Fewer people die of prostate, bladder, and kidney cancers in counties with at least one urologist per 100,000 people, a new study shows. However, adding more than two urologists to a county without one doesn’t seem to add any benefit.

More than a third of counties in U.S. metropolitan areas lack a practicing urologist, according to study co-author Dr. Anobel Odisho, of the University of California in San Francisco, and colleagues. Outside of metro areas, as many of 60 percent of counties don’t have a practicing urologist.

Odisho and his team wanted to see if this uneven distribution has a measurable effect on cancer deaths. The California researchers turned to data from 2000 to 2005 from the US Census Bureau, the National Cancer Institute, and the Centers for Disease Control. They took into account doctor specialties, population and doctor distribution, income and education levels, and ethnicity.

Writing in the April 20 online edition of the Journal of Clinical Oncology, the researchers write that adding a urologist per 100,000 people to a county without one was linked to about a 16 percent lower risk of death from prostate cancer.

In bladder cancer, a disease that usually requires close follow-up after initial treatment, the presence of 1 or 2 urologists per 100,000 people was associated with an 18 percent drop in mortality. In kidney cancer, access to an urologist was associated with about a 12 percent drop in deaths due to the disease.

Overall, rates of deaths due to the three cancers were still low: About 30 men per 100,000 died each year of prostate cancer, and about 5 people per 100,000 people per year died of bladder or kidney cancer.

There was a big difference between counties with zero urologists per 100,000 and two, Odisho said, but surprisingly, the benefit - as seen through lower cancer deaths - of adding more urologists reached a plateau at 2 urologists per 100,000 people in a county.

The finding conflicts with the assumption that having more doctors is always better, Odisho said.

So while some counties may need a urologist or two, others may have far too many. “There are a lot of areas of the country where the nearest urologist is over 150 miles away and for someone with bladder cancer, who needs to see their urologist as often as every three months - that poses a severe burden,” Odisho told Reuters Health.

Still, the results don’t explain why there were fewer deaths, and don’t prove that having more urologists actually caused the drop. Heart disease is the leading cause of death in the U.S., and cancer ranks second, with prostate, kidney and bladder cancers below the top cancer killers: lung and breast cancer.

The study did not look at other causes of death, so there’s no way to know whether people were actually living longer, or just not dying of cancer but still dying at the same age of other diseases. Other studies have found that adding a primary care doctor, rather than a specialist, led to about one fewer death per 20 people over a given period of time.

Odisho said, however, that too few new urologists are being trained every year and those that are tend to gravitate toward large metro areas instead of toward the underserved U.S. counties.

SOURCE: http://jco.ascopubs.org/cgi/content/abstract/JCO.2009.26.9597v1 Journal of Clinical Oncology, online April 20, 2010.