Speaker
Description
Cancer stage at diagnosis is an important prognostic factor to assess the effectiveness of cancer clinical management and treatment. The two most used staging system by population-based cancer registries (PBCR) are TNM staging classification and the SEER summary (SS) staging or local variation of the SS. The lack of international standardization for recording stage information, the frequent changes in staging classification systems, and differences in completeness of stage information between PBCRs are some of the biggest challenges to international comparisons of stage-specific cancer survival estimates. The availability and comparability of staging information for colorectal, lung, female breast and ovarian cancer were previously assessed by the International Cancer Benchmarking Partnership (ICBP) Phase I. In this study, we aim to evaluate the completeness of stage information for esophageal, stomach, and pancreatic cancers by PBCRs from 1995-2014, and present stage conversion algorithms for these three cancer sites. Although these stage conversion approaches could be used to assess stage-specific survival between PBCRs, additional actions are needed to resolve the challenges we face in stage-specific survival comparisons globally. Consequently, we also aim to discuss recommendations for cancer registries to help improve international cancer survival comparison by stage: 1) Improve collection and completeness of staging data; 2) Promote a comparable definition for stage at diagnosis; 3) Promote the use of a common stage classification system; 4) Record versions of staging classifications; and 5) Use multiple data sources for valid staging.
