Map Tracks Incidences of Cancer Throughout New York State

ALBANY — New York unveiled what it billed as the nation’s first comprehensive statewide cancer map, which became available Monday on the Web site of the State Department of Health.

Not that the Health Department is doing so eagerly. The creation of the map was opposed by both the department and the American Cancer Society when it was proposed two years ago, according to a review of state records, amid concerns that its unfiltered data could be misinterpreted.

State officials were forced to create the map when the Legislature voted in support of it, and Gov. David A. Paterson sided against his own administration in signing the legislation.

The interactive map allows users to see the count of incidences of various types of cancer in different census blocks, which can number in the thousands of people in New York City or fewer than a hundred in upstate counties. For instance, randomly highlighting a four-square-block chunk of Brooklyn, between Henry and Court Streets and Second and Fourth Places, shows 23 cases of cancer out of 1,195 residents, with pancreatic and uterine cancers the most prevalent.

The map also allows users to overlay potentially hazardous sites nearby, including brownfields, superfund sites or buildings in which chemicals are stored. The sponsors of the legislation that created the cancer map argue that the public should be allowed access to the information, since it is compiled by the state. But they repeatedly cautioned that it represents raw data, merely presenting a count of cancer incidences, and should be interpreted with care.

For instance, if the map were oriented on top of a nursing home, it would be expected to show a higher than normal instance of cancer, but it would not represent some kind of “cancer cluster.” There is also no adjustment for the age of the population or a number of other factors, like whether cases of lung cancer were attributable to environmental factors or smoking.

“This is Step 1 in a process which over the course of months and years will yield a conclusion about where cancer clusters exist in New York,” said Assemblyman Richard L. Brodsky, a Westchester Democrat who sponsored the mapping legislation, calling it a “first step in getting to answers about whether these clusters are statistical accidents or related to an environmental cause.”

The American Cancer Society initially opposed the legislation, writing in a 2008 letter to the governor’s office that “giving people potentially misleading information about the relative danger or safety of living or working in a specific neighborhood or region is no service to them.”

But David Momrow, a senior vice president at the society, said on Monday that recent tweaks to the legislation had allayed their concerns, particularly explanations included on the new Web site “about the qualifications or limitations of reading a map and being cautious in your interpretation.”

Claudia Hutton, director of public affairs for the Health Department, said, “We felt an overlay of environmental-type facilities with new cancer cases might lead people to make incorrect conclusions,” adding that, “to be most useful to the public, health information needs to be provided with context.”

Mr. Brodsky disagreed.

“You bump against this question again and again: Should the government trust the people enough to tell them the truth?” he said. “The time when you could trust the government to say, ‘Trust me I know best’ is long past.”

Senator Tom Libous, a Republican of Binghamton who sponsored the legislation in the Senate said, “We believe this is good, solid public health policy, that people should have this information.”

The state Division of Budget previously forecast that creating and maintaining the map would cost about $3.2 million a year, though it was done within the Health Department’s existing budget. The map was compiled using 2000 census data and cancer diagnoses from 2003 to 2007. Upstate, particularly small census blocks were sometimes combined, to protect patient privacy.

The Health Department is working on a next step that will try to identify anomalies where high incidences of cancer legitimately do exist, and it hopes some of those results will be available this year.