MONDAY, Nov. 12, 2012 (HealthDay News) -- Black patients with kidney cancer have lower survival rates than white patients do, a new study finds.
Researchers analyzed U.S. National Cancer Institute data on nearly 40,000 patients with renal cell carcinoma (the most common form of kidney cancer), and found that 72.6 percent of white patients survived at least five years, compared with 68 percent of black patients.
The higher survival rates among white patients appeared in all subgroups of patients, regardless of gender, age, tumor stage or size, tumor subtype or type of surgical treatment, according to Wong-Ho Chow, of the University of Texas MD Anderson Cancer Center in Houston, and colleagues.
A higher percentage of black patients were diagnosed with localized cancer and smaller tumors, or with a less aggressive subtype of kidney cancer. These factors should indicate a better prognosis, although the study found the opposite.
The researchers also found that a slightly higher percentage of black patients received no surgical treatment, which is associated with a substantially poorer prognosis.
The study was published online Nov. 12 in the journal Cancer.
Further research is needed to determine why black patients have lower survival rates than white patients.
"We cannot rule out the possibility that other factors not measured in our study -- such as obesity, high blood pressure, access to care and genetic susceptibility -- may be contributing to the persistent disparities," Chow said in a journal news release.
Since the mid-1990s, blacks have had a higher incidence of renal cell carcinoma than whites.
The U.S. National Cancer Institute has more about kidney cancer.