How to measure tumour response in rectal cancer? An explanation of discrepancies and suggestions for improvement

In the 1990s preoperative radiotherapy and chemoradiation (CRT) were administered in a range of tumours with the aim of reducing tumour volumes to enhance operability prior to definitive surgical intervention. Attempts to show a distinction between responders and non-responders by grading the pathological effects of preoperative CRT treatment originated with Mandard with a model proposed in oesophageal cancer[1]. Using an arbitrary scale to describe the balance between residual fibrosis and residual viable tumour, the authors categorised the degree of pathological tumour regression into 5 grades.
Source: Cancer Treatment Reviews - Category: Cancer & Oncology Authors: Tags: Controversy Source Type: research