Kidney cancer, also known as renal cell carcinoma (RCC), is one of the 10 most common cancers in people. Doctors most commonly diagnose this cancer in people over 60 years old, often after finding it by accident during routine imaging tests.

The kidneys are two bean-shaped, fist-sized organs under the back of your rib cage. They help:

  • filter waste from your blood
  • create urine
  • control blood pressure
  • create red blood cells

Your body can function normally with only one kidney. But a tumor growing in one of your kidneys can disrupt its normal functions.

Most symptoms of kidney cancer have to do with kidney function and tumor growth, but these symptoms often don’t appear in the early stages.

When symptoms do appear, they tend to show up in places like your urine or lower back.

Blood in the urine

Hematuria, or blood in the urine, is the most common symptom of kidney cancer.

Even a small amount of blood can cause a color change. Your urine might appear:

  • pink
  • brownish
  • red

The presence of blood can be inconsistent, appearing about every other day. Sometimes the amount of blood is so small that only a urinalysis can detect it.

Other possible reasons you might notice blood in your urine include:

It’s always best to make an appointment with a doctor or other healthcare professional (HCP) as soon as you notice blood in your urine.

Lower back pain

Many people over 40 years old experience back pain, usually due to musculoskeletal injury or disc degeneration.

Back pain can also be a symptom of kidney cancer, but most people don’t experience back pain until the cancer has reached the later stages.

This pain can vary from person to person. You might notice:

  • a dull ache below the back of your ribs or on one side of your flank (the area between your lower back and the bottom back of your ribs)
  • a sharper stabbing pain in the same location
  • pain on one side only
  • pressure rather than an ache or sharp pain

You’ll usually want to connect with a doctor or other HCP if you have any sudden, persistent pain that lasts more than a few days. Mentioning any other symptoms during your visit can help them determine the most likely cause.

A mass or lump around your abdomen

A mass or lump in the abdomen, side, or back can also be a sign of kidney cancer. You might feel a hard thickening or bulging bump under your skin.

But kidney lumps are hard to feel, especially in the early stages. That’s because the kidneys sit deep in the abdomen. You may not even see or feel the lump as the tumor grows.

If you do discover a lump, a doctor or other HCP will likely order diagnostic tests, such as an ultrasound or a CT scan. These tests may help determine the cause of the lump. You’ll typically need a biopsy to confirm the diagnosis.

Keep in mind that not all lumps are cancer. If you’re concerned about a lump around your abdomen, a doctor or other HCP can offer guidance and information about next steps.

Fatigue

Fatigue happens commonly with any type of cancer. According to a 2020 research review, nearly half of people with cancer experience fatigue. Fatigue is especially common during cancer treatment, too.

Fatigue from cancer is different than just feeling tired from lack of sleep. Cancer-related fatigue is persistent and interferes with daily activities. It can also intensify as time goes on.

Anemia

Anemia, or low red blood cell count, can also happen as a symptom of kidney cancer. Healthy kidneys signal your body to make red blood cells, but cancer can interfere with that signaling.

Anemia can also cause:

If you feel unusually tired, a good next step involves making an appointment with a doctor or other HCP. They can run tests to help diagnose the cause and find the right treatment.

Appetite loss

While appetite loss can have a range of causes, it can occur as a symptom of cancer. Appetite loss might happen when growing tumors affect typical digestive processes or the production of hormones in your body.

If you suddenly lose interest in eating and nothing seems appetizing, you may want to consider connecting with a doctor or other HCP to explore possible causes of appetite loss.

Unexpected weight loss

People with kidney cancer commonly report weight loss when not trying to lose weight.

Weight loss, which can happen in part due to appetite loss, may happen quickly as the tumor spreads to other organs.

Fever

A fever on its own doesn’t usually suggest kidney cancer. That said, unexplained and recurring fevers can happen as a symptom.

These fevers aren’t usually caused by an infection. You might notice your fever comes and goes, or simply won’t go away.

Swelling in your legs and ankles

Edema, or swelling in your feet, ankles, legs, and hands, can also occur as a symptom of kidney cancer.

This swelling happens when fluid builds up in your body’s tissues. Your kidneys typically help remove this fluid, but the growing cancer can prevent them from working as they should.

Many people with kidney cancer don’t notice any early signs or symptoms until the cancer’s later stages, or until the tumor is large. Research suggests, in fact, that over half of all people diagnosed with RCC have no symptoms at the time of diagnosis.

Some of the earliest symptoms you might notice include:

  • blood in your urine
  • anemia and related fatigue
  • loss of appetite
  • unexplained weight loss

It’s always a good idea to make an appointment with a doctor or other HCP if you feel generally unwell and:

  • your feelings of illness or fatigue last for more than 2 weeks
  • your symptoms get worse over time

Some people have a greater chance of developing kidney cancer than others. Risk factors include:

  • age (as you get older, your chance of kidney cancer increases)
  • smoking
  • obesity
  • high blood pressure
  • treatment for kidney failure
  • certain genetic or hereditary factors
  • male gender

Experts have also linked certain health conditions to increased kidney cancer risk. These include:

You can take certain steps to prevent or lower your risk for kidney cancer, including:

Letting your physician know if you have a personal or family history of cancer can help them better determine your specific risk factors for developing RCC.

If you’ve noticed any of the symptoms mentioned above, you’ll want to make an appointment with a doctor or other HCP as soon as possible. Connecting with a doctor promptly becomes even more important when certain factors raise your risk of developing kidney cancer.

If you have any symptoms of kidney cancer, a doctor or other HCP will typically:

  • Order tests to help determine the cause. Possible tests include a urinalysis, urine culture, and blood tests to check for anemia, along with an analysis of liver, kidney, and other metabolic functions.
  • Perform a physical exam. They may try to feel a lump or mass by examining your abdominal area. Kidney cancer often can’t be detected through a physical exam, though, so they’ll usually only feel larger masses.
  • Recommend imaging tests. If they find a lump, they’ll likely recommend imaging tests, such as ultrasound, CT scan, or MRI to get more information.
  • Recommend a biopsy. When imaging tests reveal a lump or mass, you’ll generally need a biopsy to determine whether or not it is cancerous.

Symptoms of kidney cancer can develop with other, less serious health conditions. But because they can suggest kidney cancer, especially when they occur together, ignoring them can have serious health consequences.

Getting a diagnosis sooner rather than later can improve chances of treatment success, not to mention your long-term outlook with the condition.

Kidney cancer often shows no signs until later stages. That’s what makes it so important to connect with a doctor or other HCP as soon as symptoms arise, particularly when you have a family history or other risk factors.

Prompt diagnosis could increase your options for treatment, help you explore strategies to manage kidney cancer, and lead to an improved outlook overall.