Stage IV renal cell carcinoma represents the most advanced phase of kidney cancer, where malignant cells have spread beyond the kidney to distant organs or lymph nodes throughout the body. While this diagnosis brings significant challenges, understanding the disease and available treatment options can help patients and families navigate this difficult journey with greater confidence and hope.
Understanding Stage IV Renal Cell Carcinoma
Stage IV renal cell carcinoma, also known as metastatic kidney cancer, occurs when cancer cells that originated in the kidney have traveled to other parts of the body. This happens when cancer has grown outside the protective layer surrounding the kidney called the fascia, or when it has spread to distant organs such as the lungs, bones, liver, brain, or lymph nodes far from the kidney. At this stage, the cancer may also have reached the adrenal glands, which sit on top of each kidney.[1][4]
The kidneys are two fist-sized organs located on either side of the spine, just beneath the ribcage. Their main job is filtering waste products and excess fluid from the blood, which then becomes urine. Inside each kidney are tiny tubes called tubules, and it is in the lining of these tubules where renal cell carcinoma begins to form. Renal cell carcinoma is the most common type of kidney cancer in adults, making up approximately 85 percent of all kidney cancer cases.[2][3]
When doctors talk about stage IV disease, they’re describing how far the cancer has traveled from where it started. Stage IV means the cancer is no longer confined to the kidney and surrounding structures. It has become systemic, meaning it affects multiple areas of the body. This makes treatment more complex, as the cancer must be addressed throughout the entire system rather than in just one location.[6]
How Common Is Stage IV Renal Cell Carcinoma
Healthcare providers diagnose approximately 80,000 new cases of renal cell carcinoma each year in the United States, and about 400,000 cases worldwide. The disease is more common in men than in women, and it most often affects people between the ages of 60 and 80. Not all of these cases are stage IV at the time of diagnosis, but some people discover they have advanced disease right from the start, while others develop metastatic cancer months or years after initial treatment for earlier-stage disease.[3]
According to estimates from the American Cancer Society, roughly 81,610 people will receive a kidney cancer diagnosis in a given year in the United States. Of these, around 52,360 are likely to be male and approximately 29,440 are likely to be female. Stage IV kidney cancer is considered the most difficult stage to treat because the tumors have grown throughout the body.[6]
Causes and Risk Factors
Renal cell carcinoma develops when certain changes occur in how kidney cells function, particularly in how they grow and divide. The exact cause of these cellular changes is not fully understood, but researchers have identified numerous factors that increase a person’s risk of developing the disease. It’s important to understand that risk factors don’t directly cause cancer in most cases. Instead, they increase the likelihood that DNA damage in cells will occur, which may eventually lead to cancer formation.[2]
Smoking tobacco is one of the most significant risk factors for renal cell carcinoma. The more a person smokes, the greater their risk becomes. This makes tobacco use a leading cause of not just kidney cancer, but many types of cancer and cancer-related deaths. The harmful chemicals in tobacco can damage cells throughout the body, including those in the kidneys.[2][11]
Long-term misuse of certain pain medications, including some over-the-counter pain relievers, has been linked to an increased risk of kidney cancer. People who take high doses of these medications over many years may be putting their kidneys at risk. Having excess body weight also increases the likelihood of developing renal cell carcinoma, and the risk grows as body mass index (BMI) increases. Similarly, people with high blood pressure, also known as hypertension, face a higher risk of kidney cancer.[2][3]
Family history plays a role as well. People who have close relatives with renal cell cancer may be at higher risk themselves, suggesting that genetic factors can contribute to the disease. Certain inherited genetic conditions, such as von Hippel-Lindau disease or hereditary papillary renal cancer, substantially increase the risk of developing kidney cancer. People with chronic kidney disease, which may include those who have been on long-term dialysis treatment, also face elevated risk. Additionally, chronic hepatitis C infection has been associated with a higher likelihood of developing renal cell carcinoma.[2][3]
Having one or more of these risk factors does not guarantee that someone will develop kidney cancer. Many people with multiple risk factors never get the disease, while some people with no known risk factors are diagnosed with it. However, being aware of these factors can help people make lifestyle changes that might reduce their risk and can encourage more vigilant monitoring of kidney health.[2]
Symptoms of Stage IV Disease
Many people with renal cell carcinoma, even at advanced stages, do not notice symptoms in the early phases. In fact, kidney cancer is often discovered accidentally during medical imaging performed for other reasons. However, when symptoms do appear in stage IV disease, they usually relate to how the tumor growth affects nearby tissues and organs, or to the presence of cancer in distant parts of the body.[3]
One of the most common symptoms is blood in the urine, a condition called hematuria. The urine may appear pink, red, or cola-colored, though sometimes the blood is only visible under a microscope. Pain in the flank, which is the area on the sides of the body between the hips and ribs, is another frequent symptom. Some people can feel a firm lump or mass in their abdomen, lower back, or flank area.[3]
Systemic symptoms, meaning those that affect the whole body, are also common with stage IV disease. These can include fever that comes and goes without an obvious cause, night sweats that soak through bedding, and unexplained weight loss. Many people with advanced kidney cancer experience extreme tiredness, known as fatigue, which doesn’t improve with rest. Some may develop symptoms of anemia, such as shortness of breath and feeling weak or exhausted, because the cancer affects the body’s ability to produce healthy red blood cells.[3]
When cancer has spread to specific organs, additional symptoms may appear. If the cancer has reached the bones, severe pain in the affected areas may occur. Bone metastases can cause pain that worsens over time and may lead to fractures. If cancer spreads to the lungs, people might experience persistent coughing, chest pain, or difficulty breathing. Brain metastases can cause headaches, confusion, seizures, or changes in vision or speech.[5][13]
Sometimes, tumors can release substances like hormones that cause changes throughout the body, resulting in what doctors call paraneoplastic syndromes. These unusual symptoms might include high blood calcium levels, high blood pressure, or abnormal liver function tests, even when the cancer hasn’t spread to those organs.[3]
Prevention
While there is no guaranteed way to prevent renal cell carcinoma, several lifestyle changes and health practices can help reduce the risk of developing the disease. Since some risk factors cannot be changed, such as age, genetics, or family history, focusing on modifiable risk factors becomes especially important.[2]
Quitting smoking or never starting is one of the most powerful steps a person can take to reduce kidney cancer risk. Tobacco use is a leading cause of cancer and cancer-related deaths, and stopping smoking can significantly lower the risk of renal cell carcinoma as well as many other serious diseases. Various resources and support programs are available to help people quit tobacco use.[2][11]
Maintaining a healthy body weight through balanced eating and regular physical activity can also reduce risk. People should aim to keep their body mass index within a healthy range. Working with a healthcare provider or registered dietitian can help develop an eating plan that supports healthy weight management.[3]
Managing blood pressure is another important preventive measure. People with high blood pressure should work with their doctors to control it through lifestyle changes and medication if necessary. Regular blood pressure checks can help detect problems early.[2]
Being cautious about the long-term use of pain medications, particularly over-the-counter pain relievers, may also help reduce risk. People who need to take these medications regularly should discuss this with their healthcare provider to ensure they’re using them safely and appropriately.[2]
For people with a family history of kidney cancer or known genetic conditions that increase risk, genetic counseling and regular screening might be recommended. These individuals may benefit from more frequent monitoring so that any problems can be detected and addressed as early as possible.[2]
What Happens in the Body: Understanding the Disease Process
Understanding what happens inside the body when someone has stage IV renal cell carcinoma can help patients and families grasp why certain symptoms occur and why specific treatments are chosen. The disease process involves both what happens in the kidney itself and how cancer cells spread to other parts of the body.[1]
Renal cell carcinoma begins when cells lining the tubules inside the kidney start to grow and divide in an abnormal, uncontrolled way. Normally, cells grow, divide, and die in an orderly fashion, with the body carefully controlling when new cells are made and when old cells die. In cancer, this control system breaks down. Cells continue to divide even when they shouldn’t, forming a mass of abnormal tissue called a tumor.[2]
As the tumor grows larger in the kidney, it may push against and invade nearby structures. It can grow through the outer covering of the kidney, extend into major blood vessels like the renal vein or the vena cava (the large vein that carries blood back to the heart), or spread to the adrenal gland that sits on top of the kidney. The tumor’s growth can disrupt normal kidney function, though often one healthy kidney can compensate for the diseased one, which is why some people don’t notice symptoms early on.[4]
In stage IV disease, cancer cells have broken away from the primary tumor and traveled through the bloodstream or lymphatic system to distant parts of the body. This process is called metastasis. The lymphatic system is a network of vessels and nodes that helps fight infection and filter waste. When cancer cells enter lymph nodes or blood vessels, they can travel to virtually any organ. The most common sites for kidney cancer metastasis are the lungs, bones, liver, and brain, though it can spread to other locations as well.[1][6]
When cancer cells reach a new organ, they may begin growing there, forming new tumors called secondary cancers or metastases. These secondary tumors can interfere with the normal function of whatever organ they’re in. For example, tumors in the lungs can make breathing difficult, while tumors in bones can weaken the bone structure and cause pain or fractures. Tumors in the liver can affect its ability to filter toxins from the blood and produce important proteins.[4]
The cancer can also affect the body in broader ways. Large tumors and widespread cancer can increase the body’s metabolic demands, leading to weight loss and fatigue. The immune system may become overactive or suppressed. Blood cell production in the bone marrow can be affected, leading to anemia and reduced ability to fight infections. Some tumors release substances that cause effects throughout the body, such as raising calcium levels in the blood or affecting blood pressure.[3]
Blood vessels that normally supply the kidney may also be affected. Cancer can stimulate the growth of new blood vessels to feed the growing tumor, a process called angiogenesis. These new vessels are often abnormal and leaky, which can contribute to bleeding. The involvement of major blood vessels by tumor growth can cause complications with blood flow and increase the risk of blood clots.[10]
