Lung Cancer Flashcards
Prevalence of lung cancers
3rd most common cancer
Leading cause of cancer death
Age around 75-90
Males more likely to get
10-15% of pt never smoked
Causes of lung cancer other than smoking
Asbestos-exposure to plumbers carpenters for example which increases risk by 2-
Radon-eg silver miners
Indoor cooking fumes eg wood,smoke
Chronic lung disease eg COPD/fibrosis
Air pollution
Familial/genetic
Pathogenesis
May arise from differentiated and undifferentiated cells
Interaction between inhaled carcinogens and epithelium of upper and lower airways causes DNA adducts to form (pieces of dna covalently bound to a cancer causing chemical)
Persisting dna adducts causes mutation and genomic alterations
Types of lung cancer
Squamous cell carcinoma-oginiates from bronchial epithelium,centrally located
Adenocarcinoma-originates rom mucus producing glandular tissue so more peripherally located. From low tar cigarette which are more deeply inhaled and retained
Large cell lung cancer-heterogeneous group,undifferentiated
Small cell lung cancer-originate from pulmonary neuroendocrine cells and is highly malignant
1-3 are non small cell lung cancer (NSCLC)
Oncogenes involved
EGFR tyrosine kinase-causes adenocarcinoma more so in women of Asian ethnicity and never smokers
Anaplastic lymphoma kinase (ALK) tyrosine kinase-non small cell lung cancer in younger patients and never smokers
c-ROS oncogene 1 (ROS1) receptor tyrosine kinase-non small lung cancer in younger patients and never smoked
BRAF (downstream xell cycle signal mediators)-non small cell lung cancer esp in smokers
Symptoms
Cough
Weight loss
Breathlessness
Fatigue
Chest pain
Haemoptysis
Or asymptomatic
Features of metastatic disease
Neurologist features:focal weakness,seizures,spinal chord compression
Bone pain
Paraneoplastic syndromes eg clubbing,hypercalcaemia,hyponaetraemia,cushings
Signs
Clubbing
Horners syndrome
Superior vena cava obstruction (pembertons sign)
Cachexia
Diagnostic strategy
Establish most likely diagnosis
Establish fitness for investigation and treatment
Confirm diagnosis and histology’s
Confirm stage
Lung cancer screening
Current or ex smokers aged 55-74 invited
What imaging is most useful to exclude occult metastasis
PET-CT
Biopsy
Bronchoscopy-for tumours of central and segmental airways
Endobronchial ultrasound and transbronchial needle aspiration of mediastinal lymph nodes-to stage mediastinum
Navigational bronchoscopy and robotic sronchoscopy-for peripheral lesions/nodules that aren’t amenable to
conventional bronchoscopy or ct
Ct guided lung biopsy-to access peripheral lung tumours
Staging
T1-4 tumour size and location
N0-3 lymph node involvement mediastinum and beyond
M0-1c metastasis and number
Determinant of treatment
Patient fitness
Cancer histology
Cancer stage
Patient preference
Health servuce
Patient fitness
0-asymptomatic (fully active to carry on all pre disease activity)
1-symptomatic but complete ambulatory (restricted in physical strenuous activity but able to do light or sedentary work
2-symptomatic and about >50% of waking hours (ambulatory and able to self care but can’t do work activities)
3-symptomatic confined to bed or chair >50% waking hour (limited self care)
4-completely disabled (can’t do self care,confined to bed)
5-death
Radical treatment restricted to PS0-2