Mode of Collection:
Cancer registries collect and report new cases of cancer, and follow-up information on previously-reported cases, to the National Cancer Institute.
Patient demographics, primary tumor site, morphology, stage at diagnosis, first course of treatment, and follow-up for vital status.
The 17 population-based cancer registries currently reporting SEER data cover approximately 26% of the U.S. population.
A cancer registry collects and stores data on cancers diagnosed in a specific medical facility (hospital-based registry) or in a defined geographic area (population-based registry). In SEER registry areas, trained coders abstract medical records using International Classification of Diseases for Oncology, third edition (ICD-O-3). which provides a coding system for site and tumor morphology. U.S. Census Bureau population estimates (supplemented by National Cancer Institute-produced estimates) are used to calculate incidence rates.
Response Rates and Sample Size:
Because of the addition of registries over time, analysis of long-term incidence and survival trends is limited to those registries that have ben in SEER for similar lengths of time. Analysis of Hispanic and American Indian and Alaska Native data is limited to shorter trends.