Lung Cancer Symptoms: Early Signs, Causes & Diagnosis

Quick Glance: Common Lung Cancer Symptoms

The most common symptoms associated with lung cancer include:

A cough that does not go away or becomes worse over time
Coughing up blood or blood-stained phlegm
Persistent shortness of breath or difficulty breathing
Chest pain or discomfort, particularly when coughing or taking a deep breath
Repeated chest infections, such as bronchitis or pneumonia
Unexplained weight loss or reduced appetite
Persistent tiredness or weakness
New or persistent wheezing or a hoarse voice

Symptoms of Lung Cancer That Should Not Be Ignored

Lung cancer symptoms that persist, recur without a clear explanation or gradually become worse should not be ignored. These may include:

Symptom	What It May Indicate
A cough lasting more than a few weeks or a long-standing cough that suddenly worsens	Irritation or obstruction of the airways.
Coughing up blood	Bleeding from the airways or lung tissue
Persistent breathlessness	Reduced airflow or impaired lung function.
Chest pain that persists or worsens	Involvement of structures around the lungs or chest wall.
Repeated bronchitis or pneumonia	Recurrent airway blockage or impaired drainage.
Unexplained weight loss and loss of appetite	Effects of cancer on the body's metabolism or reduced food intake.
Persistent hoarseness	Irritation or involvement of nerves controlling the voice box.
Swelling of the face, neck or upper chest	Pressure or blockage affecting major blood vessels.

Why Do Lung Cancer Symptoms Occur?

Lung cancer symptoms develop when abnormal cells grow in the lung tissue or airways and interfere with normal lung function. The lungs contain branching airways, including the bronchi and bronchioles, which carry air into the alveoli, where oxygen enters the blood and carbon dioxide is removed.

A tumour growing in or near an airway can irritate the airway lining or partially block the flow of air. This may lead to a persistent cough, wheezing, breathlessness or repeated chest infections. If the tumour affects tissues surrounding the lungs or chest wall, it may cause chest, shoulder or back pain.

Coughing up blood, medically known as haemoptysis, can occur when abnormal tissue or a tumour damages small blood vessels in the airways. Even a small amount of blood in sputum should be medically assessed rather than assumed to be caused by lung cancer or another specific condition.

As lung cancer progresses, symptoms may also occur outside the lungs. If cancer cells spread to the bones, a person may experience persistent bone or back pain. If it spreads to the brain, it may cause headaches or other neurological symptoms. Loss of appetite, unexplained weight loss and tiredness can occur as the body's metabolism and overall health are affected.

Symptoms of Lung Cancer That Require Immediate Medical Attention

Seek urgent medical care if you experience the following symptoms of lung cancer:

Coughing up a large amount of blood or bleeding that does not stop
Severe or rapidly worsening difficulty breathing
Sudden severe chest pain, particularly with significant breathlessness
New confusion, loss of consciousness or a seizure
Sudden weakness, difficulty speaking or other severe neurological symptoms
Rapid swelling of the face, neck or upper chest, especially with breathing difficulty
Severe symptoms caused by suspected spread to the brain or spinal cord

These symptoms can have several possible causes and do not automatically indicate lung cancer. However, they may represent a medical emergency and should be assessed without delay.

Symptoms of Lung Cancer Based on Type

The type of lung cancer cannot be identified from symptoms alone and requires medical investigations and tissue testing when appropriate. The table below presents the symptoms of different types of lung cancers.

Type	Symptoms
Non-small cell lung cancer (NSCLC)	Persistent or worsening cough; coughing up blood; breathlessness; chest pain; wheezing; hoarseness; recurrent chest infections; unexplained weight loss; tiredness.
Small cell lung cancer (SCLC)	Persistent cough; coughing up blood; breathlessness; chest pain or discomfort; wheezing; hoarseness; fatigue; loss of appetite; unexplained weight loss; facial or neck swelling.
Adenocarcinoma (a type of NSCLC)	Cough; breathlessness; chest discomfort; fatigue; unexplained weight loss; symptoms may be absent in early disease.
Squamous cell carcinoma (a type of NSCLC)	Persistent cough; coughing up blood; chest pain; breathlessness; recurrent respiratory infections.
Large cell carcinoma (a type of NSCLC)	Cough; breathlessness; chest pain; weight loss; fatigue; symptoms related to tumour growth or spread.

Symptoms of Lung Cancer-Specific Conditions

The table below presents the lung cancer-specific conditions and their symptoms:

Condition	Symptoms
Lung cancer spread to the bones	Persistent bone pain (especially in the back, hips or ribs), fractures, or reduced mobility.
Lung cancer spread to the brain	Headaches, seizures, confusion, dizziness, weakness, vision changes or other neurological symptoms.
Lung cancer spread to the liver	Loss of appetite, abdominal discomfort or swelling, jaundice, and unexplained weight loss.
Lung cancer spread to the lymph nodes	Swollen lymph nodes, particularly around the neck or above the collarbone.
Compression of chest structures	Swelling of the face, neck or upper chest, difficulty breathing, or visible enlarged veins due to compression of major blood vessels (superior vena cava syndrome).
Paraneoplastic syndromes	Weakness, confusion, muscle problems, or symptoms related to hormone or electrolyte imbalances, such as low blood sodium levels. These may occur before or alongside other lung cancer symptoms.

Can You Have Lung Cancer Without Symptoms?

Yes. Lung cancer can develop without obvious symptoms, particularly in its early stages. Some people may have no noticeable changes until the cancer becomes larger or affects nearby structures.

In some cases, lung cancer is discovered incidentally when a person has a chest X-ray, CT scan or another imaging test for an unrelated reason. This is one of the reasons why symptoms alone cannot be used to diagnose lung cancer.

People at increased risk may be offered lung cancer screening programmes depending on their age, smoking history and local healthcare recommendations. Screening is intended for people who meet specific eligibility criteria and is different from investigating symptoms.

When Can Lung Cancer Symptoms Become Life-Threatening?

Certain complications associated with lung cancer can become medical emergencies. These may include:

Symptoms	What It May Indicate
Severe breathing difficulty	A large tumour, airway obstruction, fluid around the lungs or other complications can make breathing severely difficult.
Significant haemoptysis	Heavy or persistent coughing up of blood can interfere with breathing and requires emergency care.
Superior vena cava syndrome	A tumour can compress the superior vena cava, causing swelling of the face, neck and upper chest and potentially affecting breathing.
Brain involvement	Cancer that has spread to the brain may cause seizures, confusion, severe headaches or sudden neurological changes.
Spinal cord compression	Cancer affecting the spine can cause severe back pain, weakness, numbness or problems controlling the bladder or bowel and requires urgent assessment.
Severe chest pain or sudden breathlessness	It may indicate a serious complication or another emergency condition and should not be ignored.

How are Lung Cancer Symptoms Diagnosed?

A healthcare professional may use several investigations to diagnose lung cancer and identify the cause of persistent or concerning symptoms. These may include:

Diagnostic Test	Purpose
Medical history and physical examination	Reviews symptoms, smoking and exposure history, and checks breathing and general health.
Chest X-ray	May identify an abnormal area in the lungs that requires further investigation.
Chest CT scan	Provides more detailed images of the lungs and surrounding structures.
PET CT scan	Helps assess areas of increased metabolic activity and may be used to evaluate possible spread.
Bronchoscopy	Allows a specialist to examine the airways and, when appropriate, collect tissue or fluid samples.
Biopsy	Examines cells or tissue under a microscope to determine whether lung cancer is present and identify its type.
Sputum testing	May occasionally help examine cells coughed up from the airways, although it is not suitable for diagnosing all lung cancers.
Blood tests	Assess general health and help doctors plan further investigations; they do not usually diagnose lung cancer on their own.

Imaging tests may suggest lung cancer, but a biopsy is required to confirm the diagnosis and determine the cancer type.

FAQs

Q1. What is the first symptom of lung cancer?

Ans: There is no single first symptom of lung cancer that occurs in everyone. A persistent or worsening cough is one of the most common symptoms, but some people have no symptoms in the early stages.
Q2. Can lung cancer develop without symptoms?

Ans: Yes. Early-stage lung cancer may not cause noticeable symptoms. Some cases are found incidentally during imaging performed for another health concern.
Q3. Which lung cancer symptoms should never be ignored?

Ans: Coughing up blood, a persistent or worsening cough, ongoing breathlessness, unexplained weight loss, persistent chest pain and repeated chest infections are the common lung cancer symptoms that should never be ignored.
Q4. Are lung cancer symptoms different in men and women?

Ans: The main symptoms of lung cancer are generally similar in men and women. Both may experience persistent cough, breathlessness, chest pain, coughing up blood, fatigue and unexplained weight loss. However, individual risk factors and the way cancer is detected can vary.
Q5. What are the early warning signs of lung cancer?

Ans: Possible early warning signs of lung cancer include a change in a long-standing cough, unexplained breathlessness, chest discomfort, coughing up blood and unexplained weight loss. However, early-stage lung cancer may cause no symptoms at all.
Q6. When should I see a doctor about lung cancer symptoms?

Ans: Speak to a healthcare professional if you have a persistent cough, ongoing breathlessness, unexplained weight loss, or any other symptom that concerns you, as it could be lung cancer. Coughing up blood should always be medically assessed.
Q7. Can lung cancer symptoms vary in intensity?

Ans: Yes. Symptoms of lung cancer can range from mild to severe and may change as the condition develops. Some people have only one symptom, while others experience several symptoms at the same time.
Q8. Which symptoms of lung cancer indicate an emergency?

Ans: Lung cancer symptoms like severe difficulty breathing, significant or persistent coughing up of blood, sudden neurological symptoms, seizures, loss of consciousness, severe chest pain or rapid swelling of the face and neck require urgent medical attention.