R classification

The R classification is a facet classification from medicine and denotes a characteristic classification of malignant tumors (cancer diseases).

The letter "R" stands for "Residual" (lat. residuus: remaining). The absence or presence of residual tumor after therapy is described by the R-classification:

The R classification has two facets. It was originally conceived as a prognostic factor for overall survival after therapy and was described as such in the TNM system. Any remaining tumor must be considered after therapy.

If, for example, the patient has a liver metastasis, but in the operation, but only the primary tumor (with lymph nodes) has been completely removed, this definition still has a R2 situation despite tumor-free cut edges

However, since the pathologist evaluating a surgical preparation can only assess what he sees, he will in this case still choose R0 as the result. Given the fact that this is a prognostic factor for the recurrence of a local recurrence, this is also necessary.

For this reason, according to the current recommendation of the TNM system, the "R" must always be specified so that the data can be handled correctly in evaluations.

An R0 indication is also possible if, after systemic and radiation therapy, the tumor is no longer detectable, subject to certain rules, For example, if there is no evidence for residuals in the case of a tumor resected originally in the region of R1 after completion of post-irradiation in bioptic and / or imaging methods Edit source text

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