Leading cause of lung cancer

Tobacco smoke contains substances that can injure the DNA inside lung cells. Repeated exposure may allow abnormal cells to grow and form a tumour. Second-hand smoke, radon, air pollution, and some workplace exposures can also contribute. Having an exposure does not by itself establish a diagnosis, and some people develop lung cancer without a clear avoidable cause.

Symptoms may include a cough that does not settle, breathlessness, chest discomfort, coughing blood, unexplained weight loss, or a persistent hoarse voice. A hoarse voice has many possible causes; it is a common presentation of several conditions and does not by itself identify lung cancer.

If you smoke, stopping can reduce further exposure and is worthwhile at any stage. A clinician can help with a quit plan, nicotine replacement, or other support. Arrange an assessment for persistent respiratory symptoms, especially if they change or worsen. Evaluation may involve an examination, imaging, and tests on a tissue sample when needed. If lung cancer is diagnosed, treatment choices depend on its type, stage, overall health, and tumour features; options may include surgery, radiotherapy, chemotherapy, or genomic tumour profiling.

Seek urgent medical help for coughing a substantial amount of blood, severe or rapidly worsening breathlessness, new confusion, fainting, or chest pain with sweating or weakness. Contact a clinician soon for a cough that persists, repeated chest infections, unexplained weight loss, or a hoarse voice that does not improve. These warning signs need assessment because several serious and non-cancerous conditions can cause them.

Ask whether your symptoms need imaging, which exposures may be relevant, and what support is available for stopping smoking. If a tumour is found, ask how its type and stage were established, whether genomic tumour profiling is useful, and how each proposed treatment may affect breathing, energy, and daily activities.