The effects of the Union for International Cancer Control/American Joint Committee on Cancer Tumour, Node, Metastasis system version 8 on staging of differentiated thyroid cancer: a comparison to version 7.

TNM 8 results in a marked downstaging of patients compared to TNM 7. Although some changes, like the change in age boundary, appear to be associated with an improvement in prognostic power, the overall effect of the changes does not improve the predictive power compared to TNM 7.