Coughing up blood and lung cancer

Blood may appear as red or rusty streaks in phlegm or as a larger amount. An airway infection, forceful coughing, widened airways, or a blood clot in the lung can also be responsible. The appearance cannot confirm lung cancer or identify the source without medical evaluation.

A lung tumour can irritate or damage tissue and small blood vessels lining an airway. Bleeding can then mix with mucus and be brought up by coughing. Lung cancer can also present with a persistent or changing cough, breathlessness, chest discomfort, a hoarse voice, repeated chest infections, reduced appetite, or unexplained weight loss. These features can have non-cancer causes as well.

Clinicians first check breathing and circulation, then ask about the amount and pattern of bleeding. Assessment may include a chest examination, blood tests, chest imaging, and sometimes a camera examination of the airways with tissue sampling. If cancer is found, further tests establish its type, extent, and features that guide treatment.

Arrange urgent same-day medical care for a few spots or streaks of blood, even if they stop. Call local emergency services when there is more than a small streak, the bleeding is continuing, or you feel seriously unwell. Avoid driving yourself if you are breathless, dizzy, faint, or weak.

Record when the bleeding began, whether it was mixed with mucus, and whether there was chest pain, fever, leg swelling, a changed cough, or recent infection. Share your smoking and occupational exposure history without embarrassment, along with previous cancer diagnoses and every medicine you use. Blood thinners are particularly relevant, but do not stop prescribed medicine unless a clinician directs you.

Seek emergency help for coughing up more than a few spots or streaks, difficulty breathing, chest or upper-back pain, a very fast heartbeat, faintness, confusion, blue or grey lips, or rapidly worsening symptoms. Sudden breathlessness with chest pain or a swollen painful leg may accompany a blood clot and requires immediate attention.

People already diagnosed with lung cancer should use the same emergency threshold. Cancer treatment can also affect infection risk, blood counts, or clotting, so tell the emergency team which treatment you received and when.

Ask what the imaging shows, whether the bleeding site is known, and whether bronchoscopy or a tissue sample is needed. If lung cancer is confirmed, ask how its type and spread affect the options, whether tumour profiling could guide systemic treatment, how bleeding will be controlled, and whom to contact if it returns.