Clear Cell Renal Cell Carcinoma
Clear cell renal cell carcinoma is the most common type of kidney cancer, affecting the cells that filter waste from your blood. While often discovered by chance during unrelated medical scans, this condition requires prompt attention and expert care to achieve the best possible outcomes.
Table of contents
- What is Clear Cell Renal Cell Carcinoma?
- Medical Identification Codes
- Affected Body Systems
- Who Gets This Cancer?
- Symptoms and Warning Signs
- Causes and Risk Factors
- Hereditary Factors
- How It Is Diagnosed
- Treatment Options
- Outlook and Survival
- Living With Clear Cell Renal Cell Carcinoma
What is Clear Cell Renal Cell Carcinoma?
Clear cell renal cell carcinoma, also called ccRCC or conventional renal cell carcinoma, is a type of kidney cancer that starts in the cells lining the small tubes in your kidneys[1]. These tubes are responsible for filtering waste products from your blood[2].
The cancer gets its name from how the tumor cells appear under a microscope. The cells look clear, like bubbles, because they contain lipids and other substances[2][5]. When cancer cells multiply rapidly, they form one or more tumors[1].
Clear cell renal cell carcinoma is the most common form of kidney cancer. It accounts for 70 to 80 percent of all renal cell carcinomas (a general term for kidney cancers), and makes up about 80 percent of all malignant kidney tumors[2][5]. While renal cell carcinoma comprises 90 percent of all kidney tumors, ccRCC represents the largest portion of these cases[3].
The cancer usually affects only one kidney, but it can affect both[1]. Clear cell tumors tend to spread through the bloodstream and can extend directly into major blood vessels, particularly the renal veins and the inferior vena cava (a large vein that carries blood to the heart)[3].
Medical Identification Codes
Healthcare providers use specific medical codes to identify and track clear cell renal cell carcinoma in medical records and research.
C64
Affected Body Systems
Clear cell renal cell carcinoma primarily affects the kidneys, which are a pair of bean-shaped organs located on either side of your spine toward your lower back[2]. Each kidney is about the size of your fist[6].
- Kidneys
- Renal tubules (small filtering tubes in the kidneys)
- Renal veins
- Inferior vena cava (when cancer spreads)
When the cancer spreads beyond the kidney, it most commonly reaches the lungs, bones, brain, liver, lymph nodes, and adrenal glands[3]. Bone involvement typically causes lytic bony metastases (areas where bone has been destroyed), which may become harder with treatment[3].
Who Gets This Cancer?
Anyone can develop clear cell renal cell carcinoma, but certain groups face higher risk. The cancer affects men twice as often as women[1]. It most commonly appears in people between 50 and 70 years old, with the average age at diagnosis being 64[1][6].
In adults, ccRCC is the most common type of kidney cancer[2]. However, it is more common in adults than in children. Renal cell carcinoma makes up only 2 to 6 percent of kidney cancer cases in children and young adults[2].
According to the American Cancer Society, more than 81,000 people in the United States receive a kidney cancer diagnosis each year, with ccRCC being the most common type[1]. The incidence of renal cell carcinoma has been rising[5].
Symptoms and Warning Signs
Clear cell renal cell carcinoma usually does not cause noticeable symptoms during the early stages[1][2]. In fact, healthcare providers discover about half of kidney tumors during imaging tests ordered for other reasons[7]. Kidney cancer does not usually cause symptoms until it has grown or spread[6].
As the condition progresses, you may experience:
- Blood in your urine, called hematuria[1][2]
- Feeling very tired even if you get a lot of sleep, known as fatigue[1][2]
- Fever[1][2]
- A lump on your affected kidney or in your side[1][2]
- Pain in your side, called flank pain[1][2]
- Unexplained weight loss[1][2]
It is important to remember that other types of cancer and noncancerous conditions can also cause these symptoms[4]. If you experience one or more of these symptoms, talk with a doctor to determine the exact underlying cause.
Causes and Risk Factors
Most kidney cancers, including ccRCC, develop for no known reason[1][4]. However, experts have identified several factors that may increase your risk.
The leading potentially modifiable risk factors include[3]:
- Obesity or having a body mass index (BMI) greater than 25. An increase in BMI of 5 kg per square meter, central body fat accumulation, and weight gain between ages 18 and 35 have been linked to developing renal cell carcinoma[1][3][13]
- Using tobacco products, including smoking cigarettes and vaping[1][4][13]
- High blood pressure, also called hypertension[1][4][13]
Other risk factors include:
- Chronic kidney disease that requires dialysis (a treatment that filters waste from your blood when kidneys cannot)[1][3]
- Renal transplantation[3]
- Acquired cystic kidney disease[3]
- A history of previous renal cell carcinoma[3]
- Co-existing diabetes mellitus[3]
- Exposure to workplace toxins, particularly the solvent trichloroethylene[1]
- Long-term use of pain relievers called analgesics, such as acetaminophen[1]
Hereditary Factors
You are at greater risk of kidney cancer if you have a blood-related sibling with renal cell carcinoma, though medical professionals are not sure why[1].
Clear cell renal cell carcinoma can run in families[2]. Almost all cases of ccRCC that run in families are found in people with a genetic condition called Von Hippel-Lindau syndrome, though other hereditary conditions may also be associated with ccRCC[2].
People with Von Hippel-Lindau syndrome have mutations in the VHL gene[2]. This inherited gene variation causes cysts and tumors to form in different areas of the body. The cysts and tumors are usually not cancerous. However, ccRCC can occur more often in these biological families, and it often develops at an earlier age than average[1].
The VHL gene is also changed in ccRCC from people without a family history of Von Hippel-Lindau syndrome[2]. Scientists have learned a great deal about what the VHL gene does in the body, which has given them clues about treatments to try for ccRCC[2].
If you receive a ccRCC diagnosis at a young age or have multiple tumors, your healthcare provider may recommend genetic testing[1].
How It Is Diagnosed
Because kidney cancer does not usually cause symptoms, healthcare providers discover most kidney tumors while looking for the cause of other conditions[1]. For example, they may see a kidney tumor on imaging tests like an MRI (magnetic resonance imaging) or CT scan (computed tomography scan) ordered to check for conditions like kidney stones[1].
Your doctor will use several approaches to diagnose clear cell renal cell carcinoma:
Physical exam and medical history: Your healthcare team will check your overall health, including vital signs like blood pressure, temperature, weight, and pulse. They will ask about medicines you take, any other health conditions, and whether any family members have had kidney cancer or other diseases[7].
Blood tests: Your team will take samples of your blood to check how well your kidneys are working and your overall health. Some blood tests include a Complete Blood Count (CBC) test, which measures the number of cells in your blood, and blood chemistry tests, which look at how well your liver and kidneys are working[7].
Urinalysis: A test of your urine looks for blood, extra proteins, or infection[7].
Imaging tests: Several types of scans can help detect and evaluate kidney tumors. A CT scan of your abdomen and pelvis shows your kidneys and nearby areas to see if the cancer has spread[7]. An MRI is used to check if kidney cancer has spread to major blood vessels or the brain[7]. A chest X-ray can show if the cancer has spread to your lungs[7]. A bone scan can show if the cancer has spread to your bones[7].
Imaging tests can detect a tumor, but it can be difficult to determine whether the mass is noncancerous (benign) or cancerous (malignant) based on imaging alone[1].
Biopsy: To make an accurate diagnosis, a provider may recommend a kidney biopsy or surgery to remove the tumor[1]. During a biopsy, a doctor removes a small sample from the tumor with a needle. An expert called a pathologist will study cells from the sample under the microscope to see what kind of tumor it is[2].
If a provider surgically removes the tumor, they will examine the tumor tissue for cancer. The results can confirm a cancer diagnosis and determine whether it is the clear cell subtype[1]. As many as 4 in 10 small kidney tumors (less than 4 centimeters) are noncancerous tumors[1].
After diagnosing ccRCC, a provider will determine the stage of the cancer to understand how far it has spread. This information helps guide treatment decisions.
Treatment Options
Treatment for clear cell renal cell carcinoma depends on how much the cancer has grown and whether it has spread[2]. Surgical resection is the mainstay of treatment for this disease[3].
Surgery: Treatment commonly involves surgery to remove the tumor or your entire kidney[1]. Once ccRCC is diagnosed, you may have surgery to remove the cancer and part of the kidney surrounding it[2]. In early stage ccRCC, part of the kidney with the cancer is taken out. If ccRCC is in the middle of the kidney, or if the tumor is large, sometimes the entire kidney must be removed[2]. In later stage ccRCC, removal of the kidney is controversial but may be appropriate in some patients[2].
Immunotherapy: Immunotherapy helps the body’s immune system fight the cancer cells[2]. This type of treatment has become an important option for treating ccRCC.
Targeted therapy: Targeted therapy targets the changes in cancer cells that help them grow, divide, and spread[2]. Some targeted therapies used to treat clear cell renal carcinoma include cabozantinib, axitinib, sunitinib, sorafenib, and pazopanib[2].
Other treatments that do not involve removing the kidney include[2]:
- Radiation therapy, which uses radiation to kill the tumor cells
- Thermal ablation, which uses heat to kill the tumor cells
- Cryosurgery, which uses liquid nitrogen to freeze and kill the tumor cells
Even in patients with disseminated tumor, locoregional forms of therapy may play an important role in relieving symptoms of the primary tumor[3]. The goals of managing advanced renal cell carcinoma emphasize improving quality of life[3].
Outlook and Survival
The estimate of how a disease will affect you long-term is called prognosis. Every person is different, and prognosis depends on many factors[2].
Renal cell cancer can often be cured if it is diagnosed and treated when still localized to the kidney and the immediately surrounding tissue[12]. The probability of cure is directly related to the stage or degree of tumor spread[12].
Even when regional lymph nodes or blood vessels are involved with the tumor, a significant number of patients can achieve prolonged survival and probable cure[12]. Because most patients are diagnosed when the tumor is still relatively localized and can be surgically removed, approximately 75 percent of all patients with renal cell cancer survive for 5 years[12].
The cancer-specific 10-year survival ranges from 71 percent in clear cell cancer to 91 percent in papillary cancer and 88 percent in chromophobe cancer[3]. As expected, diagnosis at an earlier stage offers a relatively higher chance of cure[3].
When distant metastases (cancer that has spread to other parts of the body) are present, disease-free survival is poor. However, some patients survive after surgical removal of all known tumor[12]. Occasionally, patients with locally advanced or metastatic disease may exhibit slow-growing courses lasting several years. Late tumor recurrence many years after initial treatment also occasionally occurs[12].
The percentage of distant metastases in clear cell carcinoma is about 15 percent[3]. Renal cell cancer is one of the few tumors in which well-documented cases of spontaneous tumor regression in the absence of therapy exist, but this regression occurs rarely and may not lead to long-term survival[12].
Living With Clear Cell Renal Cell Carcinoma
Living with clear cell renal cell carcinoma can affect your quality of life through symptoms like fatigue, pain, and weight loss, as well as treatment side effects. However, there are many steps you can take to feel your best.
Practice self-care: Self-care is an essential part of managing discomfort. It is about prioritizing your needs, care, and comfort so you can feel as well as possible. Give yourself time and space to rest, recover, and refresh your mind and body. This might include meditation, getting enough sleep, spending quality time with loved ones, or setting aside time for activities you enjoy. If you need help with appropriate exercise, your doctor can give you a referral for a physical therapist.
Eat a healthy diet: Eating a well-balanced diet with lots of fruits and vegetables can support your overall health, help preserve your strength, and reduce your risk of infection. Eating healthy foods and getting enough calories to stay at a good weight is especially important during treatment that can weaken your immune system. Your doctor can advise you on specific foods you may need to avoid due to your kidney function. Always discuss dietary supplements, including vitamins and minerals, with your doctor before trying them, as some supplements may interfere with cancer treatment. Your cancer care team can refer you to a registered dietitian who can help you plan a healthy diet suitable for you.
Work with your healthcare team to manage treatment side effects: Before considering a new treatment, discuss potential side effects with your doctor. Let your doctor know if you are having unpleasant side effects. Keeping a journal can help you track side effects. Always attend follow-up appointments to ensure your doctor knows if you are having side effects or any new or worsening symptoms. Do not make changes to your treatment plan without medical advice.
Maintain physical activity: It can be tough to exercise if treatment makes you feel drained, but moving your body is key to getting your energy back. Talk to your doctor or a physical therapist to come up with an appropriate routine.
Get support: Coping with cancer can be extremely difficult. Talking to others can help. As well as family and friends, there are plenty of people at the hospital and in your community who can support you. Specialist nurses can help if you are finding it difficult to cope or have any problems. Make sure you know who your specialist nurse is and have their number. Some people find it helpful to talk to a counselor. You may also find support through cancer patient communities and support groups.
Attend follow-up care: After treatment, regular follow-up appointments are essential. Your doctors will want to monitor you for signs of cancer recurrence and manage any long-term effects of treatment. Make sure you understand your follow-up schedule and attend all appointments.
