Majority Diagnosed at Earliest Stage

Christopher J. Kane, M.D., chief of urology at UC San Diego Medical Center and the Moores UCSD Cancer Center, and a team of researchers, analyzed records of more than 200,000 kidney cancer patients described in the National Cancer Data Base to look at how kidney cancer presentation has changed over a twelve-year period.

The analysis looked at kidney cancer data between 1993 and 2004. Findings reveal that stage I kidney cancers increased from approximately 43 percent in 1993 to 57 percent in 2004, but decreased in stages II-IV of the disease. The average size of the stage I tumours decreased from 4.1 cm in 1993 to 3.6 cm in 2003. Overall survival for all patients with kidney cancer increased 3.3 percent between 1993 and 2003. The 5-year survival rate for people with stage I kidney cancer is now 88 percent or better.

While the reason for the downward trend is not known with certainty, the low stage presentation of tumours appears to be due to the more widespread use of medical imaging such as ultrasound, CT scans, and MRIs being conducted to evaluate other medical conditions. The cancerous growths, which often have not yet caused symptoms, are found unexpectedly as a result of these imaging tests.

These “incidentally detected” masses are more likely to be benign, smaller, and when confirmed to be kidney cancer to have better rates of survival. “What we are seeing is that gynecologic or abdominal imaging to evaluate pain or other complaints is picking up other forms of disease such as kidney cancer,” said Kane.

“The increased and widespread use of medical imaging in the United States is helping to diagnose cancer in its non-symptomatic stages when it is easier to treat successfully. The message to patients is not to go out and request an ultrasound or CT scan,” said Kane. “Keep in mind that this is a rare form of cancer. However, if abdominal imaging is done and a mass or masses in the kidney are recognized, evaluation by an urologist is recommended.”; Source: University of California - San Diego