Epidemiology
- Leading cause of cancer-related deaths in western world
- Affects 1.2 million people annually worldwide
- 40,000 cases diagnosed in the UK each year
- Results in 29,000 deaths
- Commonest malignancy in men
- Second commonest malignancy in women
- Male : female ratio = 3:2
- Overall, 5-year survival is about 6%
Aetiology
- Smoking is primary risk factor
- Responsible for 85% cases in UK
- The incidence of lung cancer is related to the number of
cigarettes smoked
- Other risk factors include
- Passive smoking
- Environmental and occupational hazards
- Diet
- Genetic factors
Pathology
Adenocarcinoma
- Accounts for 45% of all cases
- 75% cases are peripheral
- Lymph node metastases are common
Squamous cell carcinoma
- Accounts for 30% of all cases
- 70% are centrally located near the hilum or major bronchi
- Often locally invasive
Large cell tumours
- Account for 5-10% of tumours
- Usually peripherally located
- Poorly differentiated tumours may cavitate
- Early spread to distant sites
Small cell tumours
- Accounts for 20% of tumours
- 80% centrally located
- Can produce neuroendocrine hormones
- May result in paraneoplastic syndromes
- Tendency to disseminate early
Management of suspected lung cancer
- The aims of evaluating a patient with suspected lung cancer are to
determine
- Cell type of the tumour
- Anatomical extent of the disease
- Functional status of the patient
Investigation of potential lung cancer
Imaging
- Chest x-ray
- CT of chest
- Positron emission tomography
- Magnetic resonance imaging
Invasive
- Bronchoscopy
- CT-guided percutaneous needle biopsy
- Mediastinoscopy
- Left anterior mediastinoscopy
Surgical management
- Only surgery can cure non-small cell lung cancer
- Only 25% patients have resectable disease at presentation
Preoperative assessment
- Patients require assessment of
- Pulmonary function
- Cardiac status
- Nutritional and performance status
- Pulmonary complications are commonest cause of postoperative
morbidity and mortality
- Assessment of respiratory function is important
- Pulmonary function test are essential before surgery
- Full respiratory assessment includes:
- FVC and FEV1
- Estimation of transfer factor
- Postoperative lung function prediction using anatomical
equations
- Quantitative isotope perfusions scans
- FEV1 and transfer factor less than 40% places patient in
high risk group
Surgery
- Lung resection is best treatment for Stage 1 and 2 disease
- Most patients with small-cell cancer are no suitable for surgery
- Five year survival decreases with extent of disease
- Aims of surgery are complete resection and intrapulmonary
lymphatics
- Can be achieved with
- Pulmonary lobectomy
- Pneumonectomy
- Sublobar resections
- Bronchoplastic resections
- Mortality from lobectomy is 2-4%
- Mortality from pneumonectomy is 6-8%
Bibliography
Jackman D M, Johnson B E. Small-cell lung cancer.
Lancet 2005; 366: 1385-1396 Krupnick A S,
Kreisel D, Hope A et al. Recent
advances and future perspectives in the management of
lung cancer. Curr Probl Surg 2005;
42: 540-610. |