cm
• T2 = 3-7cm +/- involving main bronchus +/- invading visceral pleura
• T3 = >7cm that directly invades chest wall +/- diaphragm +/- phrenic nerve +/- mediastinal pleura +/- parietal pericardium
• T4 = invasion of mediastinal organs e.g. oesophagus, trachea. great vessels, malignant pleural effusion etc

N

• N0 = no lymph nodes
• N1 = ipsilateral bronchopulmonary or hilar nodes
• N2 = ipsilateral mediastinal or subcarinal nodes
• N3 = contralateral mediastinal, hilar or supraclavicular nodes

M

• M0 = no mets
• M1 = mets

Question 8

How do you mange lung cancer?

Answer 8

Smoking cessation - especially those with good prognosis

Lung function tests + cardiovascular risk calculated pre-surgery for those eligible

Surgical resection:

• Treatment of choice for early stage Ca
• What is removed depends on extent and location of disease

Radiotherapy:

• For all patients not suitable for surgery
• Can be used in palliative settings for symptom control

Chemotherapy:

• Wide variety of drugs e.g. vinblastine, carboplatin, docetaxel etc in a variety of regimens
• Some specific agents better for specific types of cancers e.g. Erlotinib for EGFR-TK mutation
• Mutlidrug regimens are standard for SCLC which is usually inoperable

Palliative care = commonly used as 5.5% 10yr survival rates even with treatment…

Question 9

What are the key features of mesothelioma?

Answer 9

Predominantly caused by asbestos exposure:

• Often those who manufactured it
• Blue fibres** - lodge in lungs, aren’t removed, cause inflammation, effects exacerbated by smoking
• Takes 20-50yrs to present - >75yrs = most common

Presents in a similar way to lung Ca:

• Dyspnoea
• Chest pain
• Weight loss, anorexia
• Fever, night sweats
• Finger clubbing
• Pleural effusion, ascites

CXR + CT:

• Pleural thickening or mass
• Rib destruction
• Pleural effusions (drain + cytology)
• CT guided biopsy

Treated with:

• Limited role for surgery
• Platinum based chemo
• Possible radiotherapy

Needs referring to HM coroner; patients may be entitled to compensation
- People generally live 1-2yrs post Dx