Table 6.
Tumor Regression Grade | Histopathological findings |
---|---|
Grade 0: | No regression. |
Grade 1: | Minor regression, residual tumor outgrowing fibrosis. |
Grade 2: | Moderate regression, low tumor cell fibrosis in 26% to 50% of the tumor mass. |
Grade 3: | Major regression, very few tumor cells in fibrotic tissue with or without mucous substance. |
Grade 4: | Total regression, no viable tumor cells, only fibrotic mass. |
Tumor regression grade (TRG) system according to Dworak et al.