Diagnosis Staging

When the consultant identifies a bowel cancer they will give a formal diagnosis. The key part of this is the staging. This describes the extent to which the cancer has developed.

The staging appears as a series of letters and numbers, eg pT3 N1a M0 V1 R0

It is important to understand your diagnosis. The links listed below will help you. No one site gives you all of the information, but between them you can learn about the TNM staging system and its nuances. The Radiopaedia pages are especially useful for understanding the prefixes and suffixes.

Note: The diagnosis will often contain additional information from histology or pathology describing the genetic aspects of a tumour and your genome. Please go to our Biomarkers page for more information about these.

Residual Tumour Classification

R0 > 1 mmNo residual tumor, minimal distance between tumor and resection margin; margin ≥1 mm
R1 ≤ 1 mmNo residual tumor, minimal distance between tumor and resection margin; margin ≤1 mm
R1-dirMicroscopic residual tumor, tumor directly at the resection margin (tumor transected)
R2aLocal macroscopic residual tumor
R2bDistant macroscopic residual tumor
R2cMacroscopic residual tumor in both sites

A uniform residual tumor (R) classification – Scientific Paper

Detailed Explanation of Cancer Staging – Download PDF