Lecture 19 - Lung cancer

Question 1

Risk factors of lung cancer

Answer 1

Smoking
Asbestos
Radon - mining 
Occupational carcinogen - nickel
FHx

Question 2

When to screen generally

Answer 2

Disease with serious conequences
High prevalence 
Little overdiagnosis 
Detects disease before critical point
Existing treatment 
Good prognosis if treated early 
Cost effective and available

Question 3

Imaging

Answer 3

CXR 
CT
PET
MRI
USS
Bone scan
ECHO - heart

Question 4

Investigations

Answer 4

Bronchoscopy - can also do tissue biopsy

USS - nodes, lung and chest wall mass, pleural fluid, liver

CT

• Lung and pleura
• CT guided fine needle aspiration

Surgical - mediastinoscopy

Question 5

Symptoms

Answer 5

Cough 
Weight loss
Haemoptysis
Chest pain
Dyspnoea - not everyone
Wheezing 
Lung infections 
Malaise

Horseness of voice - pancoast tumour

Question 6

Signs

Answer 6

cachexia - weakness and wasting of muscles

Pale conjunctiva
Horner's syndrome 
Consolidation
Pleural effusion
Clubbing

Question 7

Effects of lung cancer

Answer 7

Endocrine

• hypercalcaemia
• Cushing’s syndrome
• SIADH

Neurological:

• encephalopathy
• peripheral neuropathy
• pancoast syndrome

Haematological

• anaemia
• thrombocytosis

Cutaneous:
- dermatomyositis

Skeletal
- finger clubbing

Question 8

Types of lung cancer

Answer 8

Small cell carcinoma
Non small cell carcinoma:
- Squamous cell carcinoma from squamous cells that produce keratin
- Adenocarcinoma from glandular structures that secrete mucin
- carcinoid tumours from mature neuroendocrine cells
- large cell carcinomas - lack squamous or glandular differentiation

Question 9

Small cell carcinoma

Answer 9

Less common
Occurs in the main bronchi and spreads
From small immature neuroendocrine cells
Aggressive and grow quickly
Higher chance of systemic spread therefore treat with chemotherapy or radiotherapy and not surgery

Question 10

Performance status

Answer 10

1. no symptoms with normal activity level
2. Symptomatic but able to carry out normal daily activities
3. Symptomatic in chair more than half the day
4. Bedridden
5. Dead

Question 11

Treatment

Answer 11

Surgery - non small cell

Radiotherapy - palliative or curative

Biological immunotherapies based on mutational analysis

Question 12

Respiratory Carcinoma

Answer 12

Uncontrolled division of epithelial cells that line the respiratory tract forming a mass

Question 13

Epithelial cells of the respiratory tract

Answer 13

Ciliated columnar cells - sweep mucous up to oropharynx
Goblet cells - secrete mucin
Basal cells - differentiate into other cells
Club cells - protect the bronchiolar epithelium
Neuroendocrine cells - secrete hormones into the blood

Question 14

Paraneoplastic syndrome

Answer 14

When a cancer secretes hormone

Small cell carcinoma can secrete

• ACTH
• ADH
• autoantibodies

Question 15

Why can small cell carcinoma cause Cushing’s syndrome

Answer 15

Paraneoplastic syndrome in which small cell carcinomas secrete ACTH which stimulates the increased release of cortisol causing Cushing’s syndrome

Question 16

Lambert-Eaton myasthenia syndrome

Answer 16

Small cell carcinoma can secrete autoantibodies which can destroy neurones

Type II sensitivity reaction

Question 17

Squamous cell carcinoma

Answer 17

Centrally located
Strongly associated with smoking
Can release PTH

Question 18

Adenocarcinomas

Answer 18

Develop peripherally in a bronchial or alveolar wall

Question 19

Pancoast tumors

Answer 19

Mass in the upper right lung (most oxygenated area)
Can damage:
- thoracic inlet 
- brachial plexus 
- cervical nerves
- sympathetic nerves (horners syndrome)

Question 20

Horners syndrome

Answer 20

• partial ptosis
• anhydrosis - dry skin
• myosis - pupil constriction

Question 21

Consequences of squamous cell carcinoma

Answer 21

Secretes PTH

Brittle bones as increased resorption of bone to increase blood calcium levels