When renal cell carcinoma (RCC) — the most common type of kidney cancer — spreads to other parts of the body, the lungs are one of the most frequent sites. Research shows that about one-third of people with kidney cancer have metastases (cancer that has spread) at the time of diagnosis. In addition, 20 percent to 30 percent of people with early-stage RCC who undergo curative surgery may develop metastases during follow-up care. Among these, the lungs are the most common site of metastasis.

When cancer that starts somewhere else in the body spreads to the lungs, it’s called lung metastasis. In this article, we’ll explain what happens when stage 4 kidney cancer spreads to the lungs, including symptoms to watch for and the treatment options that may help.

Lung Metastases After Kidney Cancer Treatment

Even if you had surgery to remove the kidney tumor or the entire kidney that contained the tumor, cancer can still come back later. This type of surgery may be a partial nephrectomy, where only the tumor and a small margin of healthy tissue are removed, or a radical nephrectomy, where the entire kidney is taken out.

Lung metastases can appear months or even years after your initial kidney cancer diagnosis. The risk of metastasis is highest in the months after treatment. However, some studies have reported cases of lung metastases happening as long as 16 years after kidney removal surgery.

Doctors often find lung metastases during routine follow-up scans. That’s why it’s crucial to attend all scheduled follow-up appointments after treatment: so your doctor can check whether the cancer has returned or spread. Follow-up visits may be more frequent at first, often occurring every few months. If no signs of cancer are found over time, your doctor may recommend appointments just once a year.

Risk Factors for Lung Metastases in Renal Cell Carcinoma

Not everyone with RCC will develop lung metastases, but certain factors can raise the risk. People with larger kidney tumors, cancer in the nearby lymph nodes, or certain subtypes of kidney cancer, such as clear cell RCC, may be more likely to experience lung metastases.

Other risk factors include:

• Delayed or no kidney removal surgery
• Cancer that grows into nearby blood vessels
• High-grade tumor (cancer cells that appear more abnormal or aggressive under a microscope)
• Incomplete resection of the metastases, if they were taken out

Your oncologist (cancer specialist) can help you understand details about your risk factors for lung metastases.

Symptoms of Lung Metastases

Lung metastases from RCC don’t always cause symptoms at first. Some people may feel completely fine. But as tumors grow in the lungs, they may begin to affect your breathing and overall health.

One of the earliest signs can be shortness of breath. You might notice it when walking, climbing stairs, or even at rest. A persistent cough that doesn’t go away is another common symptom. These signs may develop slowly, so it’s important to pay close attention to any changes in how you feel.

Other possible symptoms include:

• Coughing up blood
• Frequent lung or chest infections
• Chest pain or discomfort
• Unexplained weight loss

These symptoms can be caused by other health issues, too. But if you’ve had kidney cancer, it’s important to tell your healthcare team about any new or worsening symptoms. Early detection and diagnosis can make a big difference in improving your long-term prognosis (outlook).

How Are Lung Metastases Diagnosed?

Doctors use imaging tests and sometimes take biopsies (tissue samples) to find out if you have metastatic RCC that has spread through the body. These tests help show where tumors are, how big they are, and how many there might be.

Lung metastases are often found during routine follow-up after kidney cancer treatment. But if you have new symptoms like a cough or shortness of breath, your doctor may order tests sooner.

Common tests to check for lung metastases include:

• Chest X-ray — Usually the first imaging test to help find the cause of breathing difficulty or a persistent cough
• CT scan — Gives clear, detailed images of the lungs
• Positron emission tomography (PET) scan — Scans the whole body to reveal areas where cancer is active
• Biopsy — Removes and tests a small piece of tissue to confirm if cancer is present

Not everyone will need all of these tests. Your healthcare team will recommend the tests based on your specific situation and symptoms. If you have lung metastases, the sooner they’re found, the sooner treatment can begin.

Treatment Options for Lung Metastases

Metastatic RCC can’t usually be cured, but several treatment options can help slow its growth and improve quality of life.

Your individual treatment plan depends on several factors. These include:

• How many tumors are in the lungs
• Whether the cancer has spread to other areas
• Your overall health
• How well you tolerated earlier cancer treatments

Your doctor will also take into consideration your personal preferences and treatment goals, so be sure to speak up.

Treatment options may include:

• Immunotherapy — Helps the immune system recognize and attack cancer cells
• Targeted therapy — Blocks specific signals cancer cells need to grow and survive
• Metastasectomy (surgery to remove metastases) — May be considered in select cases
• Minimally invasive treatments, such as radiofrequency ablation, which uses heat to destroy tumors
• Radiation therapy — Rarely used, but may be considered in specific cases (e.g., for pain relief or if surgery isn’t an option)

Chemotherapy isn’t usually used to treat kidney cancer because it hasn’t been very effective against RCC.

Treatment for metastatic disease may require a combination of approaches. Each option comes with different potential side effects, so be sure to talk to your oncology team about the potential benefits and risks of each. They can also provide more information about what to expect during treatment and how to manage side effects if they do occur.

You may also be able to try new treatments currently being studied in clinical trials. If you’re interested in learning more about clinical studies, talk to your healthcare team. They can help you find out if there are studies recruiting in your area that you may qualify for.

How Do Lung Metastases Affect Prognosis?

Doctors often use five-year survival rates to describe the prognosis for a type and stage of cancer. This is a general estimate based on data from many people with the same type and stage of cancer. It predicts how many people will still be alive five years after diagnosis, but it can’t predict how long any one person will live.

According to the American Cancer Society, the five-year survival rate for people with stage 4 RCC, which includes those with lung metastases, is around 18 percent. However, this number may be higher or lower depending on your specific situation.

Some people with only a few lung metastases — especially if surgery can remove them completely — may live longer and have better outcomes. People who respond well to immunotherapy or targeted therapy may also have better outcomes.

If you’re concerned you may have lung metastases, talk to your doctor. You don’t have to face metastatic kidney cancer alone. Stay connected with your healthcare team, consider joining a support group with other people who understand, and prioritize taking care of your body and mind.

Talk With Others Who Understand

On MyKidneyCancerTeam, the social network for people living with rare kidney disease and their loved ones, members come together to ask questions, give advice, and share their stories with others who understand life with kidney disease.

Have you been diagnosed with lung metastases? What does your treatment plan look like now? Share your story in the comments below, or start a conversation by posting on your Activities page.