Lung Cancer
Malignant transformation of bronchial or alveolar epithelial cells, overwhelmingly driven by cumulative carcinogen exposure (chiefly smoking), produces a locally growing mass that can obstruct airways, invade neighbouring structures or spread distantly, so the clinical picture is dictated by exactly where the tumour sits and what it presses on.
In a nutshell
Cumulative carcinogen damage (chiefly smoking) transforms bronchial or alveolar epithelium into a mass that obstructs airways, invades local structures or spreads distantly. Symptoms are predictable from tumour location: central tumours obstruct and bleed, apical tumours invade the brachial plexus (Pancoast, Horner's), and some subtypes cause paraneoplastic syndromes at a distance. Staging determines whether surgery, chemoradiotherapy or systemic therapy is possible.
Classic presentation
A smoker with a persistent cough, haemoptysis, unexplained weight loss and breathlessness, sometimes with a recurrent chest infection in the same area.
Key points
- Central tumours (often squamous or small cell) obstruct the bronchus, causing cough, fixed monophonic wheeze, haemoptysis and post-obstructive pneumonia that recurs in the same place.
Educational content pending clinical review. Not medical advice.