WRITER: JENNIFER BROWN
Cancer is the second leading cause of death in Iowa behind heart disease. This year, an estimated two of every 1,000 Iowans, or 6,300 people, will die from cancer, according to "Cancer in Iowa: 2002," the annual report issued by the State Health Registry of Iowa, based at the University of Iowa College of Public Health. The report also estimates that an additional 14,600 individuals will be newly diagnosed with cancer during 2002.
Lung cancer remains the most common cause of cancer death in men and women,
accounting for almost one-third of cancer deaths in men and one-fifth of cancer
deaths in women. The report estimates that 1,700 Iowans will die from lung
cancer in 2002.
The report also finds that the three most common types of newly diagnosed cancer for men and women, excluding non-melanotic skin cancer, are the same as in prior years. For men, prostate cancer is the most common, followed by lung cancer and cancer of the colon and rectum. Breast cancer, which accounts for three of every 10 newly diagnosed female cancers, remains the most common cancer in women. Cancer of the colon and rectum and lung cancer follow breast cancer.
Together, breast, colon and rectum, lung and prostate cancers will account for more than half of all new cancers in Iowa.
Overall cancer rates are similar to previous years, said Charles F. Lynch, M.D., Ph.D., UI professor of epidemiology and medical director of the Iowa Cancer Registry.
Breast cancer is the second most common cause of cancer death in females in Iowa. This year's report includes a special section on breast cancer. Breast cancer can occur in men, but men are 150 times less likely than women to develop this cancer.
Data from the State Health Registry show that there has been an almost six-fold increase in rates of in situ breast cancer (confined to the originating site within the breast) detected since the early 1980s. The data also show that the rates of death from breast cancer have been steadily declining in Iowa since 1992.
"The picture for breast cancer in Iowa is improving," Lynch noted. "There has been a decrease in mortality rates and an increase in the proportion of women diagnosed with breast cancer when the disease is still confined to the breast. We are making progress with this disease at a public health level."
The report notes that detecting breast cancer when the cancer is still confined to the breast is one of the keys to reducing death from this disease. In the mid-1970s, five of every 10 newly diagnosed breast cancers in Iowa women were confined to the breast, whereas by the late 1990s this had increased to seven of every 10.
"The five-year relative survival rate for this stage of breast cancer is better than 90 percent," Lynch said.
Mammography is considered to be the most effective screening tool for identifying breast cancer in its early stage. Despite recent reports questioning the usefulness of mammography, the American Cancer Society continues to recommend that women over age 40 get an annual mammogram and clinical breast exam.
"Despite the progress made in increasing the number of women who get mammograms, 1999 data from Iowa's Behavior Risk Factor Surveillance System found that more than 10 percent of women 40 to 49, 50 to 59, and over 65 years old have never had a mammogram," Lynch said. "These are significant percentages and we would like to further decrease them. One way this is currently being approached is through the development of a comprehensive cancer control plan for the state of Iowa."
In addition to gender, age is a major risk factor for developing breast cancer. The Iowa data show that age-specific breast cancer rates are higher for women age 65 and older relative to younger women.
Other important risk factors for developing breast cancer include a woman's overall lifetime exposure to estrogen and her genetic predisposition to the disease.
Exposure to estrogen is influenced by many factors, including early age of first menstruation (period), late onset of menopause and long-term use of hormone replacement therapy.
A genetic predisposition to breast cancer is often evident from a woman's family history of breast cancer. Women who have first-degree female relatives (mother, sister or daughter) who have been diagnosed with breast cancer may be genetically predisposed to develop the disease. The American Cancer Society recommends that these women get annual mammograms before age 40.
More than 150 hospitals, clinics and medical laboratories across Iowa, in addition to referral facilities in neighboring states, contribute data to the State Health Registry. Lynch stressed the important role of these contributions in providing for a thorough tracking of the cancer experience of Iowans. The registry is one of 14 registries nationwide that are currently funded to provide data to the National Cancer Institute.
The State Health Registry has been gathering cancer incidence and follow-up data for the state since 1973 and includes projected numbers of new cancer diagnoses and cancer deaths for each county.
Links to the "Cancer in Iowa: 2002" report and reports from previous years are available at http://www.public-health.uiowa.edu/shri. People may also request a copy of the report by calling the State Health Registry of Iowa at (319) 335-8609.