Lung cancer often doesn’t cause symptoms until later stages of the disease. As lung cancer becomes more advanced, it may cause additional symptoms and complications that affect different areas of your body.

Note that just because a complication can happen, that doesn’t mean you will necessarily experience it. Your symptoms are unique to you, and your doctor can help you manage your related complications — if any occur.

Also, researchers are working on more effective treatments and prevention methods every day.

As lung cancer progresses, it can cause complications. Complications may result from the cancer spreading to other areas of your body or as a side effect of your treatment plan.

Facial swelling

Tumors around the upper area of the right lung can put pressure on the superior vena cava (SVC), a vein that transports blood from the upper body to the heart.

When this happens, it can restrict blood flow and cause swelling in the face, neck, and arms. This condition, called SVC syndrome, may need urgent treatment.

Lung function

Lung cancer causes blockages in the major airways in around 30 percent of people with advanced lung cancer.

It can also cause the buildup of fluid around the lungs, called a pleural effusion. This may result in pain and shortness of breath.

Large tumors or pleural effusions may compress the lungs, decrease lung function, and increase your risk of pneumonia.

Pneumonia symptoms include cough, chest pain, and fever. If untreated, a case of pneumonia can have life-threatening consequences.

Higher risk of infection

Persistent lung infections, like bronchitis and pneumonia, are common symptoms of lung cancer. According to research from 2019, around 50 to 70 percent of people with lung cancer contract pneumonia.

Infections may be more likely because of decreased immune system function from the cancer or from cancer treatments like chemotherapy.

Metastasis

Lung cancer can spread to other parts of the body. This spread is called metastasis. It can cause significant side effects depending on the area it spreads to. Common sites of metastasis in lung cancer are:

Tumors that are larger in size or cancer that has spread to other parts of the body indicate a more advanced stage of cancer.

Blood clots

People with lung cancer are at especially high risk of deep vein thrombosis. This occurs when a blood clot develops in a deep vein, especially the lower leg or thigh. Factors that may increase the likelihood include:

  • long-term chemotherapy with a catheter in a central vein
  • having more advanced cancer
  • older age
  • obesity
  • blood clots in other members of your family
  • sitting or lying down for extended periods

A blood clot can be life threatening if it travels to the lungs. This condition, called a pulmonary embolism, can prevent blood flow to the lungs and is one of the main causes of death in people with cancer.

Spitting up blood (hemoptysis)

People with lung cancer may also experience hemoptysis, or bloody sputum, when they cough. This may be due to bleeding in the airways or coughing causing irritation to tumors.

According to research from 2019, around 20 percent of people with lung cancer experience hemoptysis. Treatments are available to help manage cancer-related hemoptysis.

Hypercalcemia

Sometimes lung cancer can lead to increased levels of calcium in the blood, known as hypercalcemia. This may occur when your body releases a protein called parathyroid hormone-related protein. Symptoms include:

Heart blockage

Rarely, lung cancer may spread to the heart, where tumors can compress or block the veins and arteries. While there may be no symptoms at first, this spread may lead to life-threatening outcomes, such as:

Lung cancer may spread to the heart’s left atrium in up to 10 percent of cases, according to a 2019 case study. Treatment usually involves chemotherapy and radiation.

Spinal cord compression

Metastatic spinal cord compression occurs when cancer spreads to the spine and compresses or collapses the vertebrae. According to a study from 2016, around 28 percent of people with lung cancer develop this condition.

Symptoms of spinal cord compression include:

  • back pain for a long period of time
  • weakness in the legs and arms
  • having trouble walking
  • bladder dysfunction

This condition is an emergency, as compression can result in permanent damage to the spinal cord. If you have lung cancer and develop these symptoms, it’s important to seek medical treatment right away.

Esophagus complications

According to a 2015 case study, it’s rare for lung cancer to spread to the esophagus.

If lung cancer does reach the esophagus, you may have trouble swallowing or experience more pain when food passes through the esophagus on the way to your stomach.

Radiation from treating lung cancer may also cause inflammation in the esophagus, creating difficulty when swallowing.

Neuropathy

Neuropathy is a disorder that affects the nerves, mainly of the hands and feet.

Tumors located at the top of your lungs, called Pancoast tumors, can sometimes affect the nerves to your eyes and face. This can lead to Horner’s syndrome, a condition that includes:

  • a droopy eyelid on one side of the face
  • a smaller pupil in the same, affected eye
  • a lack of sweating on the same, affected side of the face

Pancoast tumors often also affect the nerves in your shoulder, causing shoulder and arm pain.

Some cancer treatments can cause nerve damage as well, resulting in symptoms such as:

Medications are available to help manage symptoms of neuropathy.

Pain with lung cancer

Pain is a common symptom of lung cancer. It can occur in the ribs or chest muscles, or in other parts of the body that lung cancer has spread to or affected. It may be worse if you laugh, take a deep breath, or cough.

Pain usually increases in more advanced stages of the disease. Treating the cancer may help with these symptoms, though treatments like surgery or chemotherapy may cause other discomfort.

Lung cancer pain can often be managed with medication and radiation.

Finding lung cancer early gives you a higher chance of treating it effectively and avoiding complications. However, lung cancer can be difficult to detect because symptoms often don’t show up until the disease is advanced.

If you’re at high risk of lung cancer, your doctor may recommend yearly screenings to check for signs of the disease.

You can also help lower your chance of developing lung cancer by not smoking or breathing in secondhand smoke.

Complications from lung cancer can occur as the disease progresses or as a result of treatment. If you notice signs of these complications, it’s important to let your doctor know.

The survival rate of people with lung cancer depends on the stage of the disease. When lung cancer is diagnosed and treated in earlier stages, people have a better chance of surviving the cancer.

Most cases of lung cancer are found at later stages because symptoms that lead to diagnosis usually don’t occur until the cancer is advanced.

More advanced and effective lung cancer treatments are being researched every day. If you have received a lung cancer diagnosis, talk with your doctor to get a better idea of your outlook.