State Health Department Releases Prostate Cancer Maps
Latest Production Includes Zip Code, Late Stage and Racial Patterns Maps
Albany, NY, November 20, 2001 – The New York State Department of Health today released a series of maps depicting new cases of prostate cancer, including prostate cancer incidence by ZIP Code across the State.
The prostate cancer maps, the latest component of Governor Pataki's Cancer Surveillance Improvement Initiative (CSII), follow previous county–level maps representing 11 different anatomic sites of cancer, and ZIP Code maps of breast cancer, lung cancer and colorectal cancer incidence.
"These maps focus attention on an issue that is critical to men's health," State Health Commissioner Antonia C. Novello, M.D., M.P.H., Dr.P.H. said. "More than 11,000 New Yorkers are diagnosed with prostate cancer in the State every year, and more than 2,300 die. Questions that remain to be looked at further include the effects of screening, and whether prostate cancer mortality is directly related to being medically–underserved or some other unknown factor. These maps will help to focus these questions and allow health officials to concentrate additional resources in specific problem areas."
Factors affecting prostate cancer incidence:
Risk factors for prostate cancer include age, race (Black men have a higher risk for prostate cancer), diet high in animal fat and a history of benign prostate disease. Some studies have shown associations between greater dietary intake of vitamin A and an excess risk of prostate cancer; other prostate cancer studies suggest that individuals who have had sexually transmitted diseases may be at greater risk. Higher prostate cancer risk also is weakly associated with certain occupations, such as farming, rubber manufacturing, and iron and steel foundry work.
In addition to risk factors, the geographic pattern of prostate cancer in New York State is potentially influenced by many other things, including demographics (Black men have the highest rate of prostate cancer) and prostate cancer screening programs. The Prostate Specific Antigen (PSA) test can identify very early cases of prostate cancer decades before they would otherwise be diagnosed, artificially inflating the incidence rate in parts of the State with active screening programs. Because prostate cancer is slow–growing, there is no clear scientific consensus as to whether early identification of the disease, through screening, produces benefits for all patients. Individuals at risk for prostate cancer are urged to check with their health care provider to determine whether prostate cancer screening is advisable for them.
The ZIP Code maps:
Specifically, the ZIP Code level maps released today show whether the number of new cases of prostate cancer diagnosed within each particular ZIP Code during the years 1994–1998 (the time frame for which the most recent complete Cancer Registry data are available) is higher, lower or about the same as the expected incidence. They also use slanted or crossed lines, called cross–hatching, to identify groups of ZIP Codes which comprise areas where cancer incidence is believed to be elevated. Not all individual ZIP Codes within the cross–hatched areas have higher than expected incidence. Despite these variations, the cancer pattern for an entire region of elevated incidence is considered to be statistically significant.
The ZIP Code level maps are accompanied by an index which lists ZIP Codes in numerical order by county and which provides the actual as well as expected incidence of prostate cancer for each ZIP Code shown. In order to protect patient confidentiality some ZIP Codes (those with very few total cancer cases) were combined with a neighboring ZIP Code before being mapped.
It is important to reiterate that screening patterns almost certainly affect prostate cancer incidence rates. Areas of elevated incidence identified on the maps may have resulted from the occurrence of more PSA testing there, rather than from an actual increase in risk. Areas where fewer men have the PSA test will have lower prostate cancer rates than the State as a whole. The map of prostate cancer incidence depicts five areas of elevated incidence where the observed rate is more than double the expected rate. There also are many areas where the rate is 50 percent to 100 percent greater than expected.
Late stage map:
Because the screening differences make it difficult to use the ZIP Code map of all prostate cancer cases to identify areas where men may be at increased risk of prostate cancer, the Health Department has also produced a map showing where the incidence of late stage prostate cancer is higher than expected. The map compares the rate of late stage prostate cancer in various areas of the State. Screening which identifies disease in the absence of symptoms would not contribute to an increase in the incidence of late stage prostate cancer.
Three areas were identified which have elevated incidence of late stage prostate cancer:
- St. Lawrence County;
- south–central New York State (Chenango and Cortland counties and parts of neighboring counties*); and
- the Crown Heights and Bedford Stuyvesant sections of Brooklyn.
In addition, northern St. Lawrence County, including parts of Potsdam, Waddington and Massena had an elevated incidence rate of late stage prostate cancer that was more than 100 percent above the expected rate.
Men whose prostate cancer is diagnosed at a late stage–after it has spread to other parts of the body–have much higher risk of death. An elevated incidence of late stage prostate cancer in a particular area could indicate either that men living there have a higher risk of prostate cancer than men in other parts of the State, or that they are more likely to have their prostate cancer diagnosed at a late stage, when their chance of survival is poor. Either explanation argues for additional prostate cancer education in such areas.
Unlike the ZIP Code map of all prostate cancer incidence, the late stage map is not color coded. This was done to protect privacy. Since there are only one or two cases of late stage prostate cancer in most ZIP Codes, using color coding on both sets of maps could breach patient confidentiality by making it possible for someone who carefully compared the maps to determine how advanced a specific individual's prostate cancer was at diagnosis.
Racial variation in prostate cancer incidence:
Data from the State's Cancer Registry show that in New York State, as elsewhere in the nation, Blacks have the highest rate of prostate cancer. Because of this, ZIP Code maps of all prostate cancer incidence and the late stage map were designed to take into account racial variation within New York State. The race of men in each ZIP Code was considered in calculating how many cases of prostate cancer would be expected to occur there, a process known as "race adjustment." To further explore racial patterns of prostate cancer across New York State, the State Health Department today also released two additional prostate cancer maps One map illustrates the geographic pattern of prostate cancer incidence among Black men; the other depicts incidence among whites.
New York State does not have a large rural Black population. This is evidenced by the number of counties where the average number of Black men diagnosed with prostate cancer is fewer than one per year. In counties where the average number of Black men diagnosed with prostate cancer is more than one per year, the incidence rate for Black men tends to be higher than that for white men. The lowest prostate cancer rates are seen among white men residing in the New York City area and some rural areas of the State.
The Department will conduct an educational campaign to alert men over 50 about the importance of prostate cancer awareness, and to urge them to check with their doctor to determine whether they should get PSA screening. Although the awareness campaign will be mounted throughout the State, special emphasis will be placed on areas where the rate of late stage prostate cancer is highest.
Dr. Novello will also send a letter to physicians asking them to talk to their patients about prostate cancer, including risk factors and considerations for screening. In addition, the Commissioner has contacted Chief Executive Officers of hospitals in areas of elevated late stage prostate cancer incidence and will work with them to arrange for prostate cancer education and screenings days early in 2002.
Additional prostate cancer initiatives and information:
The New York State Department of Health, along with the SUNY Albany School of Public Health, has been awarded a three–year grant totaling more than $650,000 to support the production of these prostate cancer incidence maps, along with maps showing prostate cancer mortality in New York. The grant award, from the Association of Schools of Public Health, also will support research to examine data about prostate cancer risk factors and whether and how proximity to tertiary care hospitals or other specialized medical treatment is related to increased prostate cancer incidence and mortality rates.
The prostate cancer maps released today are posted on the State Health Department's web site (www.health.state.ny.us) along with information about the purposes of the Cancer Surveillance Initiative; general facts about cancer, its known causes and prevention; facts about prostate cancer; and how to read the maps and accompanying ZIP Code index. A hard copy version of the ZIP Code level prostate cancer maps will be available in the future. Previously produced cancer maps also are available via the website.
*Individuals may refer to the Department's web site for a complete list of the referenced counties.