Lung cancer is the second most common type of cancer in adults in the United States. It is also the leading cause of death from cancer.

Lung cancer treatment is much more effective when the disease is in its earlier stages. However, most people with lung cancer do not experience symptoms until the disease has spread.

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.

Below, we describe early symptoms of lung cancer, as well as 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 have spread to other areas.

However, some people experience subtle symptoms during the earlier stages of the disease.

The early lung cancer symptoms that we describe below usually result from some other cause. However, people who experience these symptoms should consider visiting their doctors as a precautionary measure.

Sudden weight loss

Weight loss without a clear explanation is a common lung cancer symptom.

A 2017 study of adults with lung or gastrointestinal cancer found that 34.1% of the participants had already experienced weight loss from their cancer when they received their diagnosis. Furthermore, weight loss before cancer treatment was linked to lower survival rates.

Cancer can cause weight loss for many reasons, including:

Shortness of breath

Shortness of breath and wheezing can also be early 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 have no cough.

Cough

A slight cough that does not go away after 2 to 3 weeks can indicate lung cancer. Some people may assume that this cough is only a result of smoking.

The level of coughing may not always be associated with cancer progression. According to a 2018 study, neither smoking nor the stage of lung cancer was linked to severity of coughing in people with lung cancer.

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

General fatigue

Fatigue is one of the most common symptoms of lung cancer.

Lung cancer fatigue may be caused by:

  • tumor development
  • anemia (a lack of red blood cells to carry oxygen)
  • trouble sleeping due to the disease
  • pain
  • malnutrition

Severe fatigue can make it difficult to function on a day-to-day level.

Shoulder, chest, or back pain

Most people with lung cancer do not feel pain or other symptoms during the early stages. This is 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 make the chest pain worse.

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, which is located within the chest. When the nerve is compressed, it can paralyze a vocal cord, causing the voice to change.

Finger clubbing

A less typical symptom of lung cancer is finger clubbing. With this condition, the fingers and toes develop the following changes:

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

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

It is not entirely clear why finger clubbing occurs. It may be a result of reduced blood oxygen levels leading to tissue changes.

Horner syndrome

Pancoast tumors in the upper lungs do not only cause shoulder pain; they can also lead to 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 is possible for it to cause other eye problems. These include blurriness, pain, and vision loss.

Hypercalcemia

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

Since hypercalcemia affects the entire body and can be caused by other conditions, it may not be recognized as a lung cancer symptom at first.

Signs of hypercalcemia can include:

In general, hypercalcemia is more common in later stages of cancer.

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

Other risk factors for lung cancer include:

  • using other tobacco products, such as cigars or pipe tobacco
  • inhaling secondhand smoke
  • being exposed to radon gas, possibly from materials within the home
  • working with dangerous chemicals, such as asbestos, arsenic, or diesel
  • living in a highly polluted area
  • having other lung conditions, such as chronic obstructive pulmonary disease
  • having a family history of lung cancer

When describing risk, organizations and experts sometimes use the term “pack-year.” A pack-year refers to the number of cigarettes smoked per day each year. So 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

The U.S. Preventive Services Task Force recommends yearly lung cancer screenings for people aged 50–80 who:

  • currently smoke or have quit smoking in the past 15 years
  • have at least a 20 pack-year smoking history
  • currently smoke and are receiving counseling to help them quit
  • 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 15–30 times higher chance of dying from lung cancer compared with people who do not.

Meanwhile, according to statistics from 2013–2014, about 1 in 4 people who do not smoke, including children, are 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 these symptoms may be signs of cancer, anyone who experiences any of the following issues should visit a doctor:

Early symptoms of lung cancer

Often, there may be no symptoms during the beginning stages of lung cancer. Still, some people will have symptoms early on. These most commonly include:

  • a persistent, worsening cough
  • chest pain
  • fatigue
  • weight loss
  • feeling short of breath

Below are answers to some common questions about lung cancer.

Are there any early detection signs of lung cancer?

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

Still, some people may have early symptoms such as persistent cough, chest pain, and unexplained weight loss. Lung cancer screenings may detect the disease even without symptoms.

How do you test yourself for lung cancer?

Medical tests are needed to find and confirm lung cancer.

Doctors may check for lung cancer using low dose CT scans or other imaging tests to look for abnormalities in the lungs. They will confirm the diagnosis by looking at cells from the lungs 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.

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

When do lung cancer symptoms appear?

Lung cancer symptoms typically appear after the cancer has spread. 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.

What are the signs of lung cancer in men vs. women?

Many lung cancer signs are similar in men and women. According to one study, men with lung cancer reported more severe coughing while women were more likely to experience diarrhea. However, both had fatigue.

There are some other differences, as well. Women tend to be diagnosed at younger ages and with more advanced lung cancer than men. They also tend to have a better outlook with lung cancer compared with men.

Lung cancer is the second most common form of cancer in the U.S. It can affect anyone. However, it is particularly prevalent among people who smoke.

Usually, lung cancer does not cause symptoms until it has spread. As a result, it is not always possible to detect lung cancer in its earliest stages.

Nonetheless, some people experience subtle symptoms during the initial stages. It is important to recognize these because treatment is typically more effective when a person receives it early.

Anyone who experiences early symptoms of lung cancer should see a doctor. In many cases, something other than cancer is the cause. Still, it is best to seek medical advice as a precaution.

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