About the cancer data

This page provides general information about the cancer data and measures developed by the Minnesota Environmental Public Health Tracking (MN EPHT) Program. For more information about these data, contact MNPH Data Access.

  • The incidence of cancer in Minnesota residents by year.
  • The incidence of some cancers in Minnesota residents by age group, race/ethnicity, gender, or region of the state.
  • If a measure is going up or down over time.
  • If a segment of a population is at higher risk for cancer or a specific type of cancer.
  • To inform the public about cancer incidence in Minnesota.
  • For program planning and evaluation by state and local partners.
  • What causes cancer or what causes specific types of cancer.
  • Cancer incidence data is collected by the Minnesota Cancer Surveillance System (MCSS), an ongoing program at the Minnesota Department of Health (MDH) and Minnesota's central cancer registry.
  • The completeness and quality of MCSS data has been audited by CDC's National Program of Cancer Registries (NPCR). MCSS data are complete and of high quality.
  • Data on colorectal cancer screening coverage comes from the U.S. Behavioral Risk Factor Surveillance System (BRFSS).
  • MCSS collects information on microscopically-confirmed malignant and most in situ tumors. MCSS does not count clinically-diagnosed cancers that a physician diagnoses using other medical equipment (e.g., MRI or chest X-ray) without microscopic confirmation of a tissue sample.
  • For brain, liver, and pancreatic cancer: unlike other state or regional cancer registries, from 1988-2011 the Minnesota Cancer Surveillance System (MCSS) only counted cancers that were microscopically confirmed. Rates in Minnesota may not be comparable to rates in other states that count these cancers diagnosed without tissue confirmation. Beginning in 2012 MCSS started collecting data on cancers that were clinically diagnosed (radiography, CAT scans and MRIs). The increase in rates in 2012 for these cancers are due to the collection of clinically-diagnosed cancers.

Number:

  • The number indicates the total number of cancer cases.
  • To understand the magnitude or how large the overall burden is, use the number.
  • To protect an individual's privacy, cancer counts are suppressed if the underlying population is less than or equal to 1,000 or the underlying population of children is less than or equal to 10,000. The number may also be suppressed due to complementary suppression or in a situation where the total number of all types of cancers for a region is less than 20 and within those twenty cancers, a few cancer types account for many of the total number of cancers.

Rate:

  • A rate is a ratio between two measures with different units. In our analysis, a rate is calculated using a numerator, the number of cancer cases during a period of time, divided by a denominator, the number of people at risk in a population during the same period of time. This fraction is then multiplied by a constant (in this case 100,000) to make the number more legible. Population estimates from the U.S. Census Bureau are used to calculate the rate. To understand the probability or what the underlying risk in a population is, use a rate.
  • To avoid misinterpretation of unstable rates, rates based on less than 10 cases of cancer are marked as unstable or "(UR)" when querying data.

Age-adjusted rate:

  • An age-adjusted rate is an overall summary measure that helps to control for age differences between populations. A weighted average, called the "direct method," is used to adjust for age in this analysis. Age specific rates in a given population are adjusted to the age distribution in a standard population by applying a weight. The U.S. 2000 standard population is used as the basis for weight calculations.
  • Age-adjusted rates are useful when comparing the rates of two population groups that have different age distributions.
  • Regional displays of cancer data on MNPH Data Access categorize MN counties by regions designated by the State Community Health Services Advisory Committee or SCHSAC (see map of Minnesota Counties by SCHSAC Regions). There are minor differences between SCHSAC regions used here and regions used in past MCSS publications. Future MCSS publications will use the SCHSAC region scheme, which categorizes Becker, Meeker, and McLeod counties in different regions.
  • MCSS data is dynamic and subject to change when appropriate; data are always being updated and improved. Cancer incidence data currently displayed on MNPH Data Access were considered accurate as of the analysis date.
  • For brain, liver, and pancreatic cancer: unlike other state or regional cancer registries, from 1988-2011 the Minnesota Cancer Surveillance System (MCSS) only counted cancers that were microscopically confirmed. Rates in Minnesota may not be comparable to rates in other states that count these cancers diagnosed without tissue confirmation. Beginning in 2012 MCSS started collecting data on cancers that were clinically diagnosed (radiography, CAT scans and MRIs). The increase in rates in 2012 for these cancers are due to the collection of clinically-diagnosed cancers.
  • A small number of cancer cases among Minnesota residents are missing "county of residence" and are therefore classified as "unknown" county. Because of this, it's possible for the sum of the number of new cancers for all Minnesota counties (combined) may not match the total number of new cancers at the state-level for a specific cancer type.
  • Rates based on 10 or fewer cases of cancer are unstable (i.e. unstable rate or UR) and caution should be exercised in interpreting these rates.
  • Counts presented here are number of cancers, not number of people with cancer. A person can contribute more than one case of cancer for the purposes of these data.
  • Race/ethnicity data are difficult to collect accurately and in a manner consistent with U.S. Census data, which is used for calculating age-adjusted incidence rates. Active follow-up measures to determine race/ethnicity are used by MCSS; see the MCSS publication Cancer in Minnesota 1998-2008 (see pp. 24-28) for more information on active follow-up measures. Nonetheless, an unknown degree of misclassification likely exists in the race/ethnicity data. There are two different methods used by MCSS to determine American Indian cancer incidence rates. One of those methods is used on this website. The alternative method of displaying American Indian cancer incidence rates is described in Minnesota Cancer Facts & Figures 2015 (see pp. 7-8).
  • Race/ethnicity data: The category of black race is named differently among different hospital records that report cancer incidence data. The category is presented in these pages as "black" but could also be referred to as "black or African-American" in some hospital records.

Average annual percent changes in trends are calculated using Jointpoint Trend Analysis Software.

The Minnesota Cancer Surveillance System (MCSS) has additional resources, including surveillance reports and more information on case ascertainment and quality control. To learn more about the cancer data and measures, contact MNPH Data Access.