FRIDAY, May 1 (HealthDay News) -- Older men who suffer from moderate chronic kidney disease appear to have a higher risk for developing certain kinds of cancers, a team of Australian scientists report.
The observation -- which suggests a bump in the risk for lung and/or urinary cancer, but not prostate cancer -- adds to previous evidence that patients with end-stage renal disease and those undergoing kidney transplantation are at an increased risk for developing a malignancy.
Results of the research effort, led by Dr. Germaine Wong from the Center for Transplant and Renal Research at Children's Hospital in Westmead, Australia, are being published in the April 30 online issue of the Journal of the American Society Nephrology.
According to the National Kidney Foundation, 26 million Americans currently suffer from chronic kidney disease, and seniors -- along with blacks, Hispanics, Native Americans, and Pacific Islanders -- face a particularly high risk for developing the illness.
In the new study, Wong and her colleagues analyzed a decade's worth of data on more than 3,600 Australian men who were between the ages of 49 and 97 and predominantly white.
Noting that nearly 20 percent of the men went on to develop cancer during the study period, the research team found that moderate kidney dysfunction was, in fact, associated with a 39 percent increased risk for certain cancers.
They further noted that men with "significant" kidney disease faced three times the risk for developing cancer, as compared with those men who retained normal kidney function.
While highlighting the need for more research, the Australian team theorize that kidney disease and cancer could be linked via the systemic inflammation that results from chronic kidney disease.
Dr. Matthew Weir, director of the division of nephrology at the University of Maryland School of Medicine in Baltimore, described the findings as "important new information."
"We've known for many years that people with end-stage kidney disease have an increased risk for malignancy in general, and renal cancer in particular," he noted. "And this study provides a logical extension of this previous observation, in that we now see that there is a graded relationship of risk for cancer, and that once again renal disease is the top of the list."
"So people with chronic kidney disease need cancer screening," Weir added, "and we need to pay attention to how we monitor them for this risk. And it is also important that patients who are referred for organ transplantation, which is one of the best options for people with chronic kidney disease, are carefully worked up regarding immunosuppression, so that we're not transplanting people with [hidden] malignancies."
Dr. Robert Provenzano, chief of nephrology at St. John Hospital and Medical Center in Detroit and vice-president of medical affairs for DaVita, the country's largest dialysis provider, agreed that the current finding makes sense given the information researchers already have regarding kidney disease.
"Over the last five years we've come to know that right out of the box all patients with chronic kidney disease of any severity have a much higher mortality rate then those who don't," he noted. "So, this finding about a link between moderate kidney disease and cancer doesn't surprise me, because the notion that one can have 'mild' kidney disease is a misnomer to begin with. It's like saying you have mild AIDS. If you have kidney disease of any severity at any age then your inflammatory response is triggered by definition, period. And this leads to all sorts of bad things, such as inflaming the lining of your blood vessels, which can lead to a heart attack, or negatively impacting your ability to kill cancer cells."
"And the probability of getting both chronic kidney disease or cancer simply goes up with age," Provenzano said. "It's just a fact. So the message here is that even for so-called mild chronic kidney disease, doctors and patients need to be vigilant about being monitored for these concerns."
For additional information and resources on chronic kidney disease, visit the National Kidney Foundation.
SOURCES: Robert Provenzano, M.D., chief, nephrology, St. John Hospital and Medical Center, Detroit, and vice president, medical affairs, DaVita, Los Angeles; Matthew Weir, M.D., professor, medicine, and director, division of nephrology, University of Maryland School of Medicine, Baltimore; April 30, 2009, Journal of the American Society Nephrology, online