Kidney cancer is the 8th most common cancer in the US. Almost 75,000 people are diagnosed with this cancer every year. The incidence of kidney cancer seems to be increasing but that may be a false impression. Let’s talk more about this common cancer.
What is kidney cancer?
It seems obvious, but kidney cancer is a type of cancer that begins in the kidneys. Cancer that spreads to the kidneys after starting in another organ is not considered primary kidney cancer.
The most common type of kidney cancer in adults is renal cell carcinoma. Young children are more likely to have a different type of kidney cancer, called Wilms’ tumor. There are also some other types of kidney cancer that are much less common, including renal medullary carcinoma, clear-cell sarcoma, and transitional cell carcinoma.
Is kidney cancer becoming more common?
The incidence of kidney cancer seems to be increasing, but this may be because tests such as CT scans are being done more frequently now than they were in the past. Small kidney masses are often found incidentally when these imaging studies are done for symptoms unrelated to the kidneys. We now know that small kidney masses may be present for many years without causing any problems at all. Maybe we just didn’t see them before because we weren’t looking.
What are the symptoms of kidney cancer?
Kidney cancer may not cause any symptoms at all in the early stages. When kidney cancer is more advanced, symptoms can include:
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Blood in the urine
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Back or flank pain that is persistent
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Unexplained weight loss
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Loss of appetite
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Fatigue or feeling tired
What factors increase your risk for kidney cancer?
Although we do not know exactly what causes kidney cancer, we have identified some things that increase your risk for developing this cancer. They include:
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Smoking (risk decreases after you quit smoking)
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Older age – Risk increases as you get older.
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Obesity
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High blood pressure
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Being on dialysis for kidney failure
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Family history of kidney cancer
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Certain genetic or inherited conditions, such as tuberous sclerosis, von Hippel-Lindau disease and others.
Are all kidney masses cancerous tumors?
No. We have learned that most kidney masses discovered incidentally on imaging studies are benign (either cysts or benign tumors). If they are malignant, they are usually very low-grade cancers with limited potential to spread.
Masses in the kidney that are less than 4 centimeters (cm) in size are classified as small renal masses (SRMs), and their growth rate and the possibility of spreading to other areas of the body are extremely low. We will talk more about SRMs in an upcoming Health Tip.
Can you prevent kidney cancer?
You certainly can reduce your risk of developing this cancer by taking steps to improve your health, such as:
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Quit smoking
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Maintain a healthy weight
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Control high blood pressure
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Exercise regularly
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If you are diabetic, maintain good blood sugar control and talk with your doctor about medications that can protect your kidneys against damage from diabetes.
Next week, we will continue our discussion about kidney cancer and small renal masses.
If you have any questions about kidney cancer, please log into your account and send us your question. We are here to help.
Dr. Anita Bennett MD – Health Tip Content Editor