There is inconsistency over the histological grading of colorectal carcinoma. The U.K. Co-ordinating Committee on Cancer Research's Sub-Committee on Colorectal Cancer Staging recommended that only 'poor' or other grade tumours be defined.
Mucinous tumours, i.e. > 60% mucin, tend to occur in younger patients, are more likely to be advanced and fixed, and are more proximally distributed in the colon.
The presence of an expanding or infiltrating margin should be recorded, as should lymphocyte infiltration and relative aneuploidy - detected with flow cytometry. An infiltrating, aneuploid tumour carries a worse prognosis.
The presence of a high tumour concentration of urokinase-type plasminogen activator, a protease involved in cancer metastasis, has been highly correlated with poor long term survival.
Last reviewed 05/2019