Kidney cancer can cause several symptoms and complications, which may include shortness of breath. Shortness of breath related to kidney cancer can have several different causes.

For instance, kidney cancer may cause breathing changes if cancer spreads to the lungs. One study found that about 30 percent of people with kidney cancer have metastasis (cancer spread out of the kidneys) at the time of their diagnosis. The lungs are the most common site for kidney cancer to spread.

Kidney cancer may also cause changes that affect the respiratory system. Shortness of breath can develop from the cancer itself, complications of the cancer, or as a side effect of cancer treatment. Fortunately, many of the complications that cause shortness of breath can be treated.

In this article, we’ll discuss possible causes of shortness of breath in people with kidney cancer. We’ll also cover when it’s time to see your doctor.

As mentioned above, the lungs are the most common site of metastasis for people with kidney cancer.

Renal cell carcinoma is the most common type of kidney cancer. It can metastasize to the lungs, causing shortness of breath and other symptoms, including:

• Chronic cough
• Coughing up blood
• Chest pain
• Reduced appetite or anorexia
• Unintentional weight loss

If your healthcare provider suspects that your cancer has spread to the lungs, they’ll likely order an imaging test of your chest. Imaging tests that can detect lung metastases include:

• X-ray
• CT scan
• MRI scan
• Positron emission tomography (PET) scan

Renal cell carcinoma may cause anemia, a shortage of red blood cells. Red blood cells contain a protein called hemoglobin that carries oxygen. Anemia is common in several types of cancer.

Red blood cells deliver fresh, oxygen-filled blood to the body’s organs and tissues. When you don’t have enough red blood cells, you may feel tired and short of breath. People with anemia often appear pale or have lighter skin than they normally would and may report pain in the chest or head.

Healthy kidneys produce a hormone that triggers the bone marrow to produce red blood cells. When the kidneys can’t function properly because of cancer, it often causes a shortage of new, healthy blood cells.

Anemia can also happen if a person experiences chronic bleeding. Renal cell carcinoma often causes hematuria, or blood in the urine. Certain cancer treatments, such as chemotherapy, can also cause anemia.

If your doctor suspects anemia, they’ll likely order a blood test.

Anemia is treatable. If you’re diagnosed with anemia, your healthcare team may recommend a blood transfusion to increase your red blood cell count or medication to stimulate the bone marrow to make more red blood cells. Erythropoiesis-stimulating agents may be helpful for people receiving chemotherapy.

Some treatments for kidney cancer can cause shortness of breath. Your cancer treatment plan depends on several factors, including the cancer type, stage, and grade.

The most common treatment for renal cell carcinoma is surgery. If the cancer cells have spread to other areas of the body, you’ll likely require additional treatments.

Immunotherapy is a type of treatment that uses drugs to strengthen the immune system’s response to cancer. Some types of immunotherapy can cause a persistent cough and shortness of breath. Immunotherapy side effects usually develop weeks to months after treatment starts.

Targeted therapy uses drugs and treatments that can target certain proteins on cancer cells to prevent them from growing and multiplying. Some of these medications can also cause shortness of breath or trouble breathing.

Renal cell carcinoma may lead to a pleural effusion. The pleura is the thin membrane that lines the lungs and chest wall. A pleural effusion develops when fluid builds up in the pleural space.

The fluid buildup keeps the lungs from being able to fill up with air. This can make it feel hard to breathe.

Pleural effusion is a common early sign of kidney cancer. It can happen when cancer spreads to the lungs. To treat a pleural effusion, your healthcare team will likely recommend draining the fluid with a small tube.

Kidney cancer may increase the risk of blood clots. A blood clot is a collection of blood cells that build up and block a blood vessel. People with renal cell carcinoma may develop a blood clot in the lungs, known as a pulmonary embolism (PE).

Shortness of breath is a common sign of a PE. Other symptoms include chest pain and a fast heart rate. It’s possible to experience trouble breathing slowly over time or quickly all at once with a PE.

PE is serious and requires urgent treatment. If you’re concerned that you may have a PE, go to the emergency room right away.

People with advanced cancer may experience changes in their breathing. Late-stage cancer affects the lungs and may cause shortness of breath, irregular breathing, shallow breathing, rapid breathing, or periods of no breathing. These types of breathing changes may be a sign that a person is nearing the end of their life.

Other Causes of Shortness of Breath

There are several health conditions that can affect your breathing. Some are related to cancer, and some aren’t. Other possible causes of shortness of breath include:

• Ascites — A buildup of fluid in the abdomen limits the expansion of the thorax when breathing.
• Asthma — This chronic condition causes inflammation in the airways.
• Chronic lung conditions — Emphysema and chronic obstructive pulmonary disease (COPD) can cause trouble breathing.
• Congestive heart failure — This chronic heart condition occurs when the heart muscle is too weak to effectively pump blood.
• Infections — Pneumonia and other infections around the lungs could cause shortness of breath.
• Injury — An injury near your lungs, such as a broken rib, may make it harder to breathe.
• Medications — Medications that lower cholesterol and high blood pressure can cause shortness of breath.

When To See Your Doctor

Seek immediate medical help if you can’t breathe. If shortness of breath interferes with your ability to function throughout the day, see your healthcare provider.

It’s important to call your healthcare team anytime you develop new symptoms during your cancer journey. This is especially true with breathing problems. New symptoms could be a sign of cancer progression or a side effect of your treatment.

A kidney cancer specialist can help you determine the underlying cause of your shortness of breath and the best way to treat it.

Experiencing shortness of breath is uncomfortable and can cause feelings of worry and anxiety. It’s natural to feel panicked when you can’t breathe easily.

Consider practicing relaxation exercises. Distracting yourself with a book or a show may help a bit too.

Your oncologist may prescribe medication to make it easier to breathe. Opioid medication, such as morphine, may relieve pain caused by lung metastases. Anti-anxiety medications may also help you relax, which can make breathing easier.

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On MyKidneyCancerTeam, people share their experiences with kidney cancer, get advice, and find support from others who understand.

Have you developed shortness of breath since being diagnosed with kidney cancer? Let others know in the comments below.