MONDAY, Feb. 13, 2006 (HealthDay News) -- Previous studies have shown that black men don't live as long after being diagnosed with prostate cancer as white men do.
However, new research suggests that factors such as poverty and a lack of education -- rather than race -- may be primarily to blame.
"If you have patients all at the same level on the socioeconomic scale, with equal housing, nutrition, access to care, and optimum therapy, race plays no role," noted lead researcher Dr. Xianglin L. Du, an associate professor of epidemiology at the University of Texas Health Science in Houston.
His team studied a database of more than 61,000 prostate cancer patients aged 65 and older, all of whom had some form of health coverage. They found that education, poverty and income levels were better indicators of survival than race. Age, disease stage and treatment methods also had an impact.
Researchers from the M.D. Anderson Cancer Center in Houston also contributed to the study, which appears in the Feb. 13 online issue of Cancer.
Men of lower socioeconomic status did not live as long after diagnosis as did wealthier patients, the team found. In fact, men who placed in the bottom 25 percent in terms of income had a 31 percent higher risk for death, compared to more well-off patients. That risk didn't change significantly when the team adjusted for race.
The researchers also found that "a large proportion" of black and Hispanic patients were poorly educated, with a much higher likelihood of having incomes at or below the poverty level, compared with white patients.
Just over 73 percent of blacks and close to 61 percent of Hispanics placed in the bottom quarter in terms of income, compared with about 18 percent of whites.
The sample of prostate cancer patients is the largest ever studied, said Du. The data was taken from the federal government's Surveillance, Epidemiology, and End Results (SEER) cancer database. All patients had been diagnosed with local (limited to the prostate) or regional stage (spread outside the prostate) carcinoma between 1992 and 1999.
Prostate cancer -- generally a slow-growing malignancy -- is one of the most common cancers in men. The American Cancer Society estimates there will be about 234,460 new cases diagnosed this year, with two out of every three cases occurring in men over the age of 65.
A previous study in the same journal found that all groups generally receive the same level of care, although black men are more likely to choose radiation therapy, while white men more often opt for invasive surgery to eradicate the cancer.
However, other studies have shown that black men are more likely to get prostate cancer and to be diagnosed at later stages, noted Dr. Thomas Fogel, a radiation oncologist in Ventura, Calif., and a volunteer with the American Cancer Society.
While it is not yet known why black men might be more prone to the disease, late diagnoses appear to be related to socioeconomic issues as well, he said.
"Men who don't have the ability to get into the system and be diagnosed and treated are going to be doing worse then men who have access to the system," Fogel said. In this study, he said, "you actually have statistics on a disease that validates that which we all intuitively know is an enormous issue."
"The implication, for me, is that if the largest variable for outcome is socioeconomic status, that is basically a surrogate for access to care," he said. "We need to do something."
More information
The National Cancer Institute can tell you more about prostate cancer.