Men who are uninsured or underinsured get advanced prostate cancer at nearly four times the national average and don't survive as long as other men with the advanced disease, according to the preliminary findings of a new study.

Prostate cancer, which usually occurs in older men, forms in tissues of the prostate (a gland in the male reproductive system found below the bladder and in front of the rectum).

"We've identified a group of advanced prostate cancer patients who do not do well," said Dr. Jeffrey Reese, chief of urology at the Santa Clara Valley Medical Center. Affiliated with Stanford University School of Medicine, Reese also has been seeing patients at the county hospital, which serves a large underinsured population in San Jose, Calif.

Of all men diagnosed with prostate cancer at the medical center from 1998 through 2008, Reese found 71 men, or more than 14 percent, had advanced prostate cancer. That's more than three times the national average of 4 percent who exhibit the symptoms of advanced cancer at the time of diagnosis.

"They come in invariably because they [are] having symptoms of metastatic disease," he said; the cancer, then, has already spread to other parts of their bodies. Yet, even though the men are offered all available treatments, their five-year survival rate is well below the national average, Reese found.

In 2013, the National Cancer Institute estimates there will be 238,590 new cases of and 29,720 deaths from prostate cancer in the U.S..

Testing for prostate-specific antigen or PSA measures the blood level, thought to be a key marker for prostate cancer. None of the 71 men - whose average age was 67 - had been tested for PSA before at the Santa Clara hospital, and Reese said he suspects that most or all had never had a PSA test anywhere.

Under new guidelines established on Friday, the American Urological Association (AUA) no longer recommends routine PSA testing for men, though it encourages discussion between men and their doctors, especially to those aged 55 to 69. The best evidence of the benefit from screening is among those men aged 55 to 69 screened every two to four years, according to the Association. Friday's announcement was a stark shift from the organization's previous attitude towards PSA testing and a decision not all doctors support. An annual PSA test is still covered for those on Medicare.

"The public hospital today gives you a snapshot of what it was like before PSA screenings," said Reese, who also found that survival of the men in the study was lower than the national average for men with advanced prostate cancer.

Less than 10 percent lived three years past the diagnosis. In comparison, 29 percent of men with advanced disease, overall, live at least five years after diagnosis, Reese said.

"Undoubtedly, a good portion of these men could have had their lives saved by PSA screening," commented Dr. Scott Eggener, an associate professor of surgery at the University of Chicago.

Reese will present his findings at the annual meeting of the AUA in San Diego.