Collaborative Stage (CS) was collected in the U.S. and Canada from 2004-2015, though some registries continued to collect CS through 2017. Collaborative Stage was a unified data collection system that was designed to provide a common data set to meet the needs of all three staging systems: TNM, SEER Extent of Disease (EOD), and SEER Summary Stage (SS). It provided a comprehensive system to improve data quality by standardizing rules for timing, clinical and pathologic assessments, and compatibility across all of the systems for all cancer sites. The Collaborative Stage project was sponsored by the American Joint Committee on Cancer (AJCC) in collaboration with several standard-setting organizations, including the SEER Program. The SEER Program developed training resources and software related to the implementation of Collaborative Staging in cancer registries.
Collaborative Stage Data Collection System - The main CS web site that includes coding instructions, software, and education and training resources.