Pathology, tumour staging, and prognostic and predictive biomarkers

Abstract The whole basis of optimal diagnosis and treatment of colorectal cancer depends on high-quality, accurate pathology to assess the tumour staging and to evaluate prognostic markers. First, primary tumours of other organs can deposit on the serosa of the bowel and can be confused with primary bowel cancer so accurate diagnosis of the primary characteristics is crucial so that the correct treatment can be applied. Also, accurate pathological staging (tumour and nodal status) allows the clinician to inform the patient of the true balance of risks and benefits of any adjuvant treatment that is offered and also informs the follow-up care and monitoring that is required.