Kidney and renal pelvis cancers are among the leading causes of cancer death in the United States. Kidney cancer is 9th on the list of the 10 most common types of cancer. Almost all of the kidney cancers in the United States are renal cell carcinomas (RCC). These cancers form in the lining of the small tubes in the kidney.
There are no routine lab tests to find kidney cancer. Often tumors are found during genetic screening, or when they are seen on imaging (like ultrasound or CT scan) when you see a doctor about another problem.
In many cases, the urologist can tell by appearance on a scan whether a mass in the kidney is a cancer or not, but sometimes that is not the case. If so, a renal mass biopsy may be done to find out if the mass is a cancer. A biopsy is when cells or tiny parts of an organ are removed and studied. For renal mass biopsy, your doctor uses imaging to guide a small needle through the skin into the mass. A pathologist views the sample under a microscope. A pathologist is a doctor who can check for signs of cancer.
The biopsy will show if the tumor started in another part of your body or if it started in the kidney. A biopsy may also tell if there is an infection, such as an abscess. It can help find cancer and help you make better treatment choices.
Dr. J. Stuart Wolf is associate chair of clinical integration and operations and professor for the Department of Surgery and Perioperative Care at Dell Medical School at the University of Texas in Austin.