A National Prostate Cancer Coalition report showing an alarming increase in Hawaii's prostate cancer rate is not correct, cancer specialists here say. Experts dispute
prostate cancer rate
in HawaiiBy Helen Altonn
haltonn@starbulletin.comThe coalition reported that "prostate cancer is much more prevalent in Hawaii than experts thought."
It said the incidence rate, based on a National Cancer Institute study, has climbed to 135.5 per 100,000 men in Hawaii from 99.2 per 100,000 men.
"Those numbers just don't sound right from anything we have here," said Dr. Laurence Kolonel, Cancer Research Center of Hawaii researcher. "I think it's some kind of mistake."
The coalition said high prostate cancer rates in other states are explained by a large population of African Americans, at high risk for the disease, which Hawaii does not have.
Coalition spokesman Jamie Bearse said the organization cannot explain the sharp increase in its figures for Hawaii, but it could be that more men are getting screened for the disease and it is being found at an earlier stage.
Researchers at the Cancer Research Center of Hawaii suggest, however, that the coalition's figures may be based on an outdated government standard for comparing rates of disease, death, injuries and other health outcomes.
"I suspect they looked at old data adjusted to a different age standard," Kolonel said. "It's just a false impression that there has been an increase."
The United States used the 1970 population distribution as the age standard until 2000, when it was adjusted and the U.S. population in general had aged, he said.
The age-adjustment statistical process allows comparison of communities with different age populations.
"A younger population is going to look as though there is not much cancer," Kolonel said. "They can adjust for that and treat all populations as if they are adjusted by age.
"I wonder if they (the coalition) just didn't realize that. I wonder if they are comparing rates standardized to different populations."
Once the government changes the standard (every 30 years), he said, "We go back and redo everything so we can make comparisons to the new rates."
He said state rates for prostate cancer jumped enormously in the United States between 1989 and 1992 because of the Prostate-Specific Antigen (PSA) blood test, which measures the PSA enzyme.
Prostate cancer cases increased because of the test, but the mortality rate did not go up, he said. "The rates in all of our ethnic groups went down in the last few years -- not so much for native Hawaiians, but they have low rates to begin with."
Dr. Lyn Wilkins, statistician with the Hawaii Tumor Registry maintained by the Cancer Research Center and state Health Department, said rates will look higher with the standard adjusted to 2000 because it is weighted to an older population.
"So it may not be that the risk is higher, just that the people are older."
She said prostate cancer rates for Hawaii per 100,000 men, according to the Tumor Registry, were 127 from 1995 to 2000, 156 from 1990 to 1994 and 97 from 1985 to 1989.
"In the early 1990s, screening really pushed the rates up," Wilkins said. "Certainly, there was a huge increase in the incidence of prostate cancer in Hawaii, but I don't think it's still increasing. I think it peaked."
She said the risk of advanced cancers has declined in general since the mid-1980s because they are detected in earlier stages.
Hawaii death rates for prostate cancer have not varied that much, she said. They were 23 per 100,000 men from 1985 to 1989, 25 from 1990 to 1994 and 20 from 1995 to 2000.
National Prostate Cancer Coalition
National Cancer Institute
Cancer Research Center of Hawaii