SALT LAKE CITY — Last year, Lisa Calderwood of Midway received the diagnosis everyone fears: a terminal brain tumor.
"It took me a while to really process what was happening. I didn't understand at first," she said.
Calderwood is battling an anaplastic astrocytoma, one of the most common primary tumors of the adult brain.
"There are good days and bad days. Life still goes on whether I have a tumor or not," she said during a recent doctor's appointment at the Huntsman Cancer Institute.
In Utah, 150 to 160 people are diagnosed with brain cancer every year. That rate has increased steadily over the last 30 years.
"We really don't know why. The brain is protected by a blood-brain barrier, and so a lot of environmental causes that are involved with other cancers aren't able to get into the brain," said Sam LeFevre, an environmental epidemiologist with the Utah Department of Health.
LeFevre is conducting a statewide scan for gliomas — primary brain tumors that arise from cells of the brain itself rather than traveling to the brain from another location in the body.
"We are about a third of the way into a statewide scan to look for high areas or 'hot spots' for cancer in this study," he said.
Preliminary data indicates the following areas may have higher brain cancer rates:
- Southern portion of the Salt Lake Valley into the northern portion of Utah County
- Washington County
- Box Elder County
- Cache County
- Layton, in Davis County
In Layton, LeFevre said the risk for brain cancer may be five times higher than normal, but researchers are only 70 percent confident a cluster exists.
By the numbers:
- Between 1973 and 2010 there have been 3,892 cases of brain cancer reported to the Utah Cancer Registry
- 54 percent of the cases have been men
- 20 percent were children less than 20 years of age
- 7 percent were children 0-4 years of age
- For the last five years of data, 150-160 new cases have been diagnosed each year.
Source: Utah Department of Health
Because Utah's population is small, and brain cancer is rare, it is hard to get high enough statistical samples. Acceptable levels of statistical power require a 90- to 95-percent confidence level.
The state health department is using cancer data with the ZIP code geography provided by the Utah Cancer Registry. The UCR has one the best registries in the country, dating back to 1966. By law, all cancer cases are reported to the organization.
The health department will also use census data, which is referenced to geographies called census tracts.
"Once that is done, we will put the data into a statistical computer and look for clusters," LeFevre said.
"What I would say about the issue of cancer cluster (is) in many cases when these have been investigated, there hasn't been a significant increased risk over what you would expect in the general population," said Dr. Howard Colman, a member of the brain tumor and clinical research team at the Hunstman Cancer Institute.
The average risk of getting brain cancer in any one year is approximately 1 in 13,698, according to the Central Brain Tumor Registry of the United States.
"In general, there is a public sensitivity or wariness, scariness, about brain cancer," Colman said. "It is essentially a random chance in a particular cell at a particular time, and then that goes on to form a cancer."
While getting a brain tumor may, for the most part, rest on bad luck, technology continues to increase the odds of survival. And that gives patients like Calderwood a lot of hope.
"I've tried to stay positive," she said. "Prepare for the worst but hope for the best."