Lung Cancer Flashcards
Describe the epidemiological distribution of lung cancer?
Most common cause of death from cancer in UK
Peak incidence at 65yrs, 3:1 male predominance
What are the main risk factors for lung cancer?
Smoking (passive)
Urban living
Occupational exposure
What are the two main classifications of lung cancer?
Small cell (20%) Non-small cell (80%)
Where do tumours tend to arise anatomically?
Main bronchi/hilum (70%)
Peripherally (30%)
What are the common types of non-small cell lung cancer?
SCC (50%)
Adenocarcinoma (20%)
Large cell anaplastic (10%)
What is the underlying pathology behind SCCs?
Arise from sq metaplasia of pseudostratified ciliated columnar epithelium
Response to smoking
Describe SCCs
Most present as obstructive lesions of bronchus leading to infection
Local spread common
Friable
Slow going, metastases occur relatively late
Describe Adenocarcinomas
Equal gender incidence, less related to smoking
Originate peripherally
Describe Large-cell anaplastic carcinomas
Not differentiated enough to be classified
Poor prognosis
Widely disseminated at diagnosis
Describe Small-cell anaplastic carcinomas (oat-cell)
Centrally located, rapidly growing
Highly malignant, often metastasised at dx
What is the underlying pathology behind small-cell anaplastic carcinomas?
Originate from bronchial epithelium
Differentiate into neuroendocrine cells, secrete
-ADH - sx of SIADH (dilutional hyponatremia, muscle weakness, cheynes-stokes, neurological sx)
-ACTH - Cushing’s
Describe Bronchoalveolar cell carcinomas
Type of adenocarcinoma (<5%)
Better prognosis
What is the prognosis for SCLCs?
Median survival
- 3 months untreated
- 18 months treated
What is ‘Eaton-Lambert’ syndrome?
Myasthenia Gravis like sx
Scapular/pelvic girdles, reduced tendon reflexes
Dry eyes, sexual impotence, neuropathy
What is Mesothelioma?
Tumour of mesothelial cells occurring in the pleura/peritoneum
Caused by asbestos
What are the typical presenting symptoms of lung cancer?
Persistent cough (80%) Haemoptysis (70%) Dyspnoea (60%) Chest pain (40%) B sx - Lethargy, anorexia, wt. loss
What are the typical presenting signs of lung cancer?
Cachexia Anaemia Clubbing HPOA (causing wrist pain) Supraclavicular/Axillary nodes Collapse/consolidation/effusion
What are the presenting signs/symptoms of metastases?
Bone tenderness Hepatomegaly Confusion Fits Focal CNS signs Cerebellar syndrome Proximal myopathy Peripheral neuropathy
What investigations are appropriate in suspected lung cancer?
FBCs (anaemia, 2o polycythaemia) LFTs (mets) U&Es (hypercalcaemia, hyponatremia) CXR Sputum/pleural fluid cytology Staging CT (head-pelvis) Biopsy (CT guided/bronchoscopy) PET scan/radionucleotide bone scan
What signs of lung cancer are present on a CXR?
Peripheral nodules Hilar enlargement Consolidation Lung collapse Pleural effusion Bony secondaries
Describe the local complications of lung cancer
Recurrent laryngeal nerve palsy Phrenic nerve palsy SVC obstruction Horner's syndrome Rib erosion Pericarditis AF
Describe recurrent laryngeal nerve palsy
Tumour compresses recurrent laryngeal nerve
Causes vocal changes (change in voice, left vocal cord paresis)
Left more susceptible
Describe phrenic nerve palsy
Compression of phrenic nerve Dyspnoea Orthopnoea Bilat worse when supine Asymptomatic if unilateral
Describe Horner’s syndrome
Caused by a tumour of the apex (Pancoast) causing compression of a sympathetic ganglion Classic triad -Miosis -Partial ptosis -Loss of hemifacial sweating
