Cancer sufferers are more likely to die from their condition if their kidneys are not functioning properly, a new study published online in the American Journal of Kidney Diseases claims.
Dr. Germaine Wong from the University of Sydney led the research, which shows that even mild to moderate reduction in kidney function increased the rate of cancer mortality.
According to the National Kidney Foundation, 26 million Americans have kidney disease, but as it does not have symptoms until it is advanced, it often goes undiagnosed.
Dr. Wong's previous research has shown that patients with chronic kidney disease (CKD) are more likely to develop cancers, but this study demonstrates that they are also more likely to die from it, compared with patients with normal kidney function.
Urinary tract and breast cancers worsen prognosis
The researchers conducted a prospective population-based cohort study of 3,654 individuals who had participated in the Blue Mountains Eye Study.
The study notes that those suffering from chronic kidney disease were at least 1.3 times more likely to die from cancer, compared with those without kidney disease.
This link was even more pronounced among sufferers with urinary tract cancers - a 2.5-fold increase - and women suffering breast cancers, who were more than twice as likely to die if they also had kidney disease.
Dr. Wong explains:
"People with chronic kidney disease are more likely to develop urinary tract cancers. But as for breast cancer, we suspect it could be a matter of under-treatment. For example, we already know that women with CKD are less likely to be screened for cancer as a whole. So, their cancers may be more advanced before they receive treatment."
Reduced kidney function greatly increases the risk of death from cancer, researchers say.
The National Kidney Foundation points out that diabetes - a condition affecting 26 million Americans - is the leading cause of kidney disease, closely followed by high blood pressure - currently affecting 73 million Americans.
Dr. Joseph Vassalotti, chief medical officer for the National Kidney Foundation, advocates screening at-risk individuals for kidney disease, stating:
"Early detection will ensure patients are aware of their condition and the increased risks that cancer and cardiovascular disease pose to those with chronic kidney disease."
Dr. Wong continues:
"Cancer in a patient with chronic kidney disease is a bad prognosis. Hopefully we can work toward screening in patients with kidney disease so that prevention measures and monitoring can be initiated early and lives can be saved."
She calls for more research to find out why people with chronic kidney disease are at an increased risk for cancer and why they have such a poor prognosis.
Dr. Wong and her team are currently conducting a study to predict the benefits and costs of screening for cancers in patients with chronic kidney disease.