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Active Surveillance for Kidney Cancer

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Not all kidney tumors need to be treated right away. Some small kidney tumors turn out to be benign (not cancer). And even many small kidney cancers tend to grow slowly, without spreading.  

One option for some people with small kidney tumors may be to watch the tumor carefully to see if it grows, without treating it right away. This is usually done with regular imaging tests (ultrasound, CT or MRI scans) of the abdomen (belly). Blood tests and imaging tests of the chest might be done at times as well. If the tumor starts growing quickly or shows other worrisome signs, it can then be removed with surgery or treated another way.

Sometimes, the tumor might be biopsied to help determine if it is cancer or not. This could help determine if surveillance is a reasonable option, or if the tumor needs to be treated.

Active surveillance might be a good choice for people who are older or who have other serious health problems, as it can allow them to avoid the risks of treatments such as surgery or ablation.

If a biopsy hasn’t been done, watching the tumor closely for a while can also give the doctor a better idea of whether it is likely to be cancer, based on how fast it is growing. 

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 editors and translators with extensive experience in medical writing.

Campbell S, Uzzo RG, Allaf ME, et al. Renal Mass and Localized Renal Cancer: AUA Guideline. J Urol. 2017; 198:520-529.

McNamara MA, Zhang T, Harrison MR, George DJ. Ch 79 - Cancer of the kidney. In: Niederhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, Pa: Elsevier: 2020.

National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Kidney Cancer. V1.2024. Accessed at on December 13, 2023.

Pierorazio PM, Campbell SC. Diagnostic approach, differential diagnosis, and management of a small renal mass. UpToDate. 2023. Accessed at on December 13, 2023. 

Last Revised: May 1, 2024

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