Most people do not experience lung cancer symptoms during early stages but may notice signs if it spreads. Potential symptoms include unexplained weight loss, general fatigue, and difficulty breathing.

Some people experience subtle symptoms of early-stage lung cancer, but these symptoms more often stem from other health issues or factors such as smoking.

Lung cancer treatment is more effective during the early stages, so it is important for people to identify symptoms and seek a diagnosis as soon as possible.

This article explains some potential early symptoms of lung cancer, risk factors, and when to see a doctor.

According to the American Cancer Society (ACS), most types of lung cancer do not cause symptoms until they spread to other areas. However, some people may experience subtle symptoms during the earlier stages of the disease.

The symptoms below usually result from another underlying cause. However, people with these symptoms should visit their doctors as a precautionary measure.

Sudden weight loss

Unexplained weight loss is a common lung cancer symptom.

A 2018 study of 3,180 adults with lung or gastrointestinal cancer found that 34.1% of the participants had already experienced weight loss by the time of diagnosis. The authors also associated weight loss before cancer treatment with lower survival rates.

Cancer can cause weight loss for many reasons, including:

Shortness of breath

Shortness of breath and wheezing are both common symptoms of lung cancer.

Some people may experience a slight cough in addition to shortness of breath. Others may have difficulty catching their breath but no cough.


A cough that does not go away after three weeks can indicate lung cancer. Some people may assume this cough is due to smoking.

The level of coughing may not always align with cancer progression. The authors of a 2018 study did not associate smoking or lung cancer stage with the severity of coughing.

A cough that produces blood may result from lung cancer or another issue with the lungs. Anyone with this symptom should see a doctor.

General fatigue

Fatigue is one of the most common symptoms of lung cancer. Lung cancer fatigue may be due to:

  • tumor development
  • anemia — a lack of red blood cells to carry oxygen
  • difficulty sleeping due to the disease
  • pain
  • malnutrition

Severe fatigue may make daily functioning harder.

Shoulder, chest, or back pain

Most people with lung cancer do not feel pain during the early stages because there are very few nerve endings in the lungs.

However, pain can occur when lung cancer invades the chest wall, ribs, vertebrae, or certain nerves. For example, Pancoast tumors, which form at the very top of the lungs, often invade nearby tissues, causing shoulder pain.

As a tumor develops, a person may begin to feel pain in their:

  • arms
  • chest
  • neck

Coughing or laughing may worsen chest pain.

Hoarse voice

A person with lung cancer or another respiratory disease may develop a hoarse, raspy voice.

This can happen if a tumor presses on the laryngeal nerve within the chest. When something compresses the nerve, it can paralyze a vocal cord, causing the voice to change.

Finger clubbing

A less typical symptom of lung cancer is finger clubbing. This causes the following changes to fingers and toes:

  • more pronounced curves
  • larger, rounded fingertips
  • curved fingernails

While lung cancer is a main cause of finger clubbing, the condition occurs in only 5% to 15% of people with lung cancer.

It is not entirely clear why finger clubbing occurs. It may be due to reduced blood oxygen levels causing tissue changes.

Horner syndrome

Pancoast tumors in the upper lungs can also cause a condition called Horner syndrome. This occurs when the tumors affect nerves that lead to the eyes or face.

Symptoms of Horner syndrome will occur in one eye or on one side of the face and may include:

If lung cancer spreads, it may cause other eye problems, including blurriness, pain, and vision loss.


Hypercalcemia occurs when there are high levels of calcium in the blood. It may be due to tumors releasing hormones that affect bone formation and calcium absorption.

Since hypercalcemia affects the entire body and can be due to other conditions, doctors may not recognize it as a lung cancer symptom initially.

Signs of hypercalcemia can include:

According to the Centers for Disease Control and Prevention (CDC), cigarette smoking is the biggest risk factor for lung cancer, accounting for 80% to 90% of lung cancer-related deaths.

When describing risk, organizations and experts may use the term “pack-year.” A pack-year is the number of cigarettes a person smokes per day each year. For example, a person with a 30-pack-year smoking history may have:

  • smoked one pack per day for 30 years
  • smoked two packs per day for 15 years

Other risk factors for lung cancer include:

  • using other tobacco products, such as cigars or pipe tobacco
  • inhaling secondhand smoke
  • exposure to radon gas
  • working with dangerous chemicals, such as:
  • living somewhere with high pollution
  • having other lung conditions, such as chronic obstructive pulmonary disease
  • having a family history of lung cancer


The U.S. Preventive Services Task Force recommends yearly lung cancer screenings for people ages 50 to 80 years who:

  • currently smoke or have quit smoking in the past 15 years
  • have at least a 20-pack-year smoking history
  • are aware of the potential benefits and harms of screening
  • can visit a facility that has experience with lung cancer screening and treatment

Screening cannot detect every instance of lung cancer, but it may lower a person’s risk of dying from the disease.

According to the CDC, people who smoke have a 15 to 30 times higher chance of dying from lung cancer than people who do not smoke.

They also highlight that, from 2013 to 2014, 1 in 4 people who did not smoke, including children, were exposed to secondhand smoke. This increases their risk of developing the disease.

Quitting smoking can reduce the risk of lung cancer regardless of age.

The symptoms above usually result from issues other than lung cancer. However, since they can indicate cancer, anyone who experiences the following issues should visit a doctor:

Often, there are no symptoms during the early stages of lung cancer.

Below are answers to some common questions about the early stages of lung cancer.

What is usually the first symptom of lung cancer?

Lung cancer usually does not show signs at first. Symptoms are most likely to appear after the cancer has spread.

Initial symptoms may include a persistent cough, chest pain, and unexplained weight loss. Lung cancer screenings may detect the disease even without symptoms.

Can someone test themselves for lung cancer?

Medical tests are necessary to find and confirm lung cancer.

Doctors may use low dose CT scans or other imaging tests to look for abnormalities in the lungs. They will confirm the diagnosis by looking at lung cells under a microscope.

Where does lung cancer usually start?

Lung cancer often starts in the alveoli (small air sacs in the lungs) or the cells inside the bronchi, the tubes that branch off from the windpipe to enter the lungs.

Other cancers may spread to the lungs from other areas of the body, but those are not lung cancer.

When do lung cancer symptoms appear?

Lung cancer symptoms typically appear after the cancer spreads. Symptoms may worsen as the disease progresses, and new symptoms, such as lymph node swelling and bone pain, may develop if the cancer moves to other parts of the body.

Lung cancer does not usually cause symptoms until it spreads. This can cause a delay in diagnosis and treatment.

However, some people experience subtle symptoms during the initial stages. Recognizing these is important because treatment is typically more effective at this stage.

Anyone with potential symptoms of lung cancer should see a doctor. In many cases, another health condition is the cause, but it is best to seek medical advice as a precaution.

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