More detection of kidney cancer, but no decrease in mortality say researchers

Reported by Susan Aldridge, PhD, medical journalist

The rate of kidney cancer is up, because of earlier diagnosis, but the mortality rate from the disease has not gone down.
Smaller kidney tumors, which should be easier to operate on, are being diagnosed more readily. But new research from the University of Michigan has shown that this has not led to the expected decrease in mortality from the disease.

The researchers have been looking at data on 34,503 patients with kidney cancer diagnosed from 1983-2002. They say that over this time, there has been a rise in cases of renal cell carcinoma - the most common form of kidney cancer - and this includes tumors of all sizes. But the greatest rise in incidence was among those whose tumors were four centimeters or less in diameter. Advances in abdominal scans have led to the increased detection of small kidney tumors, which ought to be readily curable by surgery.

But mortality from kidney cancer has gone up from 1.2 deaths per 100,000 people in the USA to 3.2 deaths per 100,000. It seems that there has been a real increase in larger, more dangerous tumors, which are hard to treat. And the fact that the treatment of those with smaller tumors has not led to a decrease in mortality suggests that maybe people are being treated unnecessarily. Clearly it could be time to take another look at kidney cancer, its causes and how it is treated.

Source
Journal of the National Cancer Institute 20th September 2006