Clinical Staging

Abstract

It is surprising that the accuracy of digital rectal examination has been formally tested only in a small number of studies. In 1976, Yorke-Mason proposed a clinical staging system which he hoped would allow a more selective approach to individual tumours. He had carefully compared the physical characteristics and histology reports on resection specimens with his own pre-operative clinical assessment by digital examination. The groups he suggested were as follows.

• 1. Clinical stage I (CSI): tumours such as benign rectal neoplasms with early invasion. These are freely mobile because the loose connective tissue space between the muscularis mucosae and the muscle coat of the rectum is not involved.

• 2. Clinical stage II (CSII): tumours in which invasion has extended across the submucosal plane into the true muscle layer. These are therefore less mobile than CSI but without being very firmly tethered. Yorke-Mason admitted that making this fine distinction was very much a matter of experience.

• 3. Clinical stage III (CSIII): where invasion extends through the full thickness of the rectal wall and out into the perirectal tissues there is a characteristic impression of “tethered mobility”.

• 4. Clinical stage IV (CSIV): when an adjacent structure is involved by local invasion the tumour feels fixed and immobile.