The recent revised edition of the American Joint Committee on Cancer staging for gallbladder cancer involved several major changes.
T2N0M0 tumors were moved from stage II to stage IB, T3N1M0 disease was moved from stage III to stage IIB and T4NxM0 tumors were moved from stage IVA to stage III.
To determine whether these changes were justified researchers analyzed data from 10,705 cases of gallbladder cancer.
All patients had more than 5 years of follow-up.
The team found that the staging in the revised edition provided no discrimination between stage III and IV.
|The revised edition provided no discrimination between stage III and IV.|
|Annals of Surgery|
They determined that 5-year survivals for stage IIA, IIB, III, and IV were 7%, 9%, 3%, 2% respectively.
The researchers used the data from the National Cancer Database to derive a proposed new staging system that built on the previous editions.
They were able to improve discrimination of stage groups over previous editions.
Dr Yuman Fong's team concluded, "Changes in staging systems should be justified by data".
"Multicenter databases, including the National Cancer Database, represent important resources for verification of evidence-based staging systems".