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Active Surveillance for Kidney Cancer

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Some small kidney tumors are benign. And most (3 out of 4) small kidney cancers are slow growing.  One option for some people with these small kidney tumors (less than 4 cm[about 1½ inches]), may be to give no treatment at first and watch the tumor carefully to see if it grows. This is usually done by imaging tests (ultrasound, CT or MRI scan) every 3 to 6 months. If it grows quickly or gets larger than 4 cm, the tumor is removed or treated another way.

This approach is most often used for elderly or frail patients as it avoids the risks of treatment, such as surgery or ablation. Watching the tumor closely for a time helps doctors decide which tumors are more likely to be cancer based on their growth. Sometimes, a biopsy is done before deciding to watch the tumor to see if the lump is really cancer.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

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Last Revised: February 1, 2020

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