Signs and Symptoms of Kidney Cancer

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Medically reviewed by Gagandeep Brar, MD

Your kidneys remove waste products from your blood and flush out toxins from your body through your urine. These internal organs also control your body’s electrolytes and send signals to your bone marrow to make red blood cells. When cells in your kidney grow out of control, kidney cancer can occur.

Kidney cancer is rare and makes up about 2% of all cancers in the United States. Most people with kidney cancer don’t experience any symptoms in the early stages. Unfortunately, symptoms only start to occur when the cancer has progressed or when the tumors become larger.  If you develop symptoms, you may experience blood in your urine, lower back pain, and unexplained weight loss.

Common Symptoms

Many people with kidney cancer don’t show signs. in the early stages. In fact, kidney cancer is often found accidentally during a routine physical or imaging exam, such as an X-ray or MRI.

There are three main types of kidney cancers: renal cell carcinoma, transitional cell carcinoma, and Wilms tumors. As your cancer grows, you may experience the following symptoms that are common to all three types of kidney cancer:

• Blood in your urine
• Lower back pain that’s not caused by an injury
• A lump in your lower back or the side of your abdomen
• Loss of appetite
• Unexplained weight loss 
• Fever
• Anemia

Renal Cell Carcinoma Symptoms

Renal cell carcinoma, also known as renal adenocarcinoma or hypernephroma, is the most common type of kidney cancer. This type makes up about 85% of all kidney cancer cases. People assigned male at birth are more likely to have renal cell carcinoma than assigned females, but there does not seem to be a specific reason for this difference.

This type of kidney cancer forms in the main part of your kidneys. In the early stages, the cancer mass (tumor) is small and doesn’t always cause symptoms. About 25% of people with renal cell carcinoma do not experience any symptoms at all.

If you do develop symptoms, you may notice blood in your urine, a lump in your lower back or side, or lower back pain. However, having all these symptoms together only happens in about 10% of people with renal cell carcinoma.

Transitional Cell Carcinoma Symptoms

Transitional cell carcinoma makes up about 7% of all kidney cancers. This type of cancer does not start in the main part of your kidney. Instead, transitional cell carcinoma starts in your renal pelvis, the top part of your ureter. Your ureter is the tube that connects your kidney to your bladder. The cancer can stay in the renal pelvis or spread to the kidney or bladder as harmful cells continue to grow.

The cells that line your ureter are called transitional cells because they have characteristics of cells found in your kidneys and bladder and can change shape and stretch. Transitional cell carcinomas are also found in about 4% of people with bladder cancer.

You will not likely have symptoms when your transitional cell carcinoma is in the early stage. As your cancer grows, symptoms may include the common symptoms of kidney cancer alongside extreme fatigue and painful or frequent urination.

Wilms Tumor Symptoms

Wilms tumor, also called nephroblastoma, is a kidney cancer that happens in children, usually between the ages of 3-5 The tumors can develop in one or both kidneys. This condition is the most common pediatric kidney and abdominal cancer and is the fourth most common type of any pediatric (childhood) cancer.

Children with Wilms tumor usually do not experience symptoms until the cancer has metastasized (spread). This explains why a swollen or large abdomen is usually the first symptom a caregiver notices. Abdominal pain, which happens in 30-40% of children with Wilms tumors, is the most common symptom.

Some other symptoms of this type include high blood pressure and nausea. About 25% of children with Wilms tumor have high blood pressure. Fortunately, in many cases, removing the tumor reduces high blood pressure.

When to Contact a Healthcare Provider

Kidney cancers are usually found during a routine visit to your healthcare provider. However, if you notice any of the main symptoms such as blood in your urine, a lump or pain in the area of your kidneys, or sudden weight loss, see your healthcare provider as soon as possible.

If your healthcare provider suspects you may have kidney cancer, they may refer you to a urologist (a doctor who specializes in the urinary tract) or an oncologist (a doctor who specializes in diagnosis and treatment of cancer). These specialists can order tests to confirm a diagnosis and guide your treatment plan.

Questions To Ask Your Provider

If you have symptoms of kidney cancer and are seeing your healthcare provider, having questions ready for your appointment can help ease your concerns and learn more about this condition. Consider the following:

• Could blood in my urine be a sign of any other condition? 
• What does the kidney cancer testing process look like?
• If I receive a diagnosis of kidney cancer, what treatment options are available?
• What symptoms would mean that my cancer is getting worse?
• What is the life expectancy for someone with kidney cancer?

A Quick Review

Kidney cancer is a rare cancer that does not cause symptoms in the early stages. Unfortunately, most people don’t even know they have this condition unless a healthcare provider accidentally finds it after a routine doctor’s visit.

There are three main types of kidney cancer: renal cell carcinoma, transitional cell carcinoma, and Wilms tumor. They share many common symptoms, such as blood in your urine, pain or a lump in your lower back, unexplained weight loss, loss of appetite, and anemia. If you have these symptoms or may be at risk of kidney cancer, it’s important to see your provider right away to catch the condition early and get started on treatment.

Frequently Asked Questions

What is the life expectancy of a person with kidney cancer?

If your kidney cancer has not spread, your five-year survival rate is 92.9%. If it spreads to your lymph nodes, it drops to 73.8%. If it spreads to distant parts of your body, it is 17.4%.

What foods should you avoid if you have kidney cancer?

Avoid eating high-fat protein and red meat without lowering your protein intake.

Does kidney disease always cause kidney cancer?

Early stages of kidney disease do not cause kidney cancer. However, people with late-stage kidney disease have a 10- to 20-fold higher chance of developing kidney cancer.

Read the original article on Health.com.