Y symbol
If a tumor is particularly large, in some cases it is treated chemotherapeutically or irradiated before surgery. This is intended to reduce the size and spread of the tumor and make the operation easier or even possible in the first place. In order to differentiate between the spread of the tumor before treatment and before surgery, a ” y” is added to the TNM classification (TNM system) after chemotherapy.
R symbol
If a tumor was initially successfully treated but recurs after some time, it is a recurrence. In order to be able to distinguish between the original tumor disease and the recurrence, an “r” is added to this TNM classification (TNM system).
Residual tumor
The residual tumor indicates whether or not tumor tissue has remained in the body after surgery and removal of the primary tumor. R0 is usually the desired final state of an operation. In the case of R1, resection is often performed to remove the remaining tumor cells from the cut edges.
In the case of R2, palliative surgery is often performed to improve the patient’s quality of life, but there is no prospect of cure. In such cases the tumor disease is very advanced.
- R0: no detectable residual tumor in the tissue
- R1: microscopic detection of tumor cells at the edges of the cut
- R2: macroscopically visible tumor or metastases remain in the body
Grading
- G1: Well differentiated tissue, which is still very similar to the original organ tissue.
- G2/3: increasingly poorly differentiated tissue.
- G4: very poorly differentiated tissue, which no longer has any similarities with the actual organ tissue
