Environmental Public Health Tracking: Cancer Data

Cancer begins in cells, the building blocks that make up tissues. Tissues make up many parts of the body. When new cells form that the body doesn't need and old or damaged cells don't die as they should, the cells form a mass of tissue called a lump, growth, or tumor.

Tumors in the body can be benign (not cancer) or malignant (cancer). Benign tumors are not as harmful as malignant tumors. The benign tumors can often be removed and usually don't grow back or spread to other parts of the body. The malignant tumors may be life-threatening and can often be removed but sometimes grow back. These tumors can invade and damage nearby tissues and spread to other parts of the body.

Learn more about cancer on the Cancer Facts and Cancer Clusters webpage.

There is evidence of a link between cancer and environmental pollutants. Coming in contact with some things that cause cancer is potentially avoidable. For example, tobacco smoking can be avoided with behavioral changes.

Although environmental pollution has been a source of public concern for decades, there have only been a few well-studied cases of environmental exposures at the community-level. The cancer risks associated with many environmental chemicals are based on studies in the workplace, where exposures are often much greater than they would be in the general public. These earlier studies provide the foundation for building evidence that supports a link between cancers and exposures to environmental pollutants.

Other environmental factors are less controllable, such as cancer-causing materials released into the air. Some risk factors are unavoidable, such as age, race, or genetics. It is important to remember having a risk factor increases the chances a person will develop cancer, it does not mean the individual will for sure develop cancer. Many people who develop cancer do not have many or any of the currently known risk factors.

The portal provides data from the Wisconsin Cancer Reporting System, which is maintained by the Office of Health Informatics, Wisconsin Department of Health Services.

We track cancers that were selected by a national workgroup based on the following criteria:

• Scientific basis for environmental risk factors
• Geographic variability or temporal trend in cancer incidence
• Short latency cancer
• Attributable risk
• Feasibility of obtaining relevant environmental data
• Possibility of public health or environmental intervention
• Frequency (incidence rate)

We host data on the following cancers:

• Bladder
• Brain and Central Nervous System
• Breast
• Colon and Rectum
• Esophageal
• Kidney and Renal
• Laryngeal
• Liver
• Leukemia (Acute and Chronic Lymphocytic, and Acute Myeloid)
• Lung
• Melanoma
• Mesothelioma
• Non-Hodgkin Lymphoma
• Oral Cavity and Pharyngeal
• Pancreatic
• Testis
• Thyroid

For each type of cancer, users are able to view counts and the age-adjusted rate.

Dynamic reporting of cancer data

The Wisconsin Cancer Reporting System (WCRS) cancer incidence data are dynamic, meaning they are continuously updated as new cases are reported, existing records are corrected, and additional information becomes available. WCRS follows national standards for quality and completeness, ensuring that finalized data are reliable and suitable for surveillance and public report.

For public data query systems like EPHT Cancer Data, cancer incidence data are frozen and published annually to create a stable, consistent dataset for comparison across years. The annual freeze ensures that data users are working with a standardized version of the data. However, because cancer incidence data are dynamic, data users should keep in mind that counts and rates for the most recent diagnosis years may be underestimates and should be interpreted with caution. Reporting lag adjustments happen every year, meaning some counties may see changes in recent diagnosis years as additional late-reported cases are sent to WCRS.

If you or your team saved earlier versions of cancer incidence data for reports for local use from EPHT Cancer Data, we strongly encourage you to use the most recently published data to ensure accuracy and consistency with current methods.

Impact of COVID-19 on data

The EPHT Cancer Data include cancer cases diagnosed in 2020 and 2021, the first and second years of the COVID-19 pandemic. The COVID-19 pandemic disrupted health services, leading to delays and reductions in cancer screening and diagnosis. This may have contributed to lower incidence for most cancer sites in 2020. The number of new cases diagnosed in 2021 are still a little lower for some cancer types but have returned to pre-pandemic counts for other cancer types.

Data users should acknowledge COVID-19 impacts on cancer incidence data when querying 2020 and 2021 diagnosis years.

Race and ethnicity coding

Race and Hispanic ethnicity information available in EPHT Cancer Data are primarily based on information collected at diagnosis, typically from medical records. This means they often reflect health care records or patient self-report when available, but consistency and completeness can vary. To improve accuracy and standardization:

• The Indian Health Service (IHS) linkage helps identify American Indian/Alaska Native individuals more accurately. This is done by linking cancer registry records with the IHS patient registration database to catch cases where American Indian/Alaska Native identity might not have been recorded in the medical record.
• The NAACCR Hispanic Identification Algorithm (NHIA) is used to enhance identification of Hispanic ethnicity. NHIA uses factors like surname, birthplace, and race/ethnicity information to more reliably assign Hispanic origin, especially when it's missing or ambiguous.

Data users should be cautious when interpreting race and ethnicity data due to potential misclassification and underreporting, particularly for American Indian/Alaska Native and Hispanic populations.

Geographic considerations

Data users should be aware that geographic boundaries can affect cancer case ascertainment and data completeness. For example, underreporting from Minnesota facilities can lead to incomplete data for Wisconsin residents diagnosed or treated across the border, particularly in counties in the Western Division of Public Health Region. This can result in lower than expected case counts and rates in those areas.
Additionally, smaller counties may show large fluctuations in incidence rates year to year, due to the small number of cases. This can make it difficult to interpret changes over time reliably.

Data users should interpret differences in cancer incidence rates between regions and counties with caution, especially when analyzing small populations or areas along state borders.

Coding changes over time

When using these modules, be aware of key coding updates implemented that may affect counts and rates over time:

• 2000: Cancer registries transitioned from ICD-O-2 to ICD-O-3 coding standards. This change impacted how certain cancers, particularly cervical, bladder, and hematopoietic cancers were classified. Users should interpret changes in incidence counts and rates around 2000 with caution, as changes may reflect coding updates.
• 2004: Cancer registries began collecting information on non-malignant brain and other central nervous system tumors in accordance with Public Law 107-260, the Benign Brain Tumor Cancer Registries Amendment Act.
• 2007: New criteria were applied for determining when tumors are counted as new primaries (a new instance of cancer). This affected case counts and rates by site marginally. For more information, visit SEER Training Major Changes.
• 2010: Select lymphoma and leukemia ICD-O-3 codes were updated based on changes by the World Health Organization. Some cancers previously categorized as non-malignant or pre-malignant are now considered malignant and reportable. Therefore, the counts for total cancers in Wisconsin are higher for years covered by ICD-O-3 due to changes in reporting requirements.

Data users should interpret data over time with these changes in mind and consider focusing on consistent coding eras for more accurate comparisons.

Interpretation of cancer risk

Data users should keep in mind that many factors contribute to cancer risk. These factors should be considered when interpreting the data. Factors include:

• Demographics (race, gender, age)
• Socioeconomic status (income level, education)
• Geography (rural, urban)
• Changes in the medical field (diagnosis patterns, reporting requirements)
• Individual behavior (diet, smoking, physical activity levels)

Suppression

Data for counties with fewer than six cases are suppressed to protect confidentiality. However, counties with zero cases are not suppressed.

• Wisconsin Cancer Reporting System
• National Cancer Institute
• Centers for Disease Control and Prevention - Tracking and Cancer
• Surveillance Epidemiology End Results

Select the link below to download the data you're looking for:

• County data (CSV)
• State data (CSV)

All cancers

Note that overall reports of cancer cases dropped sharply for 2020. Cancer rates change from year to year because of changes in exposures to risk factors, screening test use, diagnostic practices, and treatment. Some changes in 2020 may also be due to disruptions in cancer care caused by the COVID-19 pandemic, including reduced access to routine care, postponed or deferred health care visits, and delayed reporting of cancer cases due to disruptions in registry operations.

Bladder cancer

• Number of new bladder cancer cases: all ages: Counts of new bladder cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of bladder cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of bladder cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the brain and central nervous system

• Number of new brain and central nervous system cancer: ages 0-19: Counts of new brain and central nervous system cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of brain and central nervous system cancer per 1,000,000 people: ages 0-19: Incidence rates are calculated from the annual number of new cases (counts) of cancer of the brain and central nervous system reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.
• Number of new brain and central nervous system cancer: all ages: Counts of new brain and central nervous system cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of brain and central nervous system cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of cancer of the brain and central nervous system reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the colon and rectum

• Number of new colon and rectal cancer cases: all ages: Counts of new colon and rectal cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of colon and rectal cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of colon and rectal cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the esophagus

• Number of new esophagus cancer cases: all ages: Counts of new esophagus cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of esophagus cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of esophagus cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Female breast cancer

• Number of new female breast cancer cases: ages 0-49: Counts of new female breast cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of female breast cancer per 100,000 people: ages 0-49: Incidence rates are calculated from the annual number of new cases (counts) of female breast cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.
• Number of new female breast cancer cases: ages 50+: Counts of new female breast cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of female breast cancer per 100,000 people: ages 50+: Incidence rates are calculated from the annual number of new cases (counts) of female breast cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Kidney and renal pelvis cancer

• Number of new kidney and renal pelvis cancer cases: all ages: Counts of new kidney and renal pelvis cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of kidney and renal pelvis cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of kidney renal and pelvis cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the larynx

• Number of new larynx cancer cases: all ages: Counts of new larynx cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of larynx cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of larynx cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Leukemia

• Number of leukemia: ages 0-19: Counts of new leukemia cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence leukemia per 1,000,000 people: ages 0-19: Incidence rates are calculated from the annual number of new cases (counts) of leukemia reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.
• Number of leukemia: all ages: Counts of new leukemia cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of leukemia per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of leukemia reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Acute lymphocytic leukemia

• Number of acute lymphocytic leukemia: all ages: Counts of new acute lymphocytic leukemia cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of acute lymphocytic leukemia per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of acute lymphocytic leukemia reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Acute myeloid leukemia

• Number of acute myeloid leukemia: all ages: Counts of new acute myeloid leukemia cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of acute myeloid leukemia per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of acute myeloid leukemia reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Chronic lymphocytic leukemia

• Number of chronic lymphocytic leukemia: all ages: Counts of new chronic lymphocytic leukemia cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of chronic lymphocytic leukemia per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of chronic lymphocytic leukemia reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Lung and bronchus cancer

• Number of new lung and bronchus cancer cases: all ages: Counts of new lung and bronchus cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of lung and bronchus cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of lung and bronchus cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Liver cancer

• Number of new liver cancer cases: all ages: Counts of new liver cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of liver cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of liver cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Non-Hodgkin's Lymphoma

• Number of new Non-Hodgkin's Lymphoma cases: all ages: Counts of new non-Hodgkin's lymphoma cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of Non-Hodgkin's Lymphoma per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of non-Hodgkin's lymphoma reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Melanoma

• Number of new melanoma cases: all ages: Counts of new melanoma cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of melanoma per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of melanoma reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Mesothelioma

• Number of new mesothelioma cases: all ages: Counts of new mesothelioma cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of mesothelioma per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of mesothelioma reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the oral cavity and pharynx

• Number of new oral cavity and pharynx cancer cases: all ages: Counts of new oral cavity and pharynx cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of oral cavity and pharynx cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of oral cavity and pharynx cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Cancer of the pancreas

• Number of pancreatic cancer cases: all ages: Counts of new pancreatic cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of pancreatic cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of pancreatic cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Testicular cancer

• Number of new testicular cancer cases: all ages: Counts of new testicular cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of testicular cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of testicular cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.

Thyroid cancer

• Number of thyroid cancer cases: all ages: Counts of new thyroid cancer cases are reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin for a given year.
• Age-adjusted incidence rates of thyroid cancer per 100,000 people: all ages: Incidence rates are calculated from the annual number of new cases (counts) of thyroid cancer reported to the Wisconsin Cancer Reporting System by health care providers in Wisconsin during a given year. Direct age-adjustment is conducted using the 2000 U.S. standard population.