NAACCR receives de-identified, population-based cancer data from member registries across the United States and Canada. With permission from the registries, NAACCR combines the cancer incidence data from submitting registries into comprehensive datasets for analysis. These Cancer in North America (CiNA) datasets only include data from registries that meet NAACCR standards for completeness and quality. Researchers may request access to the CiNA datasets, irrespective of their affiliated institution’s geographic location.

Requirements for data access vary by product and, at a minimum, include a signed Data Use or Data Assurance agreement. Depending on the dataset, additional requirements may include working with a NAACCR member, having approval from the NAACCR Research Application Review (RaPR) committee, and being a SEER institutional account holder.

CiNA DATA PRODUCTS: Supported by NAACCR

• CiNA Explorer is an on-line, publicly accessible, interactive data visualization tool for quick access to cancer incidence statistics for major cancer sites.
  • CiNA Explorer

• CiNA Maps is an on-line, publicly accessible, interactive mapping tool for quick access to cancer incidence statistics for major cancer sites for the most recent five years.
  • CiNA Maps

• CiNA Public Use Dataset is a publicly accessible incidence dataset with limited data variables requiring only a signed Data Assurance Agreement for access.
  • Data are released via SEER*Stat.
  • More information about the CiNA Public Use Dataset.
  • Request access to these data via the Public Use Research File option in NAACCR’s Data Request Tracking (DaRT) system (requires a free MyNAACCR account)

• CiNA Research Dataset is a de-identified incidence, survival, or prevalence dataset that may be used to conduct research. Proposals must be reviewed and approved by NAACCR, and individual registries must consent to participate before any research datasets are released. Researchers outside of central cancer registries may obtain data, as long as they have a NAACCR member collaborator. Data are released via SEER*Stat and require a SEER institutional account.
  • More information about the CiNA Research Dataset
  • Request access to these data via the CiNA Dataset for Researchers option in DaRT (requires a free MyNAACCR account)

Delay Adjustment Factors and Rates

State-Level Delay Adjustment Factors are available to registry personnel for their own state as a Registry-Specific Dataset. National-Level Delay Adjustment Factors are available for research as a special request CiNA Dataset through DaRT . Learn more.

We encourage registries to evaluate their state-specific delay adjustment factors and rates. To obtain access to the delay adjustment data for your state in SEER*Stat, please use DaRT.

To request any of the CiNA Datasets, including registry-only products such as delay-adjusted, please use DaRT, the NAACCR Data Request Tracking system.

Cancer Coding Changes Over Time

Changes in definitions for site, histology, behavior and stage occur over time. These changes are important to consider when interpreting trends or significant differences by year. When evaluating trends, it is critical to not only use the delay adjusted rates when available, but also to compare data from years in the most compatible way possible. There are a number of recodes available in the research datasets (stage, behavior, site) that assist with this because they take into account changes over time. However, there are coding changes that may impact specific sites that are not handled by currently available recodes. Analysts and researchers must collaborate with registry staff to understand how coding or other operational issues may be driving trends.

To ensure trends are appropriately interpreted, it is critical to review any new or large changes in trends. Coding changes, clinical advancements (e.g. biomarker and screening tests), and progress in pathologic classification can all contribute to dramatic changes in cancer rates that do not reflect a true change in underlying burden of cancer. Below are some important examples, but analysts and researchers need to work with an ODS-C or registry staff familiar with coding over time to ensure cancer statistics are interpreted correctly over time.  Researchers should use the NAACCR Implementation Guidelines to evaluate whether any new or unexpected trends may be the results of coding changes.

Stomach Cancer

The 2025 Annual Report to the Nation reported that the largest observed increase in cancer among women for five-year trends was stomach cancer. This was a new and unexpected statistic. However, this likely reflects changes in disease classification rather than a true change in the underlying burden of the disease. In 2021, there was a change in the WHO ICD-O-3 classification of tumors impacting gastrointestinal stromal tumors (GISTs). GISTs are rare cancers commonly diagnosed in the stomach; and, historically, most GISTs were classified as nonmalignant. However, based on increased understanding of these unique tumors, the WHO classification now considers all GISTs to be malignant unless specifically stated otherwise by the pathologist. Because cases of stomach cancer are rare, the addition of these GISTs into the numerator increased rates, which is now echoed in the increasing AAPC for stomach cancers. For now, we can interpret the rising stomach cancer rates similarly to a screening effect. The rates are a better picture of cancer burden, but there is no underlying increase in risk.

Childhood Cancers

For pediatric cancers, differences in incidence rates may be due to changes between the second and third edition of the International Classification of Childhood Cancers (ICCC) in 2005. Two changes in the ICCC-3 classification are main contributors to this change.

1.      Burkitt lymphoma and unspecified lymphoma, which were separated from non-Hodgkin lymphoma previously are combined with non-Hodgkin lymphoma;

2.      Some lymphomas, which were grouped in the miscellaneous lymphoreticular neoplasms previously, are now included in the non-Hodgkin lymphoma category.

Transition to ICD-O-3

Several definitional changes occurred in some histology and behavior codes with the transition to ICD-O-3 that affected the inclusion and exclusion of reportable cancers diagnosed beginning in 2001.The changes predominately affected leukemias, lymphomas, and cancer of the ovary. One category of change between ICD-O-2 and ICD-O-3 is the manner in which leukemias and lymphomas are classified and coded. Although conversion of histology codes from ICD-O-2 to ICD-O-3 for cases diagnosed prior to 2001 helps minimize these differences, some minor differences may still exist, particularly with respect to some relatively rare lymphocytic cancers that can be coded to either leukemia or lymphoma.

Starting with ICD-O-3, several myelodysplastic diseases and syndromes are considered malignant, and, therefore, are now reportable for cases diagnosed in 2001 and later and are included in these data. Leukemias that represent disease progression from one of the myelodysplastic diseases or syndromes diagnosed in 2001 and forward are no longer reportable.

Pilocytic astrocytoma is considered to have uncertain behavior in the published version of ICD-O-3 but is reportable as a malignant cancer in North America. Including the childhood astrocytomas in the category of malignant brain tumors may introduce differences between childhood brain cancer rates in North America compared to other areas of the world that may not include these tumors as malignant.

In addition, mesothelioma and Kaposi sarcoma cases are reported as separate categories. This change has little or no impact on most rates for specific cancers.